Saturday, May 31, 2008

A Short Break

The severe risk of the 29th wasn't nearly as bad as it could have been over the state of Iowa. Although several tornado reports were received during the early nighttime hours, thankfully the storms did not have a lot of energy to work with. No injuries or fatalities were reported with these tornadoes that occurred mainly in the southern two-thirds of the state. Damage surveys were completed for tornadoes that occurred over Clarke, Warren, Lucas, Marion, Mahaska, and Dallas Counties yesterday (May 30), they can be found here. Other reports of tornadoes over parts of central Iowa were received late Thursday night while a line of storms were making their way across the state. No surveys have been completed for these storms, although some damage was reported with these tornadoes or straight-line wind events.

Currently the only threats that we have over the state are some of the flooding that is occurring and did occur. Yesterday saw major flooding occurring across portions of Ames, IA near campus of Iowa State and over other areas of town. Moderate flooding is continuing today in vicinity to Marshalltown, Des Moines, Colfax, and Van Meter. Minor flooding is also occurring across a large portion of the rivers in central and southern Iowa. This flooding should subside as warm temperatures and clear skies allow for plenty of evaporation.

The clear skies and warm temperature are much improved for the forecast instead of cloudy skies or severe thunderstorms. Of course, most people who follow the weather during the months of June in Iowa it is only a matter of time before the warm temps and clear skies give way to stormy weather once again. Some small thunderstorm chances are in the forecast for the weekend, however our next big storm system looks to come in for Monday which may bring in the chance for severe weather once again. Looking even further ahead in the forecast brings in mild temperatures, mainly 70s and 80s, with another strong storm system coming into the forecast for the Thursday time frame.

Temperatures today will range from the upper 70s to mid 80s across the state, slight chances of thunderstorms through in the evening and early overnight. The best chance for these thunderstorms will be over the northeast quarter of the state, an isolated severe storm is also not be ruled out at this point. Lows tonight in the mid 50s to lower 60s from north to south across the state, with once again the slight chance of a thunderstorm over mainly northeast Iowa. Sunday's highs in the lower and mid 80s throughout the state as winds shift from northerly to more westerly (10-20 mph); Another great weekend day as we enter the month of June. Overnight lows on Sunday will range from the upper 50s to lower 60s, increasing moisture as winds begin to shift southward will also yield to slight thunderstorms chances for western Iowa overnight.

The southerly winds, increasing moisture, and the movement of another storm system towards the plains states will give way to another chance of severe weather over the state on Monday and Tuesday. Although both chances will become better defined in the coming days, it appears that all modes of severe weather (hail, wind, and tornadoes) may be possible. More details on these severe threats as the events become better defined...

I'm currently also going through the hundreds of photos from the chase trip last week and early this week. I hope to have a majority of those online tomorrow morning sometime and will likely make a special post to reflect those additions.

Thursday, May 29, 2008

May 29: HIGH RISK in Iowa/Nebraska

6:25 PM Update: Several clusters of thunderstorms are currently affecting portions of southeast South Dakota, eastern Nebraska, and central Kansas. A line from approximately Kearney, NE to Grand Island, NE is currently being affected by a line of storms that are capable of producing tornadoes. These storms have had a history of producing tornadoes and may continue to do so as the night progresses. Additional thunderstorms are expected across eastern Nebraska, and western Iowa as we enter the nighttime hours. Currently, it is believe that the severe threat will continue late into the night, as the storms have the capability of tornadoes, large hail, and especially damaging winds. More updates are possible as storms begin to enter the state...


The SPC has put areas of western Iowa under a high risk of severe weather for this afternoon, evening and even overnight. Other large portions of the state are under a moderate or slight risk for severe weather as well. Today's setup includes a warm front that is likely to be draped near the Missouri River Valley, a dryline across central Nebraska and a low pressure system in northern Nebraska or southern South Dakota. The combination of these surface features, along with warm temperatures and high dew points within the warm sector will combine to produce strong supercell thunderstorms. With wind fields being favorable for both low level shear and overall storm relative shear values, the risk of tornadoes is high. Storms should develop late this afternoon along the dryline in central Nebraska, with additional development possible along the warm front or other convective boundaries in the warm sector likely in the late afternoon.

Storms should move mainly east or northeast, typically between 20-35 mph. These storms should be able to remain discrete throughout the afternoon, evening and early nighttime hours. While remaining discrete, the risk of very large hail, damaging winds, and potentially strong tornadoes will exist across eastern Nebraska and northwestern Iowa. Overnight, storms will congeal into a large MCS, capable of producing strong damaging winds, large hail and the potential for tornadoes. This MCS will evolve over much of the state of Iowa during the overnight hours with these risks of severe weather.

This is a very dangerous situation that has been indicated by the forecasts, and by forecasts throughout the national weather service. People are going to be urged to pay very close attention to the weather as it may rapidly change and become increasingly dangerous. I will likely be out chasing in northwest Iowa, relaying reports to local officials if severe weather does occur. Hopefully we will have a safe day of severe weather across the area...

Tuesday, May 27, 2008

May 21-27 Chase & Travel

Today finds the severe weather threat for the plains diminishing, with only minimal chances for severe weather and nearly no chance of significant severe weather. For this reason I am back on the road to Iowa (490 miles), currently traveling I70 near Salina, KS with under 6 hours of driving remaining. I will be going through plenty of video and pictures over the next few days from this past trip, all-in-all I believe I have 8 tornadoes, wind gusts over 100 mph, and 2"+ hail to show for the trip. It is by far the best chase I have been on and certainly glad that I was a part of the TWISTEX group for this event.

Other happenings on Sunday, including the Iowa tornado that went through Parkersburg and New Hartford areas are disappointed in the stand point that it was a deadly severe weather outbreak this past week. I have not even had time to look back at all of the events that took place even in Kansas, but I do know that people were killed in western kansas on Thursday and/or Friday. If you read through the information on the TWISTEX site and what we are doing, I'm certainly glad to be aiding in scientific research on storms, etc...

My previously scheduled time with TWISTEX has came to an end, and others are going to take in place my role that I had this past week. I will still continue to chase this season, likely throughout the northern plains outbreaks and local chases in my northwest Iowa region. Maybe I will meet up with the TWISTEX crew somewhere in the northern plains and enjoy conservations like I have this week. It was a great week with the storms and the people, so just to put out a nice thanks to Tim Samaras, Carl Young, Dr. Bruce Lee and Dr. Cathy Finley, Tony Laubach, Verne Carlson and his sons, and my fellow car-driver Chris Karstens. Enjoyed meeting several of the other chasers out there this past week, glad that I have not heard of any significant injuries to those that were out there during that crazy two day stretch.

