| Chase Day: April 25, 2009 |
| Written by Chris Nuttall | ||||||||||
| Thursday, 30 April 2009 | ||||||||||
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The upper-level pattern was characterized by a broad, stationary trough over the western CONUS. Over the next week, several short-wave trough would rotate around the main trough and move through the southern jet stream causing several severe events over the Southern Plains. Today would be the first day. Moist air from the Gulf of Mexico had been steadily streaming northward across the Southern Plains for 2-3 days. Locations east of the Caprock in Texas (and farther east into Oklahoma) had dewpoints well into the 60s. Veering wind fields with height also promoted rotating storms with the possibility of tornadoes. Cold temperatures aloft suggested the large hail was also likely. However, an advancing cold front from the Northern and Central Plains was complicating matters. The key to the whole day was how far south would the cold front make it. In the preceding week, the GFS was blowing the cold front all the way to the Hill Country of Texas. Subsequent runs began slowing the cold front down and eventually stalling it somewhere across the northern Texas Panhandle. The NAM was taking the cold front through most of the Texas Panhandle, stalled it along a line from Friona-Tulia-Wheeler-Gage. Only time would tell which model would verify. However, in both situations, a dryline was progged to set up just along the Caprock with the triple point setting up somewhere in the area of the NE Texas Panhandle. I was off work this day, and the proximity of the target zone provided a perfect opportunity for me to log my first chase of the year.
Target: Wheeler, TX
2:45pm CDT (1945z) After suffering some equipment hiccups, I decided to pull over at the rest area between Groom and Alan Reed to get everything sorted out. While dealing with that, I started to notice several cumulus towers begin to build to my southwest, as well as overhead. I saw Steve Miller (TX) pass me on I-40 headed east, so I decided to give him a call and see if he wanted to convoy today. I don't like 3-4 car convoys, but prefer to have 1 other vehicle along in case somebody suffers car trouble. Gives me piece of mind.
3:19pm CDT (2019z)
Turned east on TX-152 for a few miles before reaching a roadside picnic area. I was immediately south of Storm-A and pulled over to take a look. Steve and I experienced some pretty strong southerly winds. In a field about 500 yards to our south, we could see dust blowing from west to east. Looking overhead, there was some pretty violently rotating scud. About 30-45 seconds later, we had a cold northwest wind. There were also a couple of strong dust whirls (about 3-4 feet wide) within about 20-30 feet of us. We decided to quickly bail east and were blasted with more strong inflow winds from the southeast.
I stopped about 4 miles ENE of Briscoe to watch the storm. I continued to follow the storm east towards Allison. I opted to take a dirt road east from here to avoid the hail core, eventually reaching State Highway 47 and taking that east towards Reydon, OK, before turning north on OK-30.
6:30pm CDT (2330z) I continued to follow Storm-A and turned east on OK-33. At Roll, I had to take some more dirt roads in order to keep in good position on the storm. The Canadian River made it impossible to get any closer than about 5 miles. Storm-A started to merge with other convection that had developed farther to the east, and really started to lose definition. Steve and I debated bailing and heading for some more impressive storms to the south. However, with sunset less than 2 hours away, our chances of making it were slim, so we decided to keep with our current storm.
7:55pm CDT (0055z)
Several wall clouds and funnels developed and dissipated over the course of the next 30-45 minutes. Some of them were quite impressive, however nothing ever touched the ground (2.4MB). Steve was much closer to the storm than I was, and he also verified this. I continued watching Storm-A from this position as it cross the highway and eventually moved away to the northeast. It was quickly getting dark, and I met up with Steve in Leedy to make the drive back home. We spent the trip discussing the day's events, what could have prevented tornado formation, and the forecast for the next day.
SUMMARY:
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| Last Updated ( Saturday, 24 July 2010 ) | ||||||||||