Saturday, June 28, 2008

Windy Day!

After the cold front passes through, northwesterly winds are on the increase with speeds approaching and potentially exceeding 40 mph this afternoon. A large portion of the state is under a wind advisory for this reason, as winds won't subside below advisory criteria until later tonight. As for high temperatures today, they'll likely range from near 70 in the north to the near 80 in the southeast. A few isolated showers/thunderstorms may occur this afternoon/evening across the northern third of the state as dynamics wrap around the low pressure system in MN/WI. A few of these storms may last into the nighttime hours over northeast Iowa; but otherwise mostly to partly cloudy skies across the state will lead to lows in the mid to upper 50s throughout.

A shower or two may linger in eastern Iowa on Sunday, but otherwise partly cloudy skies will yield highs in the mid to upper 70s across the state. Winds will still be gusty out of the northwest, ranging from 15-25 mph. Sunday night lows in the 50s throughout the state under clearing skies and subsiding winds.

We'll see highs on the increase for the first half of next week, reaching the lower to mid 80s by Wednesday ahead of the next potential storm system. Lows will also be on the rise, coming out of those 50s and be into the 60s throughout the state by Tuesday night as moisture also looks to increase. With warming and moistening air, that will likely mean an increase in the chance of thunderstorms over the state. It looks like the first chance will come up on Wednesday and Wednesday night, more details in later updates.

Friday, June 27, 2008

Severe Weather: June 27

9:30 PM Update: Thunderstorms have moved out of the state this evening, just a few trying to hold onto the state border near Dubuque. A few tornado warnings went out this evening, with only one report of a possible funnel cloud in Pottawattamie county. Otherwise large hail and very impressive winds will highlight the day for storms in Iowa, with the best video thus far coming out of the Omaha metro. Sadly, 2 fatalities and an injury have been reported in/near Council Bluffs when a tree fell onto a car with people within. Too many damage reports and stories, as well as videos, to even try and link to. You can check out all of the local TV stations, youtube, etc. for all of the vidoes and reports...

Although some thunderstorms are expected over the weekend and into early next week, the chances of severe weather look fairly marginal at this point.


5:05 PM Update: Continued development of the line of damaging winds continues, a new warning for this storm will include several counties in extreme southwest Iowa: Pottawattamie, Mills, Montgomery, Fremont, and Page. This storm is moving southeast at nearly 50 mph and will create winds of up to, or greater than, 80 mph! Latest reports have 50-60 mph winds with this line, but higher gusts are possible.

Outside of this line, additional development has taken place across portions of western Iowa, and over Worth county in northern Iowa. These storms are currently not severe, but have the potential to become severe within the next couple of hours. Other commitments will have me away from updating until later tonight, but like usual, please tune to local media for updates on severe weather.


4:50 PM Update: A potentially significant damaging wind event is unfolding with a line of storms that is near the Omaha metro area. The NWS office in Valley, NE measured a 77 mph gust before the equipment had a malfunction; later estimates which are being called 'conservative' had wind gusts of 80 mph. Other reports from nearby areas such as Elkhorn, NE also have had 80 mph estimated winds. This storm is likely to move into Pottawattamie and Mills counties in Iowa shortly... The storm is moving to the southeast at nearly 60 mph and has the potential to be damaging. It would be wise to take shelter much like this was a tornado warning, given the magnitude of the damaging winds.


4:10 PM Update: Thunderstorms have continued to develop across central Minnesota, with some development occurring in extreme northern Iowa (northern Kossuth county). Additional strengthening of storms has occurred across eastern Nebraska (northwest of Omaha) which has prompted a new severe thunderstorm watch that will include portions of southwestern Iowa until 10 PM. A line of showers, embedded thunderstorms, is working across northwestern Iowa currently as well with possible upscale development into more of a scattered thunderstorm event to the east of the Highway 4 corridor. At this time, no watch is in the process of being issued as storms have continued to struggle in this area due to larger-scale subsidence. Updates are possible later this evening if severe weather does unfold across portions of Iowa...


1:15 PM Update: The cold front, however diffuse and irrelevant it may be, is finally working into the state of Iowa this afternoon. Behind this front, an upper level wave, as well as a 500 mb wave, is working down out of Canada through the Dakotas. These upper and mid-level dynamic areas will be the focus for thunderstorm development this afternoon over the northern plains. Thunderstorms have begun to fire near/along the cold front and ahead of these dynamics over Minnesota; subsequently a severe thunderstorm watch has been issued for much of the state that is in effect until 8 PM.

Thunderstorms have attempted to fire along the IA/NE border, with the latest one being fairly healthy just to the south of Onawa, IA. Additional development is likely within the next couple of hours across the state of Iowa. The SPC has stated that a mesoscale discussion is likely to be issued 'soon', once this comes out, the watch issuance is also likely to come shortly thereafter. Expect the watch and/or discussion to come out by 3 PM, and likely include much of the state of Iowa. The threat today with lack of shear will be large hail and damaging winds, with it being a fairly isolated threat. More updates are possible this afternoon if watches/warnings begin to be issued.

Thursday, June 26, 2008

Severe Weather: June 26

4:30 PM Update: Warm frontal boundary looks to be situated from northern South Dakota near Aberdeen, SD extending southeastward through Pipestone, MN to Mason City, IA. To the east of that point, the front is barely recognizable given a heavy cloud shield in place over much of Iowa. As of 4 PM, only northwestern and/or extreme northern Iowa is under some type of clearing. Moisture return was limited by the convection this morning, thus only mid 60s are present. This is leading to the lack of instability over the state of Iowa, and eastern Nebraska/South Dakota for that matter. Only moderate instability currently present, but given more hours of sun we should see strong instability in place by 7 PM.

Current forecasts are still struggling with the morning convection, and placement of the warm front currently. The off-hour NAM has the best placement and parameters that are currently in place. Given current SPC thoughts as well with a discussion in place for western South Dakota; it seems likely that storms will develop in western SD/NE and track east/southeastward along and south of the warm front. These storms will track into eastern SD/NE by early nighttime hours with a continued threat of damaging winds and hail. The storms may enter into portions of MN/IA after midnight, with the potential for severe weather continuing. Other development may be able to form along and/or south of the front in eastern SD/NE and potentially extreme western MN/IA. However, this will take substantial increases in instability, and subsequent lift and other parameters; thus is very questionable at this time.


9:30 AM Update: Yesterday's severe weather threat panned out during the evening and into the overnight hours, with a multicellular line of storms that went through central Iowa. These storms were able to produce large hail and damaging winds over the state, along with fairly heavy rains.

Today we definitely did not have to wait as long for severe weather to come through the state, with a line of storms developing along the SD/NE borders and moving into northwest Iowa. Once again, storms developed in central Iowa as well, some being severe with marginal hail and damaging winds. The storms across central Iowa this morning did produce some hail in Ida county, but have since congealed into a substantial line of damaging winds. From Fort Dodge to Carroll between 8 and 9 AM this morning had several reports of tree and power pole damage, one measured gust was 76 mph in Coon Rapids, IA. This line continues to move east/southeast and is bearing down on the Des Moines metro currently with the continued threat of damaging winds.

