It appears a weak surface trough has formed in central Alabama, with pressures falling rapidly. This has actually increased the storm-relative helicity values somewhat in the past hour, with 400-600 in the area from Cullman to Tuscaloosa. This may be causing the intense rotation in the storm now in Cullman county.
Instability has changed little with CAPES still 500-1000 J/kg. Storms will continue until after sunrise, with a new tornado watch in effect until 10 am.
Most intense storm is the one near Holly Pond at 420 am. This storm will move into northern Blount county and also Marshall county. However, the main line of storms extends from Huntsville to Meridian, and another storm in that line, in southern Fayette county, is showing rotation and will move near Jasper, Oakman, and Parrish.
The line of storms may not move through BHM until 6 am or later, and individual storms within the line may still develop tornadoes. This could interfere with rush hour. Consider going to work late if storms have not cleared the area when you normally leave. A car is a bad place to be in a tornado, and the roads will be dangerous anyway if heavy rain is occurring right at 7 am.
