A major, dynamic storm system embedded in the jet stream moves east from the Plains Saturday. Warm, humid air moving north ahead of it destabilizes the atmosphere and provides fuel for some heavy thunderstorms Saturday, Saturday night and Sunday starting in Texas, Oklahoma, Arkansas and Missouri, moving east through Alabama and Tennessee Saturday evening, and passing through East Alabama, Georgia, northern Florida and the Carolinas on