Skip Talbot
EF5
A potent setup for some severe weather across the MS and OH rivers tomorrow with some modest instability and insane-o shear. Models have been consistent in deepening and ejecting a surface low into Canada on Friday with 60's dews advecting as far north as the OH river followed by a fast moving cold front under a 100 knot midlevel trough.
Storms look to be ongoing overnight/during the morning as the cap is wide open over MO with ample lift in place. I'd expect mainly a linear, messy line of rain and storms on the cold front on the northern end of the cold front near the surface low. Capping may keep storms more discrete further south.
From a chasing standpoint, this setup doesn't look too attractive to me with an excessive amount of forcing, undercutting from the cold front, and fast storm speeds over the unfavorable terrain of the MS/OH river valleys (except maybe on the eastern flood plain). Still, helicity ahead of the cold front is extremely pronounced. The NAM has been showing over 500 m2/s2 effective srh ahead of the cold front the past couple runs:
If you could get a discrete storm to go up ahead of the cold front, the extreme srh could more than make up for the modest instability and you could see some tornadoes. That's always a gamble though, and there may not be enough lift as the bulk of the upper level energy is still behind the cold front at 21z. Still, the jet isn't quite parallel to the front, so a shortwave downstream or some divergence aloft might be able to pop up a few cells downstream. I'd definitely keep an eye on that if I was on the OH river.
Otherwise, I think the best bet for tornadoes might be further south and during the evening when the shear values continue to increase and hodographs enlarge: From KY down into MS with embedded or semi discrete supercells. This assumes the warm sector isn't completely socked in with crapvection as I expect the northern part of the cold front will be up in Illinois/Indiana. The southern end in Dixie Alley may have a few more breaks in the line allowing for some supercell organization.
Looks like a day to get to your spotting location if you live near the OH and MS river valleys. Or an equipment test. I don't see this as a real chase setup though given the likely embedded storm mode, fast storm speeds from that 90-100 knot trough, and unfavorable terrain.
Storms look to be ongoing overnight/during the morning as the cap is wide open over MO with ample lift in place. I'd expect mainly a linear, messy line of rain and storms on the cold front on the northern end of the cold front near the surface low. Capping may keep storms more discrete further south.
From a chasing standpoint, this setup doesn't look too attractive to me with an excessive amount of forcing, undercutting from the cold front, and fast storm speeds over the unfavorable terrain of the MS/OH river valleys (except maybe on the eastern flood plain). Still, helicity ahead of the cold front is extremely pronounced. The NAM has been showing over 500 m2/s2 effective srh ahead of the cold front the past couple runs:
If you could get a discrete storm to go up ahead of the cold front, the extreme srh could more than make up for the modest instability and you could see some tornadoes. That's always a gamble though, and there may not be enough lift as the bulk of the upper level energy is still behind the cold front at 21z. Still, the jet isn't quite parallel to the front, so a shortwave downstream or some divergence aloft might be able to pop up a few cells downstream. I'd definitely keep an eye on that if I was on the OH river.
Otherwise, I think the best bet for tornadoes might be further south and during the evening when the shear values continue to increase and hodographs enlarge: From KY down into MS with embedded or semi discrete supercells. This assumes the warm sector isn't completely socked in with crapvection as I expect the northern part of the cold front will be up in Illinois/Indiana. The southern end in Dixie Alley may have a few more breaks in the line allowing for some supercell organization.
Looks like a day to get to your spotting location if you live near the OH and MS river valleys. Or an equipment test. I don't see this as a real chase setup though given the likely embedded storm mode, fast storm speeds from that 90-100 knot trough, and unfavorable terrain.
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