Next chance of good severe weather looks to come on Thursday, with the theat even beting in the northern plains states of SD/NE/MN/IA! More updates on this threat in upcoming day(s).

Monday, May 26, 2008

May 26 Chase

9:00 PM Update: Now filling up with gas in Stafford, KS and on our way back to Great Bend, KS where we began the day. Intercepted the storm to the east of Pratt, KS as it was tornado warned, however, not too much was observed with the storm going outflow dominant within a half hour of our arrival. Should get to Great Bend before 10 PM and get some supper there...

7:05 PM Update: The chase is already over for the day, dropping south from Great Bend ahead of a clump of thunderstorms until finally coming upon the tornadic warned storm near Greensburg, KS. The storm looked good at times, however once that occurred then the cell had to ingest another cell that was coming up from the south. After three or four cell mergers, the storm had finally had enough and went mainly outflow dominant. In the process of the chase, all four of the vehicles managed to run into golf ball sized and larger (2"+) hail. This managed to put cracks into 3 of the 4 vehicles windshields and dented all four. We'll review the HD video we had running in our dash to hopefully get a few vid-grabs of the hail. In the meantime, headed back to Great Bend, KS to spend the night and in-route to bust through a large line of... Actually now in-bound towards a tornado warned cell that also has tornado reported, so the chase is not quite over!

2:55 PM Update: Been watching the outflow for the past hour plus, it looks to have stalled out on a line from near Medford, OK through Great Bend, KS. Warm front just to the north, dryline well off to the west at this point which is only a small concern at this point. Current tornado watch has us fairly well centered in the middle of it currently...

1:25 PM Update: Sitting just outside of Larned, KS after eating at a local Pizza Hut in town. Now watching Tony Laubach taking some pictures of the local wildlife, cows and goats. After the morning discussion we were aiming more towards the KS/OK border, however now with the warm front positioned well north of the previous forecasts we are going to hold here. Outflow boundary to our east, moving west, may come into play later on this afternoon. Instability is amazing given the very warm and moist air that is present, hopefully the shear can also be realized with some backing winds. Some flat cumulus starting to develop, but feel that another hour or two should start to see the storms develop.

Sunday, May 25, 2008

May 25 Chase

8:10 PM Update: Heading back to Great Bend after today's chase, intercepted several tornadic cells although only one or two showed promise. Came away with several nice images of a rotating meso that was very low to the ground, and also of a nice shelf as the storms continued to gust out. As we sat well south of Rush Center, KS during the past hour we saw several outflow gusts that picked up dust from fields/roadways. Came away with some nice images of that event as well. Not as good as Thursday/Friday, but it wasn't expected to be and overall I didn't think it was a terrible chase. I am sad to hear that instead of the lining crap that we had here, northeastern Iowa got to see a nice supercell that unfortunately may have caused some significant damage.


6:40 PM Update: Sitting south of Rush Center, KS on the edge of this lining out crap of a line here in Kansas. Doesn't look like much is going to happen here, but not quite over yet. Final update when we are on our way to the hotel later...


1:00 PM Update: Tornado watch already issued for portions of western/central Kansas and already a few cells and good cumulus cloud fields showing up on radar and visible satellite respectively. We are currently still westward on I70 and look to remain so for the time being. TWISTEX blog was updated with the latest from Tim, today looks to hold some nice hope and tomorrow even better.


8:00 AM Update: Already up, hopefully with others in the group doing the same, and getting ready to depart for a target in northwestern Kansas. The morning SPC update solidified are concerns about the area, as they introduced a moderate risk with 10% tornado risk, hatched as well for the threat of a potentially significant tornado once again. Sadly this doesn't look to venture too far from Thursday & Friday's storm paths that went through that same area. It isn't going to be the greatest of areas to chase, with the knowledge that all unpaved roads are not in the best of condition. I'm pretty sure that by the time this trip is done, I may very well know northwestern Kansas as good as my home area in northwestern Iowa!

The forecast does look promising, as a strong surface low develops and deepens during the afternoon hours in eastern Colorado. This will provide winds from the southeast over parts of western/central Kansas. These southeasterly winds will provide the area with enhanced low level shear to combine with substantial instability. A pseudo-warm front may be draped across northern Kansas, with dryline across western KS southward into the OK/TX panhandles. The best tornado play will be where the winds locally become southeasterly in response to the low, moisture pooling may also occur in the potential trip point region in western Kansas as well. Does not look to be a bad chase day in western Kansas though at this point.


1:15 AM Update: After a one-day bust, hopes are not all that bad as at least two more days of chasing is in store for us in Kansas. More information on how tomorrow will play out and our plans will surface tomorrow morning, but currently it looks to be an early departure from Lincoln, NE in order to make a western Kansas target.

Saturday, May 24, 2008

May 24 Chase

8:15 PM Update: We moved slightly east mid-afternoon to the south of Aurora, NE to await the dryline that never came. The dryline ended up actually retreating to the west to the south of Grand Island or the I80 corridor and even north where the dryline was still moving east the storms struggled. Although several chasers/spotters reported a wall cloud or funnel, these reports came without warnings from the NWS so the validity of any rotation is suspect at this point. Maybe some more posts tonight once we look over some things from days past, and ahead for the next couple of days potential. Overall, today couldn't be as good as the past two and most chasers busted unless you were somehow lucky enough to be in northern Oklahoma.


3:45 PM Update: Still awaiting some good signs of convection, some small cells to our northwest that may be able to do something. At this time however, they don't look like much. Still working on issues with the mesonets, etc., will hopefully be ready to go shortly as tornado watch has already been issued for the area.


3:00 PM Update: Currently just to the south of Grand Island, awaiting the dryline to develop here in central/eastern Nebraska. Managing some minor repairs still, but doesn't look to be too much longer before we start to see something on the day. Definitely does not look to be as good as the past two, but hopes still good that we'll see something today! Overall the reasoning behind not as high tornado hopes includes the fact that overall shear is not as good, with more southerly flow at the surface to go along with southwesterly flow aloft. Instability (moisture) not as good either, but still sufficient.


12:00 PM Update: Currently on the roads of Kansas, just south of Nebraska and our target area for the day in southeast Nebraska. Today doesn't seem nearly as good as the previous two, but the entire group is still confident that tornadic supercells will not be lacking today. Today may actually turn out slightly better to the fact that we won't have continual development and a training of tornadic supercells. Or this could also be a bad thing as if we lose the one tornadic storm, then there is nothing else to fall back on. Either way, today looks to be another solid day of chasing for many who have taken off this holiday weekend to get their storm chasing 'vacation'. Currently the best forecast will have a cold front over SD/NE with a dryline as well over parts of southern NE/KS/OK/TX. Surface winds from the southeast should favor convergence along these fronts with winds to the southwest or west. Instability should not be lacking, even though dewpoints are not nearly as high as yesterday in Kansas. Should not be quite as exciting or early as yesterday's beginning, so I should have another update later this afternoon.

