Severe Weather Possible (Feb 20)
Posted: Sun Feb 20, 2005 1:45 pm
From the latest outlooks, there is a slight risk area still covering portions of the mississippi valley and the ohio valley. More specifically areas of southern IL/southern IN, western KY/western TN, extreme northwest LA, all of AR, as well as the south/southeastern portions of MO.
The reason for this slight risk is for a cold front that will slowly be makings its way across the plains. This front combined with a shortwave trough and the low pressure that will be over the OH/IN areas by tonight should all combine to produce considerable lift for storms. A large plume of warm air and moisture will be in place, which will allow CAPE values to reach around the 1500-2000 J/kg. Lapse rates will be on the increase, as well as considerable shear will be in place.
With these storms, large hail will undoubtably be the highest threat, but with CAPE being quite high an isolated supercell cannot be ruled out. And if the CAPE can raise any higher then more supercells will be likely. With any supercell that develops, high wind and an isolated tornado cannot be ruled out. The area that will be in the greatest risk of seeing some supercells will be the MO/AR/IL/KY/TN areas late this afternoon/evening.
The reason for this slight risk is for a cold front that will slowly be makings its way across the plains. This front combined with a shortwave trough and the low pressure that will be over the OH/IN areas by tonight should all combine to produce considerable lift for storms. A large plume of warm air and moisture will be in place, which will allow CAPE values to reach around the 1500-2000 J/kg. Lapse rates will be on the increase, as well as considerable shear will be in place.
With these storms, large hail will undoubtably be the highest threat, but with CAPE being quite high an isolated supercell cannot be ruled out. And if the CAPE can raise any higher then more supercells will be likely. With any supercell that develops, high wind and an isolated tornado cannot be ruled out. The area that will be in the greatest risk of seeing some supercells will be the MO/AR/IL/KY/TN areas late this afternoon/evening.