Behind this line of storms, other thunderstorms have developed once again over portion of northwest Iowa and into southeast South Dakota. Other development in southeastern Nebraska in more isolated nature has occurred, a few of these cells are even severe warned currently.

The forecast is very complex for the day, but the current belief will be that this is only round 1 of severe weather for the day. Expect clearing to take place behind the several complexes of storms during the early afternoon hours. With return flow being strengthened, and clear skies allowing for warming temperatures, substantial instability should be back in place by late afternoon. With a stationary boundary draped over parts of the plains states, as well as several outflow boundaries from the morning convection, several may serve as development points for more thunderstorms by the evening hours. Developing storms this evening are likely to be supercellular in nature, capable of very large hail, damaging winds, and an isolated tornado is possible near any boundary. The best threat of a tornado with the boundary currently looks to occur through South Dakota and into northwestern Iowa, although other subtle boundaries may still produce tornadic storms outside of this area. Growth of the storms in the early nighttime hours is likely to congeal them into a line over central SD/NE, potentially southern ND. The line will be favored to continue to move east/southeast with time with the potential for a significant damaging wind event to take place over South Dakota, northern Nebraska, extreme southwest Minnesota, and into western Iowa. For this reason, the SPC has upgraded a large portion of the state into a moderate risk category for the combined potential of a significant wind event, and the very large hail potential with isolated development this afternoon/evening.

More updates are possible this afternoon with the evolution of the morning storms, and forecast adjustments. I will be around the northwest Iowa area today, ready for any development this afternoon as the potential is there for a significant severe weather day.

Wednesday, June 25, 2008

June 25 Severe Weather Threat

A weak frontal boundary is expected to drift southeastward this afternoon, and be roughly situated across central Minnesota into eastern South Dakota. This boundary, combined with other subtle boundaries from convection last night will provide several potential areas for development of thunderstorms this afternoon. Southerly surface winds will continue to push moisture into the state ahead of the slowly moving boundary. Dewpoints are expected to reach into the upper 60s, and lower 70s throughout. This moisture return combined with strong heating with highs expected in the upper 80s and even lower 90s will provide strong instability. This instability will lead to strong updrafts, and quickly developing storms this afternoon. Shear values are not expected to be sufficient for strong rotating storms, but supercells are still likely due to the amount of instability.

With thunderstorms developing along/near the surface boundaries this afternoon, expect storms to move off slowly to the southeast. With the strongest storms, the potential for very large hail (>2") is there, however, expect the main threats with the storms to be heavy rain, lightning, strong winds, and large hail. More updates are possible this afternoon if severe weather becomes likely, or if any drastic changes are made in the forecast. For now, be prepared for thunderstorms this afternoon, but also be ready for a beautiful day beforehand with highs in the upper 80s and mostly clear skies.

Tuesday, June 24, 2008

Multiple Severe Weather Days

The forecast has been fairly quiet as of late across the state, with little in the way of widespread severe weather. Thunderstorms and showers have managed to work their way across the state, with the occasional marginal hailstone and strong gust. This looks to change in the upcoming days, with the state included in several days of severe weather probabilities listed in SPC severe weather outlooks. Today's slight risk of severe weather does include portions of western and southern Iowa, however, the chances are still relatively low. Wednesday and Thursday feature the entire state under a slight risk once again, however, the actual probabilities listed are slightly elevated when compared to normal slight risk days. This indicates the potential for a more widespread, or potentially more significant, severe weather event across the state during the afternoon and overnight hours. Even in Friday's outlook, the state is once again highlighted for an area of potential severe weather as a cold front finally makes its' way into the state.

With the increased thunderstorm, and severe thunderstorm chances, this means that you'll likely feel an increase in both temperatures and moisture across the state. This will be true with highs in the 80s and 90s over the state throughout the rest of the week, with dewpoints rising into the 60s, and even lower 70s by mid-week. More detailed severe weather forecasts are likely to be posted the day of, with information on timing and what modes of severe weather seem possible. At this time, storm chasing doesn't look like a high priority, although storms that do develop into the area may end up yielding a storm chase if conditions do warrant. Chase status may also change if a potentially widespread or significant event comes into view in the upcoming days locally.

Saturday, June 21, 2008

Sports Photography

This past week has been fairly busy on the photography end, as I've recently begun a new part-time job working for a local newspaper, Lakes Pride. Four straight nights of traveling around to the local softball and baseball fields, gathering pictures to be used in the paper. Besides being used for the paper, all of the pictures have been uploaded to my gallery for parents, etc. to view and purchase if they wish.

For any people that are local to the area, the teams I have been covering include:

Armstrong-Ringsted, Estherville, Okoboji, Spirit Lake, Graettinger/Terril, and Harris-Lake Park. To view the latest galleries, please check out the Sports Gallery or view the front page of Jayson Prentice Photography for direct links to your sports team of interest.

Beyond sports photography, I'll be updating the Landscape section of the gallery with a few stormscapes, etc. from storm chasing this past spring. I am also still available for portraits throughout July and the first half of August, this includes family portraits, senior portraits, or any others that you may be interested in. For more information on any of my photography, please check out the website:

Jayson Prentice Photography

Friday, June 20, 2008

A Few Thunderstorms

The warm day yesterday had several clusters of thunderstorms during the afternoon and into the overnight hours. A severe thunderstorm watch was issued during the early afternoon for much of western Iowa. Although one tornado warning was issued in south-central Iowa during the mid-afternoon hours, the only reports received across the state of Iowa were larger hail and gusty winds. Luckily, the heaviest of the rains were over areas that are not currently flooding.

The same story is likely to happen once again today, with afternoon thunderstorms developing due to the warm air and some moisture return. The best chance for thunderstorms this time around should be for the northern third of the state, where a weak disturbance and potential boundary will aid in the development of those thunderstorms. Similar to yesterday, some of these storms will be capable of large hail and gusty winds, as well as frequent lightning.

Despite the thunderstorms, another great day outside with highs reaching into the lower and mid 80s throughout. Winds should be fairly weak and variable through the afternoon, with the occasional gust from any nearby storms that may develop. The chance of thunderstorms should expand throughout the state in the evening and overnight hours, however, severe potential does seem rather limited at this time. Overnight lows should range from the upper 50s to lower 60s from mainly north to south, with the slight chance of a very isolated thunderstorm lingering across the state.

For the weekend, a couple small chances of a thunderstorm or two, nothing widespread. Highs ranging from the upper 70s in the northeast to the mid 80s in the southwest for both Saturday and Sunday. Partly cloudy skies expected for both days, with a northerly wind between 5-15 mph. Lows overnight in the mid 50s to near 60 across the state, with light winds and mainly clear skies.

