|Wednesday, April 21, 2010 - 11:25AM CDT
Forecast update III for April 22-24
|2010 Storm Expeditions - Probabilities as of April 21|
Update 11:25AM CDT Tuesday: 12z NAM continues to not show any real reason to not expedition tomorrow and Friday. So, the trip is a go, barring unforseen cirumstances. My only concern about Friday is that the warm front here at home in eastern MO/SW IL may be a viable play for tornadoes, so much so that I might have to make a marathon drive back here after Thursday's expedition (I hate to miss potential tornado events close to home, even if something better is elsewhere). Oklahoma also looks good on Friday, so if it keeps that way I might stay out. A drive to Memphis on Saturday may be in the cards also.
Update 9:53PM CDT Tuesday: The 00z NAM hasn't changed things much. This is looking more like a go - initiation won't be an issue (there will be storms), and enough ingredients are in place to make for a decent tornado threat. Still a lot of time for changes, but looks like the venerable old observer convergence town of Shamrock, TX (I-40 near TX/OK border) may be the tentative starting point on Thursday morning. Unless the 12z models go haywire tomorrow, I'll probably head west by mid-afternoon.
Update 2:27PM CDT Tuesday: The 12z NAM, GFS and Euro models are in good agreement in maintaining the parameters on the dryline for Thursday in terms of upper support, low-level wind fields (850mb to surface), moisture, and convective inititation. As a result, I've increased the Plains expedition day probabilities for this week to 75%. The plan, Lord willing, is to leave after the 00z model runs Wednesday evening, with a stopover somewhere around the Joplin/Tulsa areas - then heading west on I-40 to the TX/OK border Thursday morning. It's too far out to call specifics, but the early-day target will probably be north and west of the I-40/TX/OK border intersection point. If the models stay consistent, I might leave earlier in the afternoon to make the drive easier. Waiting until late evening would give the models and realtime data a chance to hint that the setup was headed for the trash at the last minute - but I don't see that happening this time. I'll be worried only if there aren't deep 60+F dewpoints well on their way to the target area by late afternoon tomorrow.