Friday, May 23, 2008

May 23 Chase

Several Updates will be posted within this post, the posts will be in chronological order with the most recent update being first. The time of the posts will be shown in bold for ease of use (All times are CDT).

12:45 AM Update: Another late update after another amazing day, at least 3 tornadoes (likely more) around the town of Quinter, KS. We began with a nice cone to the south and west of Quinter, which included a satellite tornado. We then captured at least two more tornadoes north of Quinter which included some intense moments with a strong RFD gust that came around and wrap around this tornado. Once this occurred, we were left with a large tornado in front of us in which was at least a mile wide if not greater. Once we managed to get out of that situation, we ended up not having any great road options to other storms to the south and were left with only some nice views of potential RFD's, etc... I'm sure there is plenty of video/pictures of all of those tornadoes that we captured as well. Today's chase facts included a total of 9 hours, 10 minutes of chasing and 269 total miles. Tornado count for the two-day adventure thus far is 7, potentially up to 9 after video review. More to go as at least two more days of chasing is left to go.


3:15 PM Update: First tornado warning of the day to the south of Gove, KS once again. We are just north and getting ready to turn south to intercept the storm, very large hail is going to be a concern today. But, the bigger concern will undoubtedly be the tornadoes that are likely throughout the I70 corridor. Updates are not likely until we reach the end of the day now...


12:15 PM Update: Just fueling up in Hays, KS and getting ready to depart and head northwest on I70 back fairly close to where we began the day yesterday. Today once again looks like a high quality chase day, with a dryline draped across western Kansas and a warm front across Kansas from northwest to southeast. The best threat of tornadoes looks to extend across Kansas, specifically northwest and north-central; then also over parts of western Nebraska. Spent the morning getting the car cleaned out after an adventure in mud, rain, etc... (Another story that I didn't mention last night). As for yesterday, if you are interested in some greater detail of what myself and a few others saw you can check out Chris Karstens Blog. That'll be it for this update, time to check out some maps for today and pick out a nice target, and also find some food.

Thursday, May 22, 2008

May 22 Chase

Several Updates will be posted within this post, the posts will be in chronological order with the most recent update being first. The time of the posts will be shown in bold for ease of use (All times are CDT).

12:45 AM Update: Spending the night in Hays, KS after a tremendous day of chasing throughout north-central Kansas. The day totaled ~8 hours of chasing fun while covering just over 300 miles (307 to be exact). We had kind of a late start out of Goodland today, but that turned out alright as we bagged at least 4 tornadoes around the Hoxie, KS area. One of the four included the multi-vortex that was near Hozie and was quite tremendous in its' circulation; ended up within a mile of that as it crossed highway 24. To the northeast of Hoxie along highway 23 also held some fun as we had two ground circulations develop within 100 yards of the mesonets. A solid day with a lot more stories then I have to offer tonight, all the more exciting as we still have at least 3 more days of chasing to go!

3:05 PM Update: Finally got outside of Goodland, KS after getting all of our mesonet problems and logistics out of the way. As we left we got a dose of some pea to just above dime sized hail and the storm went severe warned. Now headed east on I70 and then will likely dive south or await the arrival of a line of storms, which now include a tornado warned storm. Very windy, 35-45 knots on average, with plenty of tumbleweeds to catch in grills like Verne Carlson already has. The fun is about to begin with storm motions 40-50 mph and plenty of them. As stated, Verne Carlson is with the crew and actually has his live streaming online, check it out here.


9:00 AM Update: With several hours of waiting on our hands, we are stuck looking at everything you can look at as far as model runs and mesoanalysis go. Samaras, Laubach, Carlson, and others should have to depart Denver by 11 AM CDT or within 2 hour to make it to Goodland, KS by 2 PM CDT as planned. Model forecasts from last night and this morning are liking a surging dryline, but I'm not sure if I want to believe whole-heartedly in that decision. The warm front is also shown to not be nearly as far north as previous forecasts, and although it should surge northward it has a question in how far north it may make it. I believe that we'll drop south from Goodland, maybe a bit east if the dryline does look like it will make that surge. Storm motion are expected to be nearly north, ranging from 30-40 knots, but any strong right-mover should be able to go northeast or maybe easterly at a pace of only 20 kts (I hope). I may throw in another update this morning once I hear word from Tim, otherwise look for the next update to come early/mid afternoon as we make our adjustments.


8:00 AM Update Awoke to the sounds of constructions workers leaving the Super 8 here in Goodland, although I'm sure there are plenty of chasers around as well in town. The rumor that Colby, KS was chalked full of chasers was true, the Discovery/TIV/DOW circus group was staying at the Super 8 over there. Plenty of chasers out today and likely the remainder of the weekend as this is shaping up to be one of the better outbreaks of the year, with the addition of it being in extremely chaseable territory. Thus far the plan for today will include sitting back and relaxing here in Goodland until ~2 PM CDT when the remainder of the group will hopefully arrive. After that, we'll head off to our best target area which will likely come a bit south, maybe east, from where we are now in Goodland.

Wednesday, May 21, 2008

May 21 Travel Day

Several Updates will be posted within this post, the posts will be in chronological order with the most recent update being first. The time of the posts will be shown in bold for ease of use (All times are CDT).

8:15 PM Update: We have arrived in Goodland, KS at the Super 8 which features only 2 more rooms left (both smoking). Lady at the front desk shared that Colby, KS hotel rooms were booked with various chasers so it was wise that we kept moving west and arrived here. Several severe thunderstorms just 50 more miles to the west, however no need to drive another hour to get to them and another hour back to a hotel room so we've stopped here and will likely spend the rest of the night looking at tomorrow's prospects and watching some television. This will likely be the last update until tomorrow morning when the May 22 chase post can get underway. Here are the details thus far from the trip:

May 20/21 Miles: 711
May 20/21 Time: 11 Hrs, 10 min


5:15 PM Update: Although some thunderstorm activity has initiated along the dryline, we don't feel like a chase taking us further north is worth our time. With tomorrow's target likely be in northwestern Kansas, we've hopped off of I80 and are zigging and zagging down to McCook, NE where we will then likely continue into Kansas. Although this is likely to be a fairly long drive, this should set us up for nearly no driving for tomorrows' target. Both Tony Laubach and Verne Carlson have headed out today and are around the northeastern Colorado storms. We will be keeping an eye on storms as they continue to develop along the dryline, maybe a good show can be along our route?! Next update likely to come once we've reached our destination for the night.