Wednesday, June 18, 2008

Featured in ISU News

An Iowa State Press Release today features your very own Iowa Chaser, Jayson Prentice. The article discusses Iowa State's Meteorology departments' involvement with the TWISTEX project, and includes quotes and information provided by several students that have been chasing with Tim Samaras and project TWISTEX.

Read the entire article: Iowa State News Service

Also notice, the featured image on the article is taken from the collection of images by Jayson Prentice. Just thought I'd share, as I just got the email stating that the article was released through ISU, and will also be released to local and regional news later today.

Isolated Thunderstorms... Warm Weather

Although the chance remains for isolated thunderstorms, nothing widespread or significantly severe is expected, thus the highlight for the week continues to be the warm and calm weather. Highs today can be expected to reach the upper 70s to lower 80s across the state, with lows tonight falling into the mid 50s to near 60 from east to west. A disturbance combined with adequate instability will allow for numerous thunderstorms to develop on the western plains. A few of these thunderstorms will make there way into the central plains, with more than a 50/50 shot of a thunderstorm along the Missouri River valley tonight. These storms are not expected to be severe, although some small hail and gusty winds may likely accompany storms overnight.

Isolated thunderstorm chances continue in the forecast for nearly the entire state on Thursday and Thursday night. Thursday highs should be in the upper 70s, and a few 80s, throughout the state. Lows overnight in the upper 50s and lower 60s.

The chance of a thunderstorm or two continues for the northeast portion of the state on Friday, but the chances diminish by the evening hours. Highs for the final day in the work week look to be near 80, to the mid 80s in the west. Lows to begin the weekend will remain fairly mild in the upper 50s and lower 60s.

Monday, June 16, 2008

A Quiet Week?

The upper levels are finally beginning to calm down, as a ridge begins to build over the Rockies and the high plains. This ridge in the upper levels will leave most of the plains in a fairly quiet period, with only occasional nighttime MCS thunderstorms expected. Areas of the high plains may see more frequent thunderstorms, although they will be highly isolated. Iowa should stay dry through Thursday, with thunderstorms possible with a weak shortwave moving through during the afternoon and overnight on Thursday. Even beyond Thursday night, it doesn't look like we'll see another good severe threat in the plains until early next week.

Today's forecast is for clear skies, northwesterly winds, and overall cooler temperatures for this time of year with highs in the mid 70s throughout much of the state. Tonight will see cool temperatures still, with little in the way of moisture present, lower to mid 50s expected. Tuesday highs expected in the mid 70s to upper 70s from northeast to southwest; lows overnight in the mid to upper 50s. As the ridge continues to build on Wednesday, highs will increase once again to the upper 70s to lower 80s from northeast to southwest. Moisture will be increasing as well, with southerly flow present, Wednesday night lows in the mid 50s to lower 60s from east to west.

A weak wave is likely to round the ridge and create enough upper level support for thunderstorms in Iowa on Thursday. During the afternoon, thunderstorm chances will be present for the western half of the state. Highs expected to range from the upper 70s to lower 80s from east to west. Overnight, lows will range from the upper 50s to lower 60s; chances of thunderstorms over much of the state, but the greatest over western and central thirds. To finish off the weak, a few thunderstorms are possible over the eastern third of the state during the day and into the overnight. Highs should range from near 80 to the mid 80s from east to west; lows in the lower to mid 60s throughout.

Enjoy the week's weather, it is a much deserved break from thunderstorms and severe weather that have been featured for the past week(s). More updates on the blog this week will adjust any of the forecast as necessary, and bring Thursdays' thunderstorm chances better into view. Also, look for pictures from both the June 11 and June 12 storm chases in Nebraska and Kansas.

Sunday, June 15, 2008

Fathers Day Forecast

Strong storms moved through portions of Iowa during the overnight hours, dropping large hail, damaging winds, and even a report of a tornado. These storms have since moved out of the state, however, another line of storms is ongoing across portions of southeast Iowa with the threat of large hail and damaging winds. Montgomery and Adams counties are currently under a severe thunderstorm warning due to the threat of quarter sized hail and damaging winds in excess of 60 mph. Expect these storms to continue to the east/southeast during the morning hours, a severe thunderstorm watch is in effect until 2 PM for portions of southern Iowa.

Additional thunderstorms are likely to develop this afternoon across the southern two-thirds of the state. These storms are likely to have the threat of severe weather, as even portions of the state are under a moderate risk today. The biggest risk with todays' storms will be damaging winds and large hail, however, a tornado or two may be possible with some of the storms, especially for southeast Iowa.

Highs for your Fathers' Day will range from the upper 70s to the mid 80s from north to southeast. Lows tonight from the mid 50s to near 60 from north to south as well. More updates are possible this afternoon, but please stay alert with local media for the threat of severe weather. This is especially true for those that are outside for the Fathers' Day celebration...

Saturday, June 14, 2008

Severe Weather - June 14

3:45 PM Update: Several thunderstorms have fired across the eastern half of Iowa, with several of them currently being severe warned. These thunderstorms are capable of large hail up to golf ball in diameter, and occasional wind gusts nearing 60 mph. These are also in areas that are already in extreme flooding, thus this is not helping the ongoing flood situation. For the latest radar updates, you can view the Iowa Chaser Homepage that is currently zoomed on the thunderstorm threat.

1:20 PM Update: A Severe Thunderstorm Watch has been issued for portions of central and eastern Iowa, extending into western Illinois. This watch will be in effect until 7 PM this evening, thunderstorms developing along and just ahead of a slow south-moving boundary should continue for the remainder of the afternoon. These storms are likely to be capable of large hail and/or damaging winds.

10:23 AM: Although the last storm system managed to take away much of the moisture that was present across Iowa, the warm temperatures and cool air aloft will once again allow for the development of thunderstorms over the state this afternoon through the overnight. Generally the thunderstorms may only produce heavy rains and lightning, still a bad thing for Iowa, there is the possibility of damaging winds and large hail with some of the storms that develop this afternoon and evening.

A weak wave of energy, combined with the remnants of a weak cold front will give way to storm initiation this afternoon. Although temperatures should be in the 80s throughout the state, and moisture is somewhat limited with dew points in the mid 50s to lower 60s; cooler air aloft should allow moderate instability to be in place this afternoon. This cooler air aloft will also allow for hail development and sustainability within the thunderstorms, thus the SPC has actually portioned a large part of the state under chances for significant hail (>2"). Damaging winds may also be a threat, as some storms may remain slightly elevated with the lacking surface moisture. At this time, the tornado threat appears quite low given the mainly elevated nature of storms. But, storms that can develop in the vicinity of another storm and realize locally enhanced moisture may be able to become surface based. This with any outflow or slight wind shift areas that the storm may encounter may allow for a brief possibility of storm rotation, however, currently this is believed to be a very 'what if' scenario.

These storms are expected to be isolated in nature, thus no widespread flooding is expected. However, much like the past week(s) any additional rainfall will likely initiate localized flooding. The state of Iowa is in the limelight due to a levee break in downtown Des Moines, along with the significant flooding of Iowa City and Cedar Rapids; other areas are as well seeing significant/major flooding of there areas which is hampering many throughout the entire state.

