A cold front will pass from west to east Tuesday afternoon in North Alabama. For areas further east, there will be additional time to warm and destabilize ahead of the cold front today. This is why the thunderstorm and severe threat doesn't begin until closer to I-65 because the Shoals will be unable to destabilize in time prior to the cold front passage. Sand Mountain is the farthest east and last to see the front, therefore has the most time to warm and destabilize, allowing for more fuel for thunderstorms. The greatest risk for Jackson and DeKalb Counties will be damaging straight-line winds but hail and even a brief tornado can't be ruled out Tuesday. The severe threat will end by late afternoon or early evening as the front moves into Georgia.
In the wake of today's cold front, highs Wednesday will be running about 10 degrees below average - only hitting the upper 60s. It's similarly cool Thursday, even more so Friday. Another cold front brings another round of rain and some storms Friday, but it will be gone in time for the weekend. While that's good news if you want sunshine, the warmth won't be back. Highs Saturday are forecast to be in the lower 60s!