12:50 PM Update: On the road, getting all settled into our Cobalt, and enjoying the 200-some XM Satellite radio stations. The SPC expanded todays' risk in the far western regions with an increased hail threat as well. We should reach Ogallala, NE before 6 PM MDT and thus have time to view any storms that are in extreme southwest Nebraska and vicinity. The day 2 outlook from the SPC upgraded to moderate risk and had some nice wording in place, thus tomorrow looks like a great day for chasing in Kansas! Next update will likely be when we reach Ogallala, NE.


8:15 AM Update: The ISU crew (Chris Karstens & Jayson Prentice) will depart today from Ames, IA and begin our journey out west for a several day event of severe weather. TWISTEX doesn't look to become operational until Thursday, with others arriving in Denver this evening. The ISU crew will treat this as a travel day, and a potential chase day if storms can fire along I80 in southwestern Nebraska or in extreme northeastern Colorado. Previous departure was expected to be around the current time, however with the severe threat being limited the departure from Ames has been moved back to ~Noon today. We may just leave slightly earlier than that, as the SPC has expanded the slight risk and latest RUC forecasts have some favorable parameters within our target area of traveling.

Tuesday, May 20, 2008

Chase Forecast: May 21/22

TWISTEX will become active tomorrow as all involved prepare for several days of active severe weather in the western plains. Chris Karstens and I will depart Ames early tomorrow morning and hit I80 to the west through Nebraska, hopefully arriving mid-afternoon. Although Wednesday does hold some potential for severe weather, mainly for large hail, the day will mainly be a travel day unless something drastic can occur with the forecast. Nonetheless, the option will be there to go after a storm that may be able to form along the high plains of NE/CO, maybe Wyoming?

Wednesday should feature a deepening low over northeastern Colorado, which in response will allow for strong moisture return into the high plains. The corresponding moisture return will lead towards a very narrow axis of a warm sector just east and north of the low. Currently the SPC outlooks indicate the best chance being north and northeast of the low, with lesser concern on areas just east of the low. Further south along a trough, or pseudo-dryline the capping will be of major concern with very warm 700 temperatures and thus no risk has been outlined. The tornado threat is likely minimal with the lack of shear and overall instability that will be featured, thus a large hail threat is the main concern for this forecast. Likely to have multiple clusters of thunderstorms to the north of the low over the Nebraska panhandle and southeastern Wyoming where surface based CAPE values between 500-1500 J/kg will yield storms capable of producing large hail. Further south to the east and southeast of the low, while moisture and overall instability should not be a problem; 700mb temperatures of 11-15C will likely hamper development. This area may be an area to watch though, as if a storm can breach the capping inversion it does seem that conditions are favorable for severe storms as well. Beings the terrain of southeastern Wyoming is not that favorable, plus the idea that the threat on Thursday will also be near the NE/KS borders it does look like we'll play along the NE/CO/KS corners and hope for that rogue storm.

Thursday is coming together for a significant severe weather event along the high plains. Continued low pressure system in northeastern Colorado will continue to be in place, with the aid of a strong warm front and dryline will focus the severe weather threat.

Strong moisture return as indicated by the green arrows will continue throughout the day on Thursday, providing mid 60s dewpoints throughout the warm sector. Upper level support with good vorticity advection and strong divergence should be located across western Kansas and Nebraska. The best low level and overall shear does however seem to be limited the further south you go, indicated by the blue-lined area on the map. This confines the best tornado potential to the southwestern portions of Nebraska, with perhaps a good threat somewhat south along the dryline in the northern half of Kansas. Capping should be in place throughout the warm sector, however, a breakable cap does seem to be indicated by models over the northern half of Kansas and throughout Nebraska in the warm sector. Storm motions are likely to be north/northeastward, with any strong supercells being able to move east/northeast instead. For this reason, the best tornadic target area is likely to be placed in southwestern Nebraska and northern Kansas along the dryline (indicated by black outline). Large hail seemingly will be the main threat of the day, with damaging winds also likely. A lot of time for details in the forecast to be worked out and I will continue to update the forecast tomorrow and on Thursday morning.

Monday, May 19, 2008

TWISTEX Deployment

Latest update from Tim Samaras indicates that TWISTEX will be active beginning Wednesday, and continuing until the trough pattern breaks down. This means an extended period of chasing along the high plains from Wednesday through at least Friday, with the potential to continue chasing into early next week. I will be taking the trip down to Ames tomorrow night, leaving Ames for extreme southwest Nebraska early Wednesday morning.

I've been dealing with computer issues today, backlight on my laptop seems to be failing. So no good forecast update for today, however, tomorrow will feature a nice forecast update for Wednesday and Thursday chases.

You can keep up to date on the latest fielding status updates from TWISTEX on the website.

Sunday, May 18, 2008

Upcoming Week Excitement

We'll start out the week with much less wind than what we saw yesterday over the state, in response we won't warm-up quite as much as when that wind was in place. Highs today over the state of Iowa should range from the mid 60s in the east to the mid 70s along the Missouri. Lows tonight should fall into the 40s to mid 50s from east to west, with clouds and some showers/thunderstorms moving into the state from the northwest. The remainder of the week will be in southerly flow, with a warm front that will slowly move northward and potentially pass through the state during the latter half of the week. Temperatures will be at or above normal, with some impressive moisture making its' way up to the state; currently the GFS wants to paint 70s for dewpoints over the state. More on the system that will effect the plains state in the chasing section below...

Highs for the week will range from the upper 60s to lower 80s from east to west on Monday, the cooler temperatures in the east will be in response to clouds and showers present. Some lingering overnight on Monday, with lows near 50 to the mid 50s from northeast to southwest. Tuesday's highs won't change too much, near 70 in the east to near 80 in the west; lows in the upper 40s to mid 50s from northeast to southwest. Wednesday may be the first of many chances for thunderstorms over the state, with highs ranging from near 70 to near 80 from northeast to southwest; warm front likely just south of the state. The severe weather threat is likely to be minimal with no upper level support and meager moisture. Lows Wednesday night will show the increased moisture, near 50 to near 60 across the state as southerly winds continue just above the surface. Thursday and Friday may be highly variable dependent upon the system's movement, but current forecasts will show mid 70s to mid 80s across the state. Lows overnight in the mid 50s to mid 60s, with dewpoints in the same respect over the state. Chances of thunderstorms have been introduced in the forecast for both days with the warm front lingering around the state, likely draped over the state on Friday. This indicates the best chance for severe weather is likely on Friday with the frontal passage. Saturday may also see warm temperatures and high humidity with more chances of thunderstorms and severe weather. A lot of changes may come into play, likely trimming off precip chances for a night or two and focusing more on one or two of the last four days during the week. More information on the severe weather chances will likely be introduced throughout the week as chasing resumes on the plains.