Friday, June 13, 2008

Traveling Home

On the road this morning out of Wichita, KS in-route to the soggy state of Iowa. I'm sure it has been covered extensively by all of the local and national media, so I don't feel the need to go through all of the areas that have been getting hit hard or all the details on who/where is evacuated. Several roads are closed throughout the state, thus the route on my way home is even effected between Ames and Terril. It may be a while before we can see the rivers truly drop to levels that aren't threatening to flood with every rainfall, even with some breaks in the storm systems.

The last two days of chasing have been frustrating to say the least with storm development being along a cold front, creating a line of storms. Wednesday storms were both linear or embedded within a line, not to mention movement to the northeast over 40 mph. We did manage one tornado out of this storm, essentially coming up on it as it formed just to our east. Otherwise some scary scud and outflow shelf formations on the storms, along with some amazing cloud-to-ground lightning.
Thursday was slightly better, even though we managed to miss the tornadoes in southern Kansas. The structure with the storms was amazing, with a great wall cloud and lightning with the first storm. Managed to capture 3 lightning strikes handheld during the day/evening; with additional strikes at night. Quite a few great panoramic images should come out of the storms yesterday, as the structure once they went outflow was impressive. One picture that I do hope turned out was an image of the striated storm just to the east of Wichita late last night. It was the best nighttime storm that I have ever personally seen, with constant thunder and lightning strikes. The storms were impressive nonetheless, it just seemed as if the storms struggled to produce beings they were in such a line fashion along the front.

On the next ~6 hours on the road I have I will likely begin to get pictures edited, see what I can manage for panoramics, and lightning. It looks like any chasing has came to an end for a while with ridging likely across the plains. Even with the ridging, it still looks like thunderstorms may be possible, however, nothing significant appears likely.

Thursday, June 12, 2008

June 12 Storm Chase

10:15 PM Update: It sounds like we'll finally be calling it a night, currently just about to turn northwest towards Wichita. Enjoyed the show just to the east of Wichita, beautiful striated storm that I believe I captured with some lightning illumination. Some other nice lightning strikes throughout the night, even now as we look towards our west/southwest as another storm has formed and is looking impressive. While sitting ~7 miles east of Rock, KS we did see several power flashes to our northwest, at this time its' unknown what damage was caused and what caused it. This will be our last day for this trip, looking to head home tomorrow...

8:20 PM Update: Hanging out between Emporia and Wichita, watching the continuous line have its' fun. The highlight of the day has likely been the light show, in which several people have gotten great shots from including Tony (already posted on his blog). We'll likely end up spending the night in Wichita, with a hopeful view of lightning to continue our fun. One thing that I will have to post is a lot of panoramics of shelfs, and a few general storm bases with wall clouds.

5:10 PM Update: Storms have fired and we are now on the chase with storms becoming severe warned already... Heading west out of Emporia.

4:45 PM Update: Sitting in Emporia, KS; awaiting the storms to finally root in and begin to become severe/tornadic. Currently watching a broken line, or line, taking shape just to the west of us... Getting everything going in the cars and then we'll be ready to head out and hopefully catch something a bit better than yesterday.


10:45 AM Update: Packing stuff up to leave from Lincoln, NE; believe we'll be taking roads down out of Nebraska City, NE and thus landing ourselves around Yates Center, KS by 3:30 PM. More updates are possible if we stop for lunch, otherwise once we arrive in the likely sunny Yates Center!


9:45 AM Update: Although initially on the trip it looked like this would be a one-day chase event, with the very small chance of a Tuesday storm when we went into southern South Dakota, it has turned into a little more. Today's forecast took a nice turn into being a little more active, especially for the threat of tornadoes today in southeastern Kansas. The entire group is ready for an actual supercell that is not embedded within some long line, and one that we can actually obtain data on. That is the goal for today, leaving Lincoln, NE sometime around 11 AM to head south into Kansas and begin one last day of chasing before a ridge sets in and the TWISTEX crew will likely be down for a while. More updates later as the forecast becomes more defined, as well as our route...

Wednesday, June 11, 2008

June 11 Storm Chase

12:45 AM Update: A very long day today, chased storms throughout southeast Nebraska. The entire line of storms were tornado warned, from southwest Minnesota to north-central Kansas. Ends up to be a very sad day today with a scout camp north of Little Sioux, IA that is all over the news. Also it sounds like several other areas, including metro areas, that took hits tonight. I missed all of the action in northwest Iowa today, but from the sounds of it, nobody could see anything with such heavy rain wrapping around these storms. Also with such a massive line moving northeast, it was nearly like watching the storm go by and awaiting the next... A full update tomorrow is possible, however, at this time I do know what the plan is for the day.


2:30 PM Update: Drove south for a ways along I29, have now found ourselves near Missouri Valley, IA. Have ate a nice dinner, but are still awaiting on something to become clear on which target (northwest Iowa or southeast Nebraska) will be better. At this point, it is still a wait to see which one will take shape, however, the the target of southern Nebraska and Iowa does look favorable at the moment.


11:00 AM Update: Just as an FYI, blog updates will be fairly sporadic beings I'll be with Tony. Don't want to have too many computers (3), GPS's (3), among everything else going on. So feel free to browse Tony's Blog as well for updates on my status. I will update when possible/needed.

10:30 AM Update: The group got together this morning at 9 AM to discuss target areas for the day. Fairly large, but disorganized, complex of storms is working through areas of western Iowa, southwestern Minnesota, and even as far south as northwestern Missouri. This complex looks to be well off of the boundary that is currently situated in central Nebraska. Behind this complex of storms and ahead of this boundary, moisture has already surged northward with fairly clear skies as well. As the storms continue eastward, similar things should happen to much of the Missouri River Valley; allowing for substantial moisture and instability to setup for the afternoon hours.

Current plan looks to have us heading south along I29 to get out of the cloud deck that just won't leave this morning. The forecast definitely does not look 'great', but given if things can fall together it could certainly be a productive day. No real target as of this moment, we'll likely head south within the next hour and reevaluate throughout the afternoon (early) before things start to take form.


12:00 AM Update: After treating today as a position day, certainly have to get something nice tomorrow although the forecast looks 'interesting' to say the least. Overnight convection, MCS's, may form both through eastern South Dakota into Minnesota and in extreme northern Kansas, eastern Nebraska into western Iowa. Currently, it looks as though both are having a hard time sustaining themselves into any type of severe mode. Cells that initially fired in northern Kansas are weakening, and the small development in vicinity of York, NE also cannot sustain itself at the moment. Although low level jet increasing would aid in their development, even if they do I feel that they would be well east of the Missouri River area by morning. This to me indicates that the latest model run by the NAM/WRF (00z) is not worth looking at too closely. They keep a large complex of storms around the Missouri valley through into the early afternoon tomorrow, much unlike anything that currently seems to be logical. With this complex hanging around the is supposed warm sector, it destroys any parameters that you would like to look at as far as surface goes...

