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.

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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.

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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.

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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

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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.

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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.

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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.

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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.

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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 www.twistex.org website.

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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...

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Summer!

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.

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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.

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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!

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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

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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.

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