TWISTEX Update: No official word from Samaras and crew on what the plan may be for the remainder of the week (EDIT: Update received 9:30 this morning with likely operations by Thursday), however severe weather chances look to resume as early as Wednesday and persist through the weekend potentially. Models still having trouble resolving what this deep trough will do, whether it will slowly make its' way onto the plains or if it will cutoff and sit itself down in the southwest. Either way it looks to at least give the high plains some good severe weather chances for a couple of days, with the potential for a threat to move out onto the central plains by Friday/Saturday, etc.

Wednesday looks to have a strong surface low over the high plains of CO/NE with associated warm front and dryline bulging eastward. Moisture likely only into the mid 50s just ahead of the low, but for the high plains this should be sufficient. Shear in the lower levels will also be sufficient for sustaining updrafts, however upper level support could be better. The big wrench in this day may be the increasing temperatures at 850 and 700, potentially meaning we could be looking at elevated, large hailers over western portions of NE/KS and maybe eastern CO. May not be a bad chase day for structure and hail, especially with the target area being in the same area for Thursday's event.

Thursday may be the best day of the system, with forecasted triple point over some part of NE/KS. Sufficient moisture and heating south of the boundary should give way to substantial instability. Although a capping inversion is likely to exist, the combination of heating and the lift with associated waves in the mid-levels should aid in thunderstorm development along the dryline and warm front. The best shear at this point looks to be forecasted along the warm front, or near the triple point. This will lean me to believe the best target area will fall along the KS/NE border (warm front) or northern Kansas (dryline & triple point).

Overall the system may continue to produce severe weather for the week and weekend over the plains states. Low pressure system, warm front and associated cool front will all be potential players in the severe weather setup. A lot of questions still in how the system will evolve and how quick or if the trough will even move out into the plains. Expect daily updates throughout the week on the severe weather threat...

Saturday, May 17, 2008


An amazing spring day yesterday with temperatures rising into the 70s and a few 80s over the state. Strong winds throughout the lower levels, combined with little moisture, allowed for good mixing and heating to allow those temperatures. The same thing should happen today, allowing highs in the mid 70s to lower 80s once again. A few showers or thunderstorms may occur in central and eastern Iowa today as a weak trough continues to progress to the east. The remainder of the weekend will see lows in the mid 40s to near 50 under partly cloudy skies for tonight. Sunday's highs in the mid 60s to mid 70s in response to gusty northwest winds, with the very warm temperatures not far off to the west. Sunday night lows in the mid 40s to lower 50s from northeast to southwest, with the potential for some showers in the western and central portions of the state. The best chance for isolated showers will be over northwestern Iowa; this chance seems conditional given the northwesterly flow and meager moisture over the state. Nonetheless, the forecast calls for at least a chance of some light showers over the state for Sunday night into Monday over the state.

TWISTEX Update: No action over the plains for the next several days as northwesterly flow and ridging is in place and looks to remain. By Tuesday and Wednesday, this ridge will push out onto the central US and a strong trough starts to dig in the mountain-west. This trough has been shown by the EMCWF and GFS with consistency for the past several runs now, and it quite encouraging to a severe weather episode over the plains. The latest news indicates that I as well as Chris Karstens from ISU will be taking ISU's Chevy Cobalt and hitting the road for this journey potentially as soon as Wednesday (maybe Tuesday?) for several days of chasing. With the forecast 144-200+ hours away, not to much for details on the magnitude of the threat and locations. Later updates this weekend and early next week will address more details as the blog will switch over the mainly chase forecasts instead of the general forecasts for Iowa.

Tuesday, May 13, 2008

A Cooler Week

After plenty of rain on Sunday, we've been left with some below normal temperatures for the remainder of the week. Highs from the upper 50s to lower 70s from northwest to southeast today, with gusty winds once again under cloudy skies. Some showers possible throughout the state, with some thunderstorms even in central and eastern Iowa. Southeastern Iowa has the greatest risk for thunderstorms, with some instability present to pose a threat of large hail. These thunderstorms will be numerous this evening and early overnight hours in the eastern third of the state. Lows overnight ranging from the upper 30s to near 50 from northwest to southeast.

Tomorrow will have mostly sunny skies, with highs in the mid 60s to a near 70 throughout. Wednesday night lows in the lower and mid 40s under partly cloudy skies and calm conditions. Thursday will bring the change for a few showers in the west, partly sunny to mostly cloudy skies; highs in the mid to upper 60s. Thursday night lows in the mid 40s throughout the state, with little chances of precipitation. We'll finish off the week with a little warm-up, upper 60s and lower 70s during the day with partly cloudy skies. Lows tonight in the upper 40s and lower 50s with the increasing moisture from westerly winds.

TWISTEX is currently operational in the southern plains today, after Saturday's adventure in eastern Oklahoma where the two mesonets bisected the beginning of a tornadic ground circulation and measured 100+ kt and 60+ kt wind gusts. Today and tomorrow look active for them over parts of TX/OK, then the ridge builds in over the west and provides the plains with nothing but northwesterly flow. Although previous model runs indicated a potential for action returning to the plains by the May 20-24 time frame, latest model runs indicate that this system may become cut-off and pose no threat for severe weather. This may push the next good severe potential until the May 27-29 period over the plains states; well after my tour of duty is expected to be over.

Saturday, May 10, 2008

Summer Plans 2008

Finished my last final ~11:15 AM on Thursday, got back to my apartment to finish packing things and was on my way home in the early afternoon. It is finally summer, but that doesn't mean I'll be taking it too easy for the next 3 months. I'll be running my own business (Jayson Prentice Photography), having an internship (KICD Radio, Spencer, IA), storm chasing (TWISTEX 2008), and probably having an actual job later this summer (Monsanto).

Staring off with my summer plans, I've started up my own 'part-time' business out of my local area of northwest Iowa, Jayson Prentice Photography. I'm offering several of my landscape prints for sale, and outdoor portraits sessions for your family, children, and soon-to-be graduating seniors. I will also be doing a lot of athletics photos of local sports teams, mainly Graettinger/Terril, but potentially others as well if there is interest.

I will once again be 'working' at KICD Radio in Spencer, IA this year. This time around it will be for a college credit internship, so you can expect me to be at the studio there one or two days a week throughout the summer. I'll likely pick days where we can have at least some interesting weather, or the day before so I can have the whole day to forecast the event.

