The rest of this week has quite the change with a return to more of our typical Spring severe weather season. You may have already noticed the increase in humidity along with 50 mph wind gusts!
A zonal flow in the Jetstream will send a few upper disturbances our way to interact with a slow moving cold front across the state. This is going to allow flash flooding to develop across C OK, which does include the greater OKC metro area. Along with the heavy rainfall, there will be reports of damaging wind, large hail in excess of 3″ in diameter and a couple of tornadoes. The best location for anything tornadic will be any supercell anchored to the cold front boundary. So watch that position closely on Tuesday and perhaps Wednesday as well. On Tuesday it will be draped across NE to SW OK, and on Wednesday roughly E/W along I-40. Tap the map below to animate the storms. The storms that develop in the late afternoon will continue overnight Tuesday into Wednesday across the N half of Oklahoma, and then develop across the S half Wednesday afternoon and evening. All storm activity will wind down by late Wednesday night.
Storm animation through Wednesday afternoon.
The helicity output from the models does suggest there will be supercell storms with very large hail. Models won’t be able to pick the exact location of the strongest helicity track, so the take home is that any storm in the vicinity of the front on Tuesday will be capable of the hail and tornado threat. Again rainfall amounts will be excessive and the global output below from the GFS could be underdoing it just a bit, meaning amounts may end up with 7″ or greater.
Helicity output of rotating storms.
Total Rainfall Midweek
I can’t rule out a stray shower or storm Thursday and Friday, but the next big threat for severe weather will be Saturday and Sunday as the CAPE/Shear is adequate for severe storms again. We’ll have more on that later.
Instability for Saturday.
Instability for Sunday.
The temperature trend will be to cool things down midweek and then heat it back up for the weekend. We may be in a stormy pattern the following week as well. -AT
OKC Temperature Trend.