The GFS thus is the favored at this point, although it still develops the MCS in eastern Nebraska, it moves it through central Iowa by early afternoon. This is a logical solution given storms speeds, etc. and thus is at least believable. This would leave a viable target area anywhere in the eastern third of Nebraska, moving into the western third of Iowa during the later afternoon, and evening hours. A lot of questions to still be answered come morning, but right now it looks like the day may be filled with excitement.

I will be the TWISTEX vehicle, with Tony Laubach, so beings both him and I are bloggers, be sure to check out his blog when I'm not available for updates while driving. Anything that he sees or reports, I will be right there to see the same things... Good night from Sioux City!

Tuesday, June 10, 2008

June 10 Storm Chase (Travel Day)

6:45 PM Update: Well after 'wasting' some time in Yankton, SD; it has been determined that today just isn't going to happen due to abysmal moisture return. The day is now a positioning day for tomorrow's potential outbreak of severe weather across portions of Nebraska and Iowa. Now in-route to Sioux City, IA where we will spend the night relaxing and looking at tomorrows forecast. An update may come later tonight pertaining to the forecast for Wednesday, but today appears to be about 99.9% over.

2:00 PM Update: I've caught my ride with the other ISU team members, Brandon Engelson and Mark Ketcham, and have continued towards our meeting point of Yankton, SD. Currently heading through Sioux City, with less than an hour and a half before meeting up and arranging vehicles once again. Today's forecast is still questionable, as moisture return thus far seems to be struggling with only mid 50s for much of Nebraska and southern South Dakota. Another update likely once we meet up in Yankton (~4 PM)...

9:15 AM Update: Although the day doesn't look great for tornadoes, the chances of a nice isolated supercell capable of large hail and some gusty winds is fairly high. A warm front will become situated across portions of southern South Dakota, and southwestern Minnesota over the afternoon hours. This front combined with a weak wave in the flow will allow for thunderstorm development along and to the north, mainly over areas of South Dakota, but as far east as the southwestern quarter of Minnesota and northwest Iowa in the later evening or overnight hours. The current chase plan is a target of Yankton, SD by mid-afternoon, then to re-adjust there during the afternoon as we await initiation.

Current RUC forecast from 12z paints a nice picture for a storm along the boundary in southern South Dakota. But, the caveat to this model picture is that moisture return via its' forecast may be substantially high (>5 degrees). This would cause a dramatic decrease in overall instability over the area, and an overall weakening of otherwise great potential. At this point, it seems like the moisture return will be the limiting factor today. Nonetheless, thunderstorm initiation is expected late this afternoon, or evening in southern South Dakota. Based on current 12z data that is in thus far, I'm leaning towards a target of Winner, SD!

Monday, June 9, 2008

Stormy Forecast & TWISTEX Operations

A lot of local meteorologists have been busy the past couple of weeks, with severe weather coming into the state in the form of large hail, damaging winds, and tornadoes. To add to the severe weather, all of the rain associated with the rounds of thunderstorms have created significant flooding concerns throughout Iowa and other surrounding states. Yesterday and today saw several rivers reach record depths, in some cases blowing away previous records by several feet. A lot of rural roads, and even some major highways, have been closed due to flood waters. Unfortunately, just as the rivers begin to subside another round of severe thunderstorms is on its' way over the state.

Even with only slight chances of rain in the forecast, we managed to have several thunderstorms cut across west-central Iowa this evening. They are now in more of a disorganized complex over central Iowa near the Des Moines metro and surrounding. These storms were able to become severe, with mainly a threat of marginally severe hail, although a few warnings for damaging winds have also been issued. These thunderstorms will likely maintain themselves for a while tonight, working into eastern Iowa within the next several hours.

Tomorrow has a warm front setting up to the north of the state once again, with southerly winds over the state returning moisture quickly throughout the afternoon. This strong moisture return, combined with ever-increasing temperatures, may allow for thunderstorm development once again. The best threat will be over northern Iowa, where they are situated near the warm front, however, a large portion of the state will see at least slight thunderstorm chances. The severe weather threat should once again be for large hail and damaging winds, as shear should stay further west along the front in South Dakota. A overnight complex of storms for Tuesday night isn't out of the question for a large part of the state, as they move out of South Dakota. Highs tomorrow should range from the upper 70s to mid 80s with dewpoints rising into the 60s under southerly winds. Overnight lows in the lower to upper 60s from north to south, and increased thunderstorm chances (especially northwest).

Wednesday sets the stage for the best threat of thunderstorms over the state, and the threat of severe weather (potentially significant) returns as well. A warm front should once again be positioned just to the north of the state in southern Minnesota. A low pressure center is forecasted to maintain in west-central Minnesota along/near the South Dakota border. To the south and southwest of this low, a trailing cold front should slowly move eastward during the day. Both the cold front and warm front should be sufficient to produce thunderstorms during the afternoon, with the potential for all modes of severe weather given shear and instability values of current forecasts. The best threat should once again occur over the eastern third of Nebraska, and the western half of Iowa, as well as nearby vicinities of extreme southeast South Dakota and southwestern Minnesota. More details on this threat in later updates, but definitely something for people to keep an eye and ear on once again. Highs on Wednesday near 80 in the north, to the mid 80s in the south; lows overnight ranging from near 60 in the northwest to near 70 in the southeast. As mentioned, thunderstorms likely during the afternoon over the western half; over the entire state during the overnight.

TWISTEX Update: I will be out chasing once again for this system with the TWISTEX crew, this time operating another vehicle (not the ISU car). Will be in southern South Dakota tomorrow for any potential thunderstorms that may be able to develop before the nighttime hours. An updated forecast for tomorrow's severe weather and TWISTEX operations will be made in the morning. Wednesday will be the main day of this operation, with a target possibly including a portion of western Iowa. Expect the next several updates to be focused on TWISTEX; although beings I'm actually driving a vehicle this time the updates may come less often. Look forward to more though!

Sunday, June 8, 2008

June 7 Chase Account

My chase partner for the day was my actual partner (girlfriend), Alyssa. Although she had been on two other chases with me, the second being this past Thursday, both of them have been busts. We are both happy to say that the third was not the same, as we combined to be on a total of 5 tornado warned storms throughout our journey of central Iowa. We began the journey after I picked up Alyssa from Wallingford, IA and we headed south and east, grabbed some late lunch in Emmetsburg, then awaited for some solid initiation of storms. Several updrafts were trying throughout the area to finally get rooted, and it seemed like the place to do so would be in vicinity of Algona. After the first storm to reach that area became surface based and broke through any inhibition it quickly went severe and tornado warned over Kossuth, Winnebego, and Hancock counties. We unfortunately let that one go and wouldn't catch up to that one...

