A storm system will impact the Tennessee Valley on Saturday. A line of thunderstorms along a cold front will bring with it the potential for brief damaging winds Saturday afternoon and evening. There are still some uncertainties with this forecast since it is not a setup that screams severe weather. The risk is quite low for damaging thunderstorms, but low risk does not always mean low impact. If these storms develop, and they can, they can pack a punch and bring down trees and power lines.
Scattered to widespread showers will form ahead of the main line of storms. These showers are possible any time Saturday after about 6-7 AM. Winds can be gusty during the day, but the damaging wind threat will be at its highest from 4 PM to 7 PM across the Shoals, then from 7 PM to 10 PM around Huntsville and along I-65, then from 9 PM to 12 AM for Sand Mountain. A brief tornado can't be ruled out. It is possible the damaging storm threat does not materialize. It's also possible that it will materialize. It's best to be prepared for the worst. That means be weather aware Saturday afternoon and evening. Be ready to move to your severe weather safe place if dangerous weather threatens.
Why the uncertainty? Depending on how widespread the showers are ahead of the main line of storms, the showers may help to tame the atmosphere. If instability is limited, the main line of storms will not have energy to feed it. That will make it weaker. This is a relatively small scale occurrence that may not show its affect on the severe weather potential until Saturday. With new data tomorrow, Friday, and Saturday, we will be able to fine tune this forecast. For now realize severe storms are possible Saturday afternoon and evening, and you should be prepared.
Thursday will be quiet. We will warm from the high 40s in the morning to the high 70s in the afternoon, so you may still want a light jacket first thing in the morning. Friday will be even warmer.