Severe Weather Tonight?

Should you be worried about severe weather across North and Central Alabama overnight?

Based on the effect of the strong easterly wedge that has brought cool, damp air to the area today…chances are greatly diminished. And they weren’t very high to start with. But having said that…temperatures and dewpoints will rise overnight as a strong low level jet develops, pulling warmer, moist air quickly northward.

TO THE WEST AT THIS HOUR
A solid line of thunderstorms has developed from west of Camden Arkansas to the Shreveport area then becoming broken into eastern Texas to east of Lufkin. Dewpoints in the lower 60s have spread as far north at Natchitoches, LA, south of Shreveport. Even in Louisiana though, CAPES are limited to 500 j/kg over a small area north of Lake Charles.

The storms are being sparked by a strong upper trough that is swinging eastward, which is overcoming the lack of CAPE. Strong wind fields aloft will allow for the potential for damaging wind gusts as the line moves across Louisiana and Arkansas. The potential for severe weather will diminish as the storms approach the Mississippi River.

This line will reach western Alabama around 2-3 a.m. and the Birmingham area around 4-5 a.m.

Temperatures should rise late tonight, reaching the upper 50s or even lower 60s by morning. Dewpoints will reach the upper 50s to near 60.

Still, instability will be nearly non-existent. Lifted index values will only be the slightest bit negative. But with the strong forcing, the narrow line of storms should hold together, feeding on the meager instability that is pulled northward just ahead of the line.

Winds will be very strong just above the surface, with winds at 5000 feet projected by the GFS to be around 70 mph. This means that strong winds will be easily transported to the surface by any updrafts that can hold together. There could be some hail as well.

There shouldn’t be enough instability for there to be any tornado threat.

Outside thunderstorms, surface winds will average 15-25 mph with higher gusts. There could be quite a few reports of minor wind damage outside thunderstorms tonight due to these gradient winds.

SO BOTTOM LINE
No widespread severe weather is expected overnight. Any watches should stay to our west. There could be a few warnings with the line in Alabama after midnight, with the main threat being damaging winds, but this should be isolated. Minor wind damage up trees being uprooted could occur outside thunderstorms as winds pick up.

The rain will move east during the morning hours on Sunday, with the main rain over by lunch. But, like Thursday, we could see some thunderstorm redevelopment Sunday afternoon. Any that do will be very isolated.

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