You may remember last June, where I was storm chasing with Tim Samaras and others as a part of TWISTEX. This year TWISTEX is once again back despite funding issues with Iowa State, the ISU Crew will consist of one mesonet car that will mainly be involved with attempts to sample RFD areas of thunderstorms. The car will be under directions from Bruce Lee and Kathy Finley of WindLogics, Inc. Today the TWISTEX crew is down in far eastern Oklahoma where a significant severe weather threat is in place, previous obligations left me unable to chase with them today. However, from Sunday through May 22nd I will be a part of the TWISTEX crew whenever we are active. Currently the first day of chasing for me and the TWISTEX crew looks to be next Tuesday and potentially next Wednesday. Then the flow hits the fan, with northwesterly winds throughout the mid-levels for a majority of my scheduled time with the crew.

A few final things for this summer will include my potential employment at Monsanto for the months of July/August. I worked last year during the pollination season in their test plots, helping them in the process of seed testing. This year I may be a crew leader instead, providing me with a little more money per hour and the ability to be in charge of a few high schoolers ;) .
Another 'job' for this summer will be getting started on my senior thesis that is coming up for my final fall semester as an undergraduate at Iowa State. I will likely be working in collaboration with a current SPC study that is looking at significant tornado outbreak days and some of the conditions that were a part of those outbreaks.

With all of that going on, I'll be sure to put up forecasts for the state and surrounding areas throughout the summer. You'll likely see the blog very busy whenever the threat of severe weather is upon the state of Iowa or anywhere else in the central US if I'm chasing it. Be sure to let me know what you want to hear or what you want to see on the blog by leaving a comment. Enjoy the summer!

Wednesday, May 7, 2008

May 6 Storm Chase Account

While severe thunderstorms moved across the central portion of the state, I decided to take a venture north of Ames mainly in hopes of a good light show to capture. Arrived just to the west of Gilbert, IA last night as the first cell was moving over Story county. Found a photogenic foreground and took this picture of an arcus cloud that was moving southeast with time.

As I listened in to other spotters and the Des Moines NWS via ham radio and the local repeaters I overheard talk of public reports of funnels. I wasn't too far away from the leading edge of the storm and could see some nice scud, but no rotation was evident to me and another spotter even closer to the action also failed to see any rotation. However, a tornado warning was issued for northern Story county on the basis that the potential funnels were there and that a gustnado or two may also be possible with the leading edge. Other chasers/spotters in the area did manage to see a quick gustnado that was formed when a 'cloud' of dust and dirt was lofted into the air. The dirt and dust then appeared to be pulled into the storm via its' inflow. I can see the common misconception of this being a tornado, but it wasn't and good thing too; after all I wasn't there to see it.

Either way, continued to push towards the leading edge and then dropped to the south of Roland, IA and await for the next several cells. With some southward movement to the storms there were finally heading into the Ames area, in which case I called it a chase and headed back to my apartment. Went just outside of town once again in hopes of a secondary line and its' light show, however, it began to weaken along with its' lightning so no images there either.

Total Miles: 45
Total Time: 1 hr 50 min
Highlights: Arcus (Roll) Cloud; Heavy Rain & Minor Urban Flooding

Tuesday, May 6, 2008

May 6 Severe Weather Update #2

Midnight Update: The final update for May 6th and its' severe weather. Another line of thunderstorms is working across central Iowa and is no longer severe, although heavy rain and frequent lightning is still likely. Another line is moving to the northeast, just entered into southwest Iowa where some portions of the line are severe with the possibility of marginally severe hail and damaging winds. This line should continue to move northeast and across portions of the state. A busy day for the state with several lines of severe thunderstorms and even two tornado warnings that were issued, although no reports of tornadoes were received. The northwest quarter of the state was busiest once again, with multiple large hail and damaging wind reports. I will get images from my short chase up tomorrow and report here ASAP! Enjoy the spring thunderstorms...

9:30 PM Update: Warnings continue to be issued for the state of Iowa, mainly for the threat of damaging winds and large hail. We did manage to get a tornado warning for a cell in northern Story county in which I was 'chasing' as the warning was issued. Not much, no rotation spotted from my viewpoint, some nice scud that could confuse the public; a not to shabby shelf before that warning went out. A few pictures that I'll likely post sometime late tonight or tomorrow, awaiting for some stuff to clear out and then for the next line to enter central Iowa for some lightning opportunities. Another nice MCS system that I believe will be the most active severe weather day for Iowa this year; at least in the sense of number of warnings.

7:15 PM Update: The line of thunderstorms still holds potential for damaging winds, latest reports include a 66 mph gust from Mason City airport. Warnings have been issued to cover the complete line from the IA/MN border south and west back to Sac county. Damaging winds look to be the main threat, although the southern cells in Webster and Sac county may still hold a large hail threat.

7 PM Update: A cluster of severe warned cells continues to move across Sac, Calhoun and Webster counties in central Iowa. Large hail up to 1 inch in diameter is possible along with damaging winds. The storms are expected to continue to move east at 30-40 mph through the rest of the evening, however the severe threat at this time seems to be diminishing in all but the southern-most storms.

6:15 PM Update: Severe thunderstorm warnings continue for extreme eastern Woodbury, Ida, Sac, and Calhoun counties. Large hail up to 1 inch in diameter is possible and has been reported. Showers and thunderstorms continuing to the northeast of the current severe warned storms, however these storms are not and are not expected to become severe at this time. Additional thunderstorms still increasing in coverage across Nebraska; another line of thunderstorms, potentially severe, may be possible later this evening and during the early nighttime hours.

5:30 PM Update: A large mess of thunderstorms is occurring west of a Forest City to Sac City line. Some embedded thunderstorms have been severe warned with the threat of large hail and damaging winds. Several reports throughout northwest Iowa of three-quarters to inch diameter hail that has covered the ground. Some wind damage as well, although gusts likely remained below 60 mph. Additional thunderstorms are developing south of the current line of showers and embedded thunderstorms. The first wave of thunderstorms looks to be organizing and should continue across the state through the evening hours. Additional thunderstorms in Nebraska and South Dakota are likely to congeal and pose a second threat of severe weather overnight...

4:30 PM Update: Severe thunderstorms have entered northwest Iowa late this afternoon, first warnings being issued around 3:30 PM for Sioux and Plymouth continues. Currently multiple counties are under warnings for the threat of large hail and damaging winds. O'Brien, Sioux, Plymouth, Cherokee, and norther portions of Woodbury all under a warning currently. These storms are moving to the east at 35-45 mph...

Thunderstorms have continued to develop along the front in Nebraska and South Dakota, which may likely pose a threat to portion of western Iowa later this evening or during the early nighttime hours. Expect frequent thunderstorms with multiple broken lines or individual cells becoming severe throughout the afternoon in northwestern Iowa.