Our true chase began with two small cells just to the east of Emmetsburg, and watching them we decided to head north towards Fenton. As we neared Fenton on the backside of this storm we saw a few lowerings, however, no significant rotation was noted at that time. Within 10 minutes the two smaller cells seemed to complete their merger and we ended up with the tornado warning. We continued east directly behind, and eventually just south of the rotation noted on radar. However, continued development to the south and west began to interfere with this storm. We finally ditched our first tornado-warned storm at Crystal Lake, at that point deciding to position ourselves right ahead of the new tornado warned storm to our southwest. This storm was much better on radar, and also visually as broad rotation throughout the lowering was noted. A few smaller lowerings within this broad meso were noted just to the north of Wesley, no tornadoes though. We continued on this storm as it neared both Clear Lake and Mason City, taking a route just north of those towns allowed a nice view of the now rotating wall cloud to the north of town. Reports did come in of a brief tornado north of Mason City, however, neither Alyssa or I saw this occur. We continued on this storm, alongside of the rotating wall cloud, a few brief funnels, and the occasional 'spin-up' of dust. Not certain if any of these dust whirls were associated with the rotation above, or if they were occurrences of an RFD, or even just wind gusts with the constantly 'lining-out' storms. Either way, it does sound like at least one of the 'dust-whirls' was reported as a tornado, and until proven otherwise it will count towards the tornado count (a non-condensed tornado). Alyssa doesn't really want to count it, beings it wasn't the classic tornado, but it'll count.

Upon leaving this storm, we then began to slide slowly west, although nearing Clear Lake another storm became tornado warned near the Mason City Airport. At the time we were just a mile east of the airport, looking straight at this supposed rotation that was indicated by radar. We finished off a loop back around and followed this storm to the east of Mason City as it also became outflow dominant. At that point, the only storms that continued to be tornado-warned were a ways south and west of us. With over an hour of daylight left, we dove south towards these cells and intercepted the first tornado-warned cell near Galt. This storm was already outflow, but was a neat sight with rain-bands moving through and blue sky in the background. Unfortunately, with heavy rain already upon us, no good pictures or video were taken of this site (similar to much of the day).

This pretty much ended the day, as we dropped further south our potentially sixth tornado-warned storm of the day had its' warning expire and not reissued. Thus, we end our count with five tornado-warned storms as mentioned above. We once again met up with the TWISTEX crew near a field of wind turbines and gather up a few images of the underside of the shelf and the turbines. A few images may be added tomorrow or later date once they are uploaded to my computer...

Total Mileage: 420 Miles (Overnight in Ames and Return Included)
Total Road-Time: 7 Hours, 30 Minutes (Additional 2 hours, 45 minutes on June 8)
Chase Sights: One Tornado; Multiple Funnels & Rotating Wall Clouds; Wind Gust ~60 mph

Friday, June 6, 2008

A Collection of 2008 Storm Chasing Images

Beings I've finally been getting some of my images online from the chasing that I've done over the past month, I thought I'd share. To view the complete collection of images, check out my 2008 Storm Chasing Gallery that I'll be adding to throughout the summer. All images below stretch from a May 22 to May 25 stretch that was spent on tornadic storms in the western half of Kansas.

Kansas Rope Tornado

Hoxie, KS Wedge Tornado

HP Supercell Panoramic

Quinter, KS First Tornado)

Central Kansas Wall Cloud

More Weekend Storms

Well if two straight days of thunderstorms isn't enough for portions of the state, there will only be a one day break before another round of severe storms hits Iowa. Last night saw another round of severe weather, mainly over the southern half of the state, and the most significant once again occurring over the southwest quarter where more tornadoes touched down. Early afternoon storms over portions of NE/SD and northwest Iowa brought the first warnings of the day, mainly for large hail and damaging winds; as well as flash flooding. These storms were just one ingredient that likely hampered additional development along the warm front in northern Iowa during the later evening hours. Storms that initially fired in Kansas worked northeastward and entered extreme southwest Iowa by the late evening hours with the threat of large hail, winds, and tornadoes. Just after 7 PM a tornado touched down just across the Iowa border to the east of Nebraska City, KS. As storms continued to move east/northeastward additional tornadoes were reported near Randolph, Cumberland, Creston, Monroe, and Kellogg. Other than tornadoes a few tornado reports near Ames & Boone (Nickel-Sized Hail), and several damaging winds with the relatively weaker thunderstorms. The damaging winds were likely a combination of not only thunderstorm strength, but the environmental wind fields were also very strong, leading to these high winds. Damage was even reported behind these thunderstorms with the strong environmental wind fields, measured gusts from Spencer were upwards of 58 mph; and a gust measured at my home near Terril reached 68 mph.

Temperatures today range from the mid 60s in northwest Iowa under mostly cloudy skies, to the mid 80s in the southeast under clear skies. Winds are still strong today from the southwest, 15-30 mph on average with higher gusts likely throughout the state. Highs today should be just a degree or two higher than current temperatures indicate. Lows overnight should range from the upper 50s to upper 60s from northwest to southeast; winds should begin to subside and switch to more of a southerly direction under partly cloudy skies. Weekend temperatures will have highs in the upper 70s to lower 90s on Saturday from northwest to south; highs on Sunday from northwest to southeast will range from the mid 70s to upper 80s. Lows overnight in the mid 50s to upper 60s for both Saturday and Sunday night. Thunderstorms likely during the day and night on Saturday, with additional thunderstorms throughout the day on Sunday and Sunday night. Severe weather chances for both days, the best chance on Saturday which is described in more detail below.

Saturday, June 7 Severe Weather Possibilities
A cold front will enter the state during the morning or early afternoon hours from the north/northwest and continue southward into the state. This front throughout the day will decelerate with time, potentially even becoming stationary across the state in the afternoon. Thunderstorms will more likely develop along this front in the afternoon, with strong instability in place with very warm temperatures and dewpoints pushing the 70-mark. The threat of these thunderstorms will likely pose for all threats of severe weather, however, the best chance for tornadoes does look to exist over the western half of the state during the late afternoon and evening hours. Large hail and damaging winds do look to be the greater threat, but discrete storms may pose the tornadic threat as mentioned. Timing will see thunderstorms initially develop over MN/WI and the northeastern quarter of the state during the mid-afternoon. Late-afternoon and evening expansion of thunderstorms over eastern Nebraska and western Iowa will then occur an hour or two later, with a potentially higher severe weather threat.

The SPC has the area under a slight risk, with probabilities of 30% and hatched indicating an enhanced severe threat over nearly the entire state. Later outlooks may upgrade this area to a moderate risk if conditions do warrant and updates to the blog will reflect that. Although the chase yesterday busted, depending on how the morning satellite and forecasts look, it may be worth another chase in Iowa tomorrow!

Thursday, June 5, 2008

June 5 Severe Threat & Chase

The 8 AM SPC severe weather outlook has upgraded a large portion of the plains to a high risk, with the upgrade coming on the heals of increased damaging wind potential. The setup is very unique for this time of year, as the features in the mid and upper-levels are more like an early spring severe weather outbreak. These features, combined with early summertime thermodynamics will make for a nasty outbreak for severe weather. The large question in place is due to the early spring-like features of the wind fields, with a lot of shear, but overall unidirectional wind fields in mid to upper levels will result in fast storm motions and a push for more linear storms. This is the reason behind the high risk upgrade, as it is felt that as storms evolve into a potentially bowing linear structure that a significant damaging wind event may occur.

