Tomorrow (2/24) is looking like a no-brainer chase day. If anything the models overnight became even more optimistic about severe weather here in Virginia. This is the 0-3 km energy-helicity index for 1 pm tomorrow per the 06Z GFS:
Clicking on the handy-dandy Pivotal Weather map at Danville provides a very severe weatherish sounding for any time of year, much less late February. GFS has CAPE values approaching 1000 j/kg and shear values in the insane range (40 kts at 0-1 km) with lifted condensation levels of a few hundred meters. These of course lead to very favorable supercell composite and significant tornado parameters.
And then there’s the always optimistic 4km NAM…which is almost literally shrieking SEVERE WEATHER AHEAD!!! The good news for model agreement is that the NAM, the Euro, and the GFS are all showing the wedge breaking down across much of Virginia by the noon hour. That could still be a bit early given the stubborn nature of cold air damming wedges here in the Mid-Atlantic but that’s the nature of the beast.
The NAM is about 3 hours slower in bringing the main dynamics into the region (one factor of which is an incredibly strong 500 mb jet streak) than the other models. But given predicted storm motions of 60-70 kts I will likely be in place somewhere along the U.S. Rte 29 corridor by noon regardless of the timing differences in the models. Of course the HRRR and RAP short range models will come into play tomorrow morning as well.
Right now this is the Day 2 convective outlook from the Storm Prediction Center: If the dynamics continue to look this robust I wouldn’t be surprised to see the Slight Risk area moved westward in today’s 1730Z update as well as an expansion of the Enhanced Risk area into southeastern Virginia. And I wouldn’t rule out an Enhanced Risk in south-central VA in tomorrow’s Day 1 outlook.
Now it’s time to prepare the chase gear!