May 6 Severe Weather Update

3 PM Update: Severe Thunderstorm Watch #266 has been issued to include portions of extreme western Iowa until 10 PM.

2:30 PM Update: Severe Thunderstorm Watch #265 remains in effect for portions of northwestern Iowa until 7 PM. Currently a small line of thunderstorms has continued to evolve as it enters a more favorable environment with the latest radar scans indicating continual expansion and strengthening. Currently severe thunderstorm warnings are issued for Yankton county South Dakota, and Cedar county in Nebraska. These two cells should continue to move eastward and cross into the state of Iowa before 4 PM.

More development is expected to the south of this current line and work into the state this afternoon. Both large hail and damaging winds are likely with the storms this afternoon for northwest Iowa.

More thunderstorms will continue to work into the state tonight, with the potential for damaging winds and large hail. Some parts of the state may see more than one round depending on how and where storms develop. More updates as we continue through the afternoon/evening and overnight will address these issues.

May 6 Severe Weather

Severe weather across the state is becoming increasingly likely, with the threats of very large hail and damaging winds now apparent. The SPC has issued a severe thunderstorm watch that covers portions of northwest Iowa until 7 PM this evening. Several cells of thunderstorms are likely this afternoon posting a threat of hail up to 2 inches in diameter and thunderstorm wind gusts upwards of 60 mph. Currently two severe thunderstorms are occurring in southern SD and southwestern MN, both posing a hail and wind threat.

As thunderstorms increase during the afternoon hours and into this evening, expect a complex of storms to begin to work its' way into Iowa. Several other clusters of severe thunderstorms are expected over central and eastern Nebraska, these may also pose a threat during the overnight hours for the state of Iowa. For those of you in Nebraska, large supercells capable of potentially dangerous hail is expected during the afternoon/evening hours. The threat should begin to change to more of a wind threat as storms congeal into an MCS for the overnight.

Heavy rains and potential flooding is another concern for the state of Iowa, to go along with the large hail and damaging winds. More information will be available as storms move into the state this afternoon.

Monday, May 5, 2008

May 6 Severe Weather Threat

It has been a long night of continuous work on school final projects, so not to much time to type things out. Not to mentioned I've typed of 10 pages of work already so the fingers are just kind of gliding across keys in hopes of hitting the right ones...

Severe weather threat for tomorrow looks to mainly be confined to tomorrow nights' MCS event that will roll through ahead of the cold front. A few thunderstorms may form tomorrow afternoon as convective temperatures are reached and the airmass becomes unstable on its' own. However, at this time the thunderstorms will likely be pulse-type in nature with little shear to keep them alive. Maybe a marginally severe hail or wind threat during the afternoon, but the action will likely be in the form of a squall line of some sort overnight on Tuesday into Wednesday.

I will post an update tomorrow morning on the threat for the day, along with what the SPC thinks on the day with their latest outlook. Look for that tomorrow, otherwise enjoy the sunny skies and temperatures in the upper 70s to upper 80s for Tuesday!

Sunday, May 4, 2008

Finals Week Weather

That's right, here at Iowa State we've reached the end of the semester. This week of May is finals week, which of course means that there will be exciting weather to take away from my concentration on what has to be done. This does look to be true, as warm weather and thunderstorms are all likely threats this week.

Today and tomorrow (Monday) look like amazing spring days, no chance of precip and mainly clear skies will help the temperatures warm nicely. Highs today expected to range from the mid 60s to lower 70s from east to west; tomorrow's highs warm even more to the lower 70s to a few 80s from east to west. Lows tonight in the low to mid 40s; Monday night lows in the upper 40s to mid 50s with increasing moisture.

Tuesday is the first day of interesting weather, as a cold front will begin to make its' way across the state during the late afternoon and overnight. Tuesday's highs before the front are expected to be in the mid to upper 70s with increasing moisture. The front should spark thunderstorms across WI/MN/SD/NE and northwestern Iowa during the evening. These thunderstorms are then expected to move east/southeastward throughout the overnight hours. Currently the Storm Prediction Center has labeled the state under a slight risk of severe weather due to this cold front, large hail and damaging winds look to be the threat throughout the overnight hours across the state. Lows will range from the mid 50s to mid 40s as the front moves through and bring cooler temperatures with northerly winds.

This front should stall out south of the state, leaving cool and wet weather for portions of the state on Wednesday as well. Highs on Wednesday should be in the 60s, with showers likely over the southern half of the state. Lows Wednesday night in the 40s with showers continuing over much of the state. By Thursday, only southeastern Iowa is under a chance of rain, however this should only last for the morning hours. Highs in the upper to lower 60s from west to east, with lows Thursday night in the mid to upper 40s throughout the state.

We'll warm up once again with increasing southerly winds and moisture for the end of the week. A chance of showers and thunderstorms also look to come into the forecast for the end of the week. Later updates will focus on the severe thunderstorm threat for Tuesday...

Friday, May 2, 2008

May 2 Severe Weather Update

Several showers and embedded thunderstorms have rolled through the state this morning and early afternoon. Currently these thunderstorms are occurring over Northern Iowa, with one thunderstorm warning issued earlier for Cerro Gordo and Worth counties for damaging winds up to 60 mph. Two reports have came out of that storm, one from Mason City and another from Thompson, IA; both with 60 mph and 59 mph measured wind gusts respectively.

With the lack of sunshine that occurred over the state this afternoon, the severe weather threat looks to have been limited. Extreme northeastern Iowa, mainly along the Mississippi are still in a favorable location for thunderstorms and showers to develop this afternoon/evening. Marginally severe hail and wind gusts are a threat with those storms, however tornadoes are also possible given the relation of the strong low pressure system that will be just to the west/northwest. A Mesoscale Discussion from the Storm Prediction Center indicates that they are watching portions of northeast Iowa, southeast Minnesota, southern Wisconsin and Illinois for the potential of severe weather including tornadoes. There is no watch posted at this time however...

May 2 Severe Weather

Thunderstorms will be widespread across the state today and are already ongoing this morning over eastern Iowa. Another line of thunderstorms/showers is in eastern Nebraska and should move into western Iowa before 10 AM. These thunderstorms should continue into the afternoon hours, where redevelopment is also possible in eastern Iowa along the cold front. The redevelopment of thunderstorms may lead to some isolated severe weather for the eastern third of the state. Main threat with these storms will be marginally severe hail and some strong wind gusts, however, an isolated tornado cannot be ruled out if sufficient heating can take place early this afternoon.

We cool down in the wake of this strong low pressure system, areas of western and central Iowa are already underway with their cool down as the cold front has pushed past and the low continues to pull down cooler air from the northwest and west.

