SPC Issues Mesoscale Discussion That Includes the NE Corner of Alabama

SUMMARY…Storms capable of producing mainly isolated damaging winds should persist through the early evening. Watch issuance appears unlikely at this time.

DISCUSSION…Convection that has formed along the spine of the southern/central Appalachians this afternoon should continue to spread generally eastward as a weak upper trough persists over the eastern CONUS. The area from northern GA into central VA has become moderately unstable owing to diurnal heating of a rather moist low-level airmass, with MLCAPE 1500-2500+ J/kg estimated by the latest mesoanalysis. A nearly stationary surface front was also analyzed across this region. Additional storms may form along this boundary through the early afternoon. Low-level flow is expected to remain weak, but around 20-30 kt of southwesterly mid-level winds and similar values of effective bulk shear should promote modest storm organization.

Clusters and multicells should be the dominant storm modes, with steepened low-level lapse rates encouraging strong/gusty downdraft winds to the surface. Current expectations are for most of these winds to remain sub-severe, but isolated damaging wind gusts may still occur with the stronger storms. Slightly better mid-level flow is forecast to be present over parts of southern/central VA in the vicinity of the weak stalled front. A greater concentration of storms may ultimately materialize through the early evening across this region, perhaps posing a slightly better chance for severe wind gusts. Regardless, the overall severe threat still appears fairly marginal/isolated, with watch issuance unlikely at this time.

Information from SPC Mesoscale Discussion 1411 issued at 1:08 pm.

Category: Alabama's Weather, ALL POSTS, Severe Weather