A Few Notes Just After 6:30 a.m.

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We have been tracking severe thunderstorms since around 4 a.m. this morning and will be doing so for another 18 hours or so I am afraid. No warnings are in effect at this moment.

Impressive boundary across the South this morning. You can see it in the top left panel of the graphic. It extends along the Red River between Texas/Oklahoma eastward along the Louisiana/Arkansas order then to a weak surface low near Greenwood MS then along US-278 in Alabama to near Atlanta, then to another surface low in northwestern South Carolina and out into the Atlantic.

Lots of very moist air to the south of this boundary as you can see in the lower left panel, which also has the SPC slight risk severe weather outlook superimposed on it. Look for portions of this outlook area to be possibly upgraded to a moderate risk later this morning. The next severe weather outlook will be issued around 8 a.m.

This boundary will be the focus for active weather all day today. See the radar echoes in the right panel? They are a product of the rapid moistening of the atmosphere, the low and the boundary. The dewpoint at Tuscaloosa has risen from 46F at 1 a.m. to 58F at 6 a.m. The dewpoint at Jackson is 65F and 70F at Baton Rouge! This moisture will continue flowing northeastward today below the frontal boundary, which should lift a little to the north during the day.

The surface low near Greenwood is stirring up the trouble early this morning. It will continue eastward, producing strong to severe storms as it does. The main threats now are hail and damaging winds. As the low passes across North Alabama and we get some surface heating this morning, the storms will become surface based instead of elevated, and tornadoes will become a problem, first over the Tennessee Valley.

Heavy rainfall already has been a problem in places like northern Marion and Winston Counties and will be an increasing problems as heavy rainfall continues to train across the northern quarter of the state for several more hours.

Additional severe storms will form across Central Alabama, starting over western sections by later morning. This will move east and southeast, reaching the I-59 corridor by early afternoon and progressing southeastward slowly through the rest of the afternoon. There is a potential for tornadoes with this activity.

To the west, a surface low near Wichita Falls, Texas will also move east or northeast today. As it does, it will produce another round of strong to severe storms this evening across North Alabama, mainly north of a line from Carrollton to Alabaster to Roanoke. The bad news is that these storms may produce tornadoes as well. The good news is that this activity will slowly weaken as we lose the heating of the day and by midnight, we should just see a weakening line of showers and storms pushing southeast as the low moves off to the east.

IN SUMMARY…
…storms will continue along the frontal boundary over North Alabama through early afternoon. They will be strong to severe with damaging wind, hail and eventually tornadoes.
…more storms will form over Central Alabama later this morning (after 10 a.m.). They will push slowly east and southeast. They will be heaviest in the I-59 corridor during the early afternoon (1-3 p.m.) and southeast of there from 3-6 p.m.
…the last round of storms will form over Northwest Alabama after 6 p.m., affecting the northern third of the state, mainly north of a line from Carrollton to Alabaster to Roanoke through 2 a.m.
…a weakening line of showers and storms will push southeastward after that ahead of a cold front.

THREATS…
All modes of severe weather are possible today and tonight across Alabama, including tornadoes, damaging winds, flooding rains and deadly lightning. Stay in touch with reliable sources of weather information as you go through the day today and into the overnight hours.

We will have frequent updates throughout the day on AlabamaWX.com

Category: Alabama's Weather, Severe Weather