More updates are possible later today if any severe weather is likely to occur

Thursday, May 1, 2008

Northwest Iowa Tornadoes (May 1)

Multiple tornado reports occurred on May 1 in northwest Iowa between 6:50 and 7:45 PM. The tornadoes occurred through Lyon and Sioux counties, near the towns of Rock Rapids, Sioux Center and other nearby towns such as Doon, Inwood, and George. The NWS in Sioux Falls has conducted a survey of the tornadoes, a total of 5 occurred in Sioux and Lyon counties. The longest and strongest tornado is one that began just north of highway B30 west of Carmel, IA and continued to the north/northwest passing just to the west of Rock Valley and finally lifted just south of highway A42, southeast of Inwood. This tornado which featured a path of nearly 13 miles and width of damage of up to 500 feet was rated an EF2 with winds 111 to 135 mph. More information and maps of the path and damage locations can be found on the Sioux Falls NWS Survey Page. In addition, the NWS in Sioux Falls has posted a summary of the events along with a few synoptic reviews as to what occurred in Sioux and Lyon counties.

NWS May 1 Tornadoes & Severe Weather Review

One storm chaser was on this storm and captured the entire life of at least two of the tornadoes, including the large tornado near Rock Valley, IA. Van DeWald, the storm chaser from Omaha, NE made the trip and was the one who captured the images that can be found on his Chase Account Page. He also had a video camera going, in which the video can be found on youtube: Video of the Rock Valley Tornado on May 1, 2008 (~7 PM)
Video copyright Van DeWald

Several pictures from local residents of the tornado and subsequent damage can be found on the KTIV weather blog. A few other pictures from locals can be found throughout the internet, some quick links to some via blogger uploads: Image 1, Image 2, and Image 3.

Other news sources have received some great video and pictures from locals as well. KELO out of Sioux Falls has three public videos that have been uploaded to their website, you can view them here.

The tornadoes from May 1 are unique in the way that they often appeared to be occurring underneath fairly weak showers and thunderstorms. In some cases appearing where there was little reflectivity present on the radar. Some initial statements are accounting these as landspouts, or essentially a tornado that is not associated with a thunderstorm's rotation. Early indications do show that there was strong rotation on KFSD radar, at least at the lowest level. I will be looking into the storms to see how extended this rotation was into the storm, but currently FSD NWS is calling these tornadoes instead of landspouts. I will post any future information on my findings in the coming days here...

8:00 AM May 2 Update: I've updated the post above with a few more screen grabs from Van DeWald's video camera and the video that he captured.
Also have a few images via KTIV that local residents sent in last night and this morning that were added.

May 2 Afternoon Update: Rearranged the post a bit, included new information and added in a link to the Sioux Falls NWS page they have about the event. Also more local images and video links were added.

5:30 PM May 2 Update: The Sioux Falls NWS has completed their survey of the tornadoes in northwest Iowa, this information was added to the page.

May 1 Severe Weather Update #2

I took a small trip outside of Ames late this afternoon/evening in hopes of some thunderstorms along a surging dryline in central Iowa. A nice CU field was present, and several towers tried to get going, but to no avail as they were all crushed by warm temperatures aloft. This wasn't the case in extreme northwest Iowa, as a strong dynamically driven system combined with the low pressure in the vicinity to create a favorable environment for rotating storms.

The first tornado report in Iowa came just before 7 PM near Sioux Center. As the storms continued to develop and grow, several more tornadoes were reported in Sioux and Lyon counties through 7:45 PM. The only damage report thus far was near Rock Valley where it hit a farmsted to the west of town. The second-hand report indicated that several buildings may have been hit, however the house looked okay. More detailed reports on those storms and subsequent tornadoes once Sioux Falls NWS conducts surveys and more images of the tornado(s) are available.

Currently the dryline is stalling out in central Iowa and may retrograde (move west) overnight tonight. Several isolated thunderstorms occurring central and eastern Iowa, with one severe thunderstorm warned storm in Black Hawk and Bremer counties. Quarter-sized hail is possible with that storm through 10 PM.

Other areas in the central US are still being pounded by severe and tornado warned storms, from central Oklahoma through eastern Kansas and into northern Missouri. These storms should continue to move north/northeast and into the state of Iowa during the overnight hours likely effecting mainly the eastern half of the state. These thunderstorms should move out during the morning hours, in time for another round potentially in the afternoon for eastern Iowa. Once again severe weather is a possibility for those storms in the eastern half of the state tomorrow afternoon, the best threat will likely be near the low pressure system center that may be somewhere in northeast Iowa. Once more information is known on the possible location of this low and the severe weather threat, later updates may relay that information.

May 1 Severe Weather Update

Currently going through a complicated forecast scenario for the central plains, with the potential for large hail, damaging winds and isolated tornadoes. Latest forecasts indicate that western Iowa is now becoming a more favorable target than previously thought, this will not only include southwestern Iowa, but northwest Iowa as well. Several ISU crew vehicles are hitting the road within the next hour heading towards western Iowa. Once again, stuck in class until ~5 PM, but will then make a decision with a 'local' chase not out of the question for this evening. Might not have another update on the blog until late this evening or after class depending on how the situation looks. The western third of the state of Iowa should be alert though this evening for the potential for severe weather...

May 1 Severe Weather Threat

Severe weather is likely over portions of the central plains, with all modes of severe weather (tornadoes, hail, and wind) possible. A strong low pressure system associated will begin to be cut-off during the late hours of the day. This low will be responsible for the setup of a triple point over some portion of either southeastern NE or eastern KS during the evening hours. The dryline and warm front intersection may be a key positioning for any severe weather initiation before midnight. As we head into th later nighttime hours, a cold front further to the west will begin to overtake the dryline and likely initiate convection in mainly linear form across the plains.

Several concerns still exist with the setup for severe weather, one being moisture return and the other being warm temperatures aloft creating a cap over the plains. The capping problem is a definite concern for the southern portion of the current outlook (southern KS and OK) where storms may not be able to initiate until the cold frontal passage ~Midnight. To the north, less moisture may exist, however cooling in the mid-levels may still weaken the cap enough to initiate convection during the late evening hours.

As far as chasing this setup, I am unable to be out of Ames until 5 PM. This limits me extensively on where I can be in time for a good storm. Depending on how things do look when my day on-campus ends, I will consider heading out locally. I may end up waiting for more of a linear mess to come to me during the early morning hours, as I could definitely use some lightning picture opportunities as I've missed the last few. More updates on my chase potential as well as the entire system in later updates during the day...

12:45 AM Update: SPC Day 1 will initially includes a large portion of the state under a slight risk of severe weather; areas west of a Mason City to Waterloo to Keokuk line. This slight risk is maximized for areas of southwestern Iowa, where the potential for tornadoes and large hail is greatest. Although current SPC wording doesn't indicate a lot of potential, not sure if I want to believe that currently. Later SPC updates may prove otherwise with an increased threat and potential moderate risk if moisture return can be realized...