5/3 - 3pm - Flooding, Late Week Severe Weather, Storm Chasing

The rain that caused massive flooding in Nashville and elsewhere around the Southeast is finally out of here. The pictures coming out of Nashville, where 13.53" of rain fell at the airport this weekend, are just incredible, including this shot of the now-evacuated Gaylord Opryland Hotel and Convention Center:

(Photo Credit: Erin Davison)

More flooding problems could be on the way for areas on Nashville on the Cumberland River as it crests this afternoon. The death toll from this weekend's storms and flooding across Tennessee, Kentucky, and Mississippi stands at 21.

As this weekend's weather event wraps up, we now turn to later this week in the Ohio Valley. The Storm Prediction Center put all of Kentucky, Indiana, Ohio, and West Virginia, along with parts of Michigan, Tennessee, Illinois, Missouri, and Pennsylvania in a 30% risk for severe weather on Friday:

Here's what the SPC is saying about this event on Friday:

IT STILL APPEARS THAT A STRONG WIND FIELD WILL OVERSPREAD A MOIST AND UNSTABLE WARM SECTOR IN PLACE OVER THE OH VALLEY INTO LOWER GREAT LAKES.  HERE...ENVIRONMENTAL PARAMETERS WILL BE QUITE OPTIMAL FOR SUPERCELLS AND/OR A LARGE-SCALE LINEAR CONVECTIVE SYSTEM WITH THE THREAT FOR WIDESPREAD SEVERE WEATHER.

The GFS model seems to support these assertions with ample shear and the presence of upper-level divergence on the 500mb chart (causes uplift in the atmosphere... crucial for storm development):

The NAM model will chime in on this event tomorrow, which means we will have a better handle on what kind of instability and winds we'll be dealing with. I will say that moisture will not be a limiting factor for severe weather on Friday as dewpoints will most likely be in the 60's. There could be a few severe storms around the area on Thursday and Thursday night as the cold front with this system approaches the area, but limited shear will keep a lid on that potential.

The ironic thing about this Friday severe weather is that I'm leaving for Amarillo the next day to start my storm chasing trip. The start of the tornado season in the Plains has been very slow because of limited Gulf moisture, but now that temperatures in the Gulf have risen, I think things will begin to pick up pretty quickly. This week will be fairly quiet due to a west-east zonal flow across the US, but next week a disturbance in California will bring back the much-needed southwest winds to the Plains. Here's what the GFS is putting out for May 10th (my second day of storm chasing) in terms of instability and moisture:

Notice how the CAPE (instability) goes well over 2000 J/kg on the TX/OK border in the image on the left and how dewpoints will be approaching the 70 degree mark in the image on the right. These two factors are very good for severe weather in both TX and OK, so our Todd (our tour leader at Storm Chasing Adventure Tours) and I are really going to have to watch the development of this situation as next week approaches. Storm Chasing Adventure Tours started the first tour of the season yesterday by driving from Amarillo, TX to Meridian, MS to see some severe storms around South Mississippi. Even though the zonal flow this week won't be conducive for any widespread severe weather, I'm sure it'll be a fun tour. I'll be out there on Tours 2-5 (May 8th - June 5th), so don't forget to check out the blog for videos, pictures, and updates!