Despite this feeling, the tornado threat with storms is still quite high, and wording still includes the potential for long-track and significant tornadoes. The surface features will become better defined as we reach the afternoon hours, currently it is believed that the surface warm front has already surged northward and has situated along a line from near Sioux City eastward to Davenport given latest surface analysis. The low pressure is currently in northwest Kansas, pressure falls have already begun across central Nebraska and will pull this low north/northeastward. A dryline/cold front will be pulled to the south of this low and will also serve as a focal point for storm development late this afternoon. Other storms may develop along the warm front, nearly stationary front, draped approximately along its' same location now.

Chase Forecast: I won't be traveling far from my home area, with the warm front featured dead-center across northwest Iowa I can't venture far away from that feature. Although storm motions aren't the most favorable, given the amazing shear values it is likely that storms will quickly rotate and potentially produce tornadoes. I believe development should occur along the warm front late this afternoon, along with additional development along the dryline in central Nebraska and southward. Storms in each area can become tornadic, parts of the region, especially northwest or northern Iowa may see more than one round of storms. Initial development along the warm front will eventually either move north or be overtaken by a broken line of storms moving off of the dryline in the nighttime hours. This second line will also have potential of significant damaging winds...

Will be watching how things evolve, may either vote to head slightly west from the Spencer location that I'm currently at... Or may not need to move anywhere if warm front can fire throughout.

Wednesday, June 4, 2008

June 4 Severe Weather

11:22 PM Update: The tornadic threat for Iowa is not completely over, however, the storm that has been a prolific tornado producer for several hours has finally looked to lose its' power. Although still severe warnings exist across the state, no tornado warnings exist at the moment. A few isolated severe storms do exist across the state, currently over Hardin, Sac, and Crawford counties. The previous tornado warned storm is still severe warned and covers Warren county. A bow echo line of storms is moving east capable of mainly damaging winds that is running from near Adair, IA to the south of Corning, IA... This may likely be the last update on tonights severe threat, as the thoughts now shift towards tomorrows' event which may be another day of tornadoes in Iowa.


10:30 PM Update: I have not been able to track the storms as they have went through the state, however, I feel that the post below definitely was warranted given the tornado reports that I've seen thus far. Several reports of tornadoes stretch along a line from Mills county eastward through Montgomery, Adams, Union, and now entering into portions of Clark, Madison, and Warren. This one cell has continued to move mainly eastward and has nearly continuously been a tornado producer. Other storms in the state are severe warned, this includes several counties in southwest Iowa as a bow echo is beginning to catch up to the tornadic supercell. Other isolated cells in west-central Iowa and north-central Iowa are also severe warned with the capability of producing large hail and damaging winds. Please stay tuned to local media or your weather radio as many are heading to bed...


5:45 PM Update: A new tornado watch has been issued for a large portion of Iowa, roughly the southern half of the state. This tornado watch has been issued based on a warm front that is situated across the state. Storms are likely to fire along this warm front as the evening progresses, the storms will be able to produce large hail, damaging winds, and isolated tornadoes. This tornado watch will remain in effect until midnight tonight...

Currently, a severe warned storm for large hail is within Adams county. While a stronger and tornadic storm has entered Mills county, the storm entering Mills county has strong rotation and has had a reported tornado previously. Other storms, including the storm already going in Adams county will have the potential to also become tornadic. Numerous other small cells do appear on Des Moines NWS radar, roughly along a line from Omaha to Bloomfield, IA. Anywhere along and north of this line may see severe or tornadic storms within the next several hours... Please watch your local news stations or listen to your weather radio for continued updates.

Chase Forecast: June 5

With the potential for a significant severe weather outbreak increasingly likely over parts of Iowa, specifically western Iowa, I will be on my way to the storms throughout the afternoon tomorrow. Latest SPC discussion indicates that there are some questions still to the evolution of the forecast, and in the storm evolution once they do fire tomorrow afternoon. Nonetheless, as the SPC also mentions, it does appear that a 'Significant/damaging event' will take place over the plains tomorrow.

Forecast models continue to have some struggles with the placement of surface features, most notably the warm front and low pressure positions. Last nights' consensus was to have the low placed in eastern South Dakota by 00z, with warm front extending eastward through South Dakota and into southern Minnesota/Wisconsin. This mornings' model runs took a slightly more west and south approach, leading to the extension of the moderate risk in the latest SPC day 2 westward. The 12z NAM indicated good timing on the 500mb jet and vorticity axis in correlation to 00z and the likelihood of storm initiation. The placement of the warm front was oriented from southwest to northeast, unlike previous model runs, and stretched from northeast Nebraska, along the IA/MN/SD intersection and then into southern Minnesota. The low pressure center at this time seemed to be much further south, in vicinity to the Norfolk, NE. This solution would still yield significant severe weather, it would however move the risk to mainly eastern Nebraska and western Iowa, and not include portions of SD/MN as much as previously thought.

The 12z GFS run is slightly east when compared the NAM in the 500mb jet and vorticity axis. This does not have a negative effect though, as the overall setup remains the same with good support throughout the levels for thunderstorm development in the late afternoon and evening hours. The surface setup with the GFS model run indicated less of a change when compared to last nights' runs. Low pressure still centered along the NE/SD borders in vicinity to Yankton, SD. Associated warm front extends east/northeast from the low over southeast South Dakota and into southern Minnesota. This is much more in line with current SPC forecasts and remains fairly consistent with previous models, thus is likely the favored model currently.

Ideal target area will be anywhere along a line from near Yankton, SD southward along the dryline throughout eastern Nebraska. This line is likely to include areas such as Norfolk, NE; Columbus, NE; Grand Island, NE; Hastings, NE; etc... My current chase plans include the morning at KICD Radio in Spencer, IA before departing in the early afternoon to head westward. Dependent on where the surface features are placed, continue west near the SD/IA border or drop south along highway 60 towards the Sioux City area. More updates are likely tonight and tomorrow regarding the severe weather threat both late tonight across Iowa, and the threat for tomorrow.

Severe Weather Outbreak

The state of Iowa is looking at three straight days of potentially significant severe weather. Today, or more likely, tonight will see a large complex of storms move into southwestern Iowa with the potential for both large hail and significant damaging winds. Storms today should fire across central Nebraska and Kansas, congealing into a MCS during the evening hours as it nears the Iowa and Nebraska borders. The extreme southwestern counties in the state may have a chance at an isolated tornado is storms can stay discrete for a longer period of time. The main threat with these storms should be damaging winds and large hail, with the best threat over southwest Iowa. The remainder of the state may still see thunderstorms during the overnight hours, with the potential for severe storms throughout. More updates on this threat may be posted during the evening or early overnight as the system is able to become better defined.

