Here is the latest from the National Weather Service in Huntsville regarding the severe weather threat for the overnight hours this evening.

All of north Alabama is under an Enhanced Risk (Level 3 of 5) for severe weather. 
The primary threats are large hail, damaging winds, and tornadoes, though confidence in the tornado threat is low.
There is also a threat of localized flash flooding.

For the Huntsville Utilities service area, the most likely timing window for this system is 2am to 6am, though it could arrive as early as midnight and depart as late as 8am. 

We are closely monitoring the weather and have crews standing by to respond to service issues.

Remember:
If you see a downed power line, do not approach it or attempt to drive over it.
Do not attempt to remove limbs, trees, or debris from power lines.
Report either of these situations to 256-53-LIGHT (256-535-4448). This is also the number for reporting power outages.

Customers are advised to monitor local media and the National Weather Service website (weather.gov/hun) for updates.