Areas of rain will track across the Tennessee Valley on Friday. That rain will be breaking up, so some of us will stay dry, but rain will be around.
A cold front stretching from the eastern Great Lakes through Indiana and Illinois into Missouri on Thursday afternoon is tracking slowly east/southeastward and toward the Tennessee Valley. Showers and thunderstorms have formed in a line along the cold front, and the rain will accompany the cold front as it tracks across the Valley. The air behind the cold front will not be much colder, but it will be drier. Lower humidity will return for the weekend and keep showers at a minimum.
The rain is most likely to fall across the Shoals. Since the rain will be breaking up, widespread rain is less likely the farther east you are. Spotty showers with some areas staying dry will be more common along and east of I-65, including Huntsville, Madison, and Sand Mountain. Even with the rain breaking up, the chance for rain will start increasing across the Shoals between 9 AM and 11 AM, then along I-65 east through Huntsville and Fayetteville between 11 AM and 1 PM, then across Sand Mountain between noon and 2 PM.
Rainy areas will mean slippery spots on the roads. Some spotty lightning and thunder are possible, but severe thunderstorms are not likely. The morning drive and evening drive will be mostly dry. The lunch drive may require the windshield wipers and umbrellas.