10.21.10
Friday’s Severe Weather Forecast
There’s a slight chance for some severe weather this afternoon in west Texas into eastern New Mexico, including a chance for supercells, but today I’m going to focus on the risk for severe weather tomorrow.
I had a quick look at the 12Z GFS and NAM, and this is what I’m seeing.
There’s a stacked, closed low over Arizona right now, expected to move into eastern Colorado by tomorrow evening. Dewpoints are forecast to reach the lower 60s from Texas up into south central Kansas as surface winds will be from the south-southeast and a cold front / dryline will set up in the east Texas Panhandle. Although there will not be a ton of instability along the dryline, with CAPE values likely only in the 500 to 1500 J/kg range, there will also not be much of a cap. There will be positive vorticity advection in western Oklahoma and ample wind shear for rotating storms (the NAM has 0 to 1 km SRH of 100 to 150; the GFS and NAM have 0 to 6 km bulk shear of 35 to 50 knots centered around Wichita Falls, Texas). Hodographs in parts of western Oklahoma look pretty curved.
The primary limiting factor for severe weather is the lack of instability, largely caused by cloud cover. If sufficient heating is there for surface-based storms to form, there will be enough lift and wind shear to get some supercells and possibly even tornadoes.
There could be two plays on this setup: the possibly more obvious one, from around Lawton, Oklahoma to Wichita Falls, Texas…instability could be greater there and upper-level winds are stronger. The other target I’m looking at is in northwest Oklahoma, closer to the low. There could be enhanced lift there (as well as steeper mid-level lapse rates), enough to overcome the lack of instability.
Bottom line: there could be a decent chance for supercells tomorrow from northern Texas (Wichita Falls area) all the way up through western Oklahoma and possibly even southwest Kansas. If conditions improve by 1pm tomorrow, I may go out chasing…provided that I can make it to my target on time. I’m having lunch with a group of students and a prospective grad student until 1, so I can’t leave before then anyway.
Stay tuned!
