May 22 has historically been a good date for my chasing (2004, 2007 were both very good tornado intercepts). This year, I’ll be backing to chase May 23-?, depending on the weather.
SPC has issued a Moderate Risk and a Public Severe Weather Outlook for today. There is a 15% hatched tornado ring for much of the upper midwest (IL, IA, WI, MN, MO).
From the SPC comp map, there is a 300mb jetstreak across TX/OK, and the 850mb winds are at a slight angle to the jetstreak.
In the moderate risk area, the 300mb winds and the 850mb winds coincide. Any shear must be because of different velocities, or because the 300mb winds will move as the upper level low tracks eastward by the afternoon.
There is a distinct dryline running from TX to approximately the IA/MO border, where it begins to fan out a bit. It coincides with a
cold front that SPC expects to become occluded. There is ample moisture on the wet side of this dryline.
It’s kind of a weak prediction today- the kind that I can only get away with on the computer, but I am going to pick a few places in two areas that I could not drive between in a day. I chose TX/OK due to the frontal boundary, dryline and jetstreak all in the same area, and I chose Leon, IA because it is at the north end of the dryline, and the southeast part of the upper level low. I could never get between TX and IA in time if I was wrong, but I can do this from my computer. I’ll try to up the quality of my forecasts in the future…
1. Wichita Falls, TX
2. Oklahoma City, OK
3. Leon, IA
High Plains Chasing 