Tomorrow (Thursday) will see the northwest half of the state under the potential for significant severe weather, including very large hail, damaging winds, and tornadoes. A warm front to the north of the state, across southern Minnesota, with low pressure system in eastern South Dakota. A dryline and cold front will also be positioned from extreme eastern South Dakota through eastern Nebraska and then into central Kansas, Oklahoma, and even Texas. Although storms may be ongoing in the morning hours across portions of SD/NE/MN/IA, they are expected to clear off by the afternoon hours. Given clearing skies, strong instability should be present across the entire warm sector (south of warm front and east of dryline/cold front). The combination of strong instability and lift with associated fronts should allow storm development during the afternoon hours, with other storms developing further south along the dryline being more discrete due to a strong cap.

The storms expected across Iowa are likely to be supercellular, with very large hail and tornadoes being the main threats given strong shear at both low and mid-levels. Eventually the storms may congeal into another complex of storms, however this is not likely until they reach the eastern half of the state. Initial storms are being said to have the potential of long-lived, strong tornadoes. Thus, would definitely keep an eye and ear to the weather for tomorrow across parts of Iowa and adjacent areas.

Just a brief mention for Friday, as mainly a cold front passage over eastern Iowa will likely be capable of producing severe weather during the afternoon and evening hours. Although all modes of severe weather seem likely, the best threat will probably be large hail and especially damaging winds. More on this threat will be available as it nears...

Tuesday, June 3, 2008

Thunderstorms & More Thunderstorms

As you can tell by the title, those thunderstorms are not going to stop. During the overnight hours, a fairly weak wave of energy moved across the plains states allowing for thunderstorm development. As the storms continued to move across the state of Iowa, a bowing line of thunderstorms became evident across central Iowa. This bowing line of storms continue to move through the remainder of the the state, affecting mainly southeast Iowa during the morning hours as well. Reports throughout the night had mainly damaging winds involved with this line of storms, although a few hail reports were received near LeMars, IA and then again around the Des Moines metro, and its' surrounding. These storms have since moved out of the state, however, still posing a severe weather threat for parts of Illinois, and should continue to do so for the remainder of the day.

Back to the forecast, the risk for severe weather across the state of Iowa is nearly a guarantee for both Wednesday and Thursday. Currently both days are still highly variable when it comes to model consistency, so the area of most concern is hard to define even for tomorrow. Currently it is believed that a warm front will extend east/northeast from a low in northern Kansas. This warm front will set the stage for thunderstorm development during the afternoon hours, potentially closer to the low as a substantial capping may be in place over the remainder of the warm sector. With developing storms likely in central/eastern Nebraska, shear values remain substantial to warrant a belief of supercells capable of both very large hail and tornadoes. As the thunderstorms move into areas along the Missouri River and into Iowa during the evening and early overnight, cooling should take place at mid-levels to allow continued development and growth of thunderstorms. A large complex of storms (MCS) is likely to travel across the state, capable of large hail and damaging winds. Currently, the best threat for this MCS should be over the southern half of the state, however, given current model inconsistencies this area is not well guaranteed. Later SPC outlooks within an hour, as well as tomorrows' early outlooks should be able to have a better handle on this storm system and I will update accordingly.

Thursday's setup looks even more favorable for significant severe weather across much of the state of Iowa, and other areas in the plains. The low pressure system should be situated in eastern South Dakota at the surface, with associated warm front across central Minnesota. A cold front and dryline will be located south of the low, draped across extreme eastern South Dakota and Nebraska, as well as central Kansas, Oklahoma, and even northern Texas. Substantial capping may be present to the areas south of I80, making thunderstorm development questionable through the evening hours. North of there however, expect significant instability and lift to allow thunderstorm development along and just ahead of the cold front and dryline. These thunderstorms are forecasted to have significant moisture and lift, combined with moderate to strong shear values. Indicating that supercells capable of very large hail, damaging winds, and tornadoes are likely. This threat covers a vast majority of the state at this time, later outlooks and forecasts should be able to better define an area of enhanced severe weather with upgrades in risk category via the SPC are likely. Once again, updates on this situation will be posted as warranted...

Monday, June 2, 2008

June 2 Severe Weather

Showers and a few embedded thunderstorms are currently working into western Iowa this morning in response to overnight convection in Nebraska. Other storms, some severe, are also moving southeastward from Nebraska into parts of northern Kansas at this time as well. Behind both of these clusters of showers/storms, it is expected to clear off over western and central Nebraska/Kansas. With a lesser extent of clearing currently expected over eastern Nebraska and over Iowa/Missouri. Where the sun can shine, moisture and heating should combine to allow sufficient instability for severe weather later this afternoon. The combination of this instability, and the sufficient shear values will allow for discrete storms capable of large hail, damaging winds, and isolated tornadoes. The best threat currently looks to include a majority of Nebraska, northern Kansas, and potentially far northwestern Missouri.

For the state of Iowa, expect the showers and embedded thunderstorms to continue to slowly move across the state this morning. Leaving behind a fairly stringent cloud deck that will limit daytime heating over much of the state. The lack of heating will only allow for some elevated instability to occur this afternoon, thus do not expect additional thunderstorm development this afternoon. With the primary warm front situation over southern Nebraska, southeastward into portions of Kansas and Missouri, expect thunderstorm development north of the front this evening in Nebraska to work east/southeast into portions of Iowa. These storms tonight may be capable of damaging winds and marginally severe hail, however, given the lack of instability with currently cloud cover lingering for a majority of the day, the severe threat will be fairly limited.

Other updates may be posted later this afternoon if clearing can occur, leaving an increased potential for severe weather across the state.

Sunday, June 1, 2008

Severe Weather Threat

Another storm system moving into the plains will put the state under another risk of severe weather tomorrow, June 2. As mid-level winds become westerly in nature, indicating more zonal flow; low-level winds will be backed to the southeast and even east during the afternoon hours. This shift in winds with height will allow for sufficient shear values throughout portions of NE/KS/IA/MO for supercells. Low-level shear becoming enhanced with the easterly surface winds over portions of Nebraska, Iowa, and potentially other areas, for a tornado threat during the evening hours.

At the surface, a warm front will likely be positioned across extreme southern South Dakota and Minnesota, and also over portions of central/western Nebraska. To the south of this feature, expect mainly clear skies for the afternoon hours will provide sufficient instability for severe weather as well. Thunderstorms are likely to initiated over Nebraska and South Dakota during the late afternoon hours, moving into areas of Iowa and Missouri during the evening and overnight. The initial storms are likely be remain fairly discrete, with the potential for all modes of severe weather. With time the storms should congeal into a potentially significant MCS capable of damaging winds and hail, with a brief tornado still remaining possible.

More details on the position of the warm front, how well the area south of the front can clear, and what the trigger for convection to begin will become clear during the day tomorrow. It is expected that the SPC will upgrade the risk area to a moderate, for at least the area that is forecasted to receive the significant MCS during the evening and early nighttime hours. Another update can be expected late tonight or early tomorrow with more details on the locals expecting the more significant severe weather.