April 7, 2008
Southwest Oklahoma/Northwest Texas
Editor: Putnam E. Reiter
Risk Area: Slight Risk
Initial Target Area: Lawton, Oklahoma
A strong cold front moved through the region a few days before this event, so moisture return was questionable. However, time of year and presence of strong flow aloft, indicated there was potential for severe weather. Unfortunately it wasn’t as good as thought.
The setup had a developing trof in the western U.S. that was to move eastward into the region. The timing was off and as noted moisture wasn’t that good. Moisture did rapidly increase during the day with common upper 50s dewpoints and a few areas of low 60s. The warm front ended up in central Oklahoma with a dryline in SW OK/NW Texas when storms developed.
The warm front was of interest given that it was a good boundary, but the dryline showed potential. CAPE values were around 2500 J/Kg and LIs to -7 across parts of SW OK/NW TX. Winds aloft were quite favorable for rotating updrafts and organized severe thunderstorms. The timing of the event seemed well-timed as all the models showed development during the afternoon hours.
Storms developed on cue around 16:00 and SPC already had a PDS tornado watch up for the area. Additionally, they upgraded the slight risk to a moderate. At first a cluster of storms developed in NW Texas, but eventually a single supercell emerged. This storm moved east near Electra and produced a tornado. Other storms tried to develop, but failed to do so. The Electra storm continued east and about the time it reach I-44, north of Wichita Falls, it died.
Other storms developed farther south in NW Texas, with these storms primarily producing large hail. The warm front had moved to north Central Oklahoma where several supercells developed along this boundary and moved into northeast Oklahoma.
Hook-Echo Discussions – see the blog, sequence number is 2008-8-X
The Chase –
Team 1 – David Underwood, Rob Ferguson, and Putnam Reiter
Miles Driven – 275
Departure Time – 15:00 CDT
Return Time – 20:00 CDT
We left Oklahoma City and headed south on I-44 towards Lawton, our original target. We sat in Lawton as the storm by Electra developed and organized into a supercell. We could tell that the Weather Service was interested in this storm. However, we thought a storm was developing near Davidson and decided to go look at it. So, we left our area just north of Lawton and drove south on I-44 to HWY 62 and then went west. As we got west of Lawton we noticed the storm near Davidson was gone, so we decided that the one in Texas might be the better bet. However, at this point we couldn’t easily get there.
So, we turned south on Deyo Mission RD from Deyo and hooked up on HWY 36 south through Faxon to Grandfield and turned west on HWY 70. As we got close to Davison, we saw the area of development just to our north. We also noticed that the storm in NW Texas wasn’t doing as good. So, we went north on HWY 183 to Fredrick and then east on HWY 5 to get a better look at the storms near Cache. We drove back to HWY 36 and went north to just past Faxon. We stopped there for about 20 minutes and decided to continue on east.
The storms in Oklahoma were not doing very well and by this time the storm in Texas was about gone. Two other storms had developed in NW TX and looked impressive on RADAR. We hit I-44 and head back north. Drove through some rain north of Lawton and that was about it. We kept on going north to home.
Lessons Learned –
– Forecasting: It wasn’t the best day in the world, but worth going out on. Moisture was the real issue, but it happens in April. It would have been better with the upper system closer.
– Positioning: This isn’t something to complain about, but could have gone to Texas. Many other people stayed in Oklahoma and the Texas storm did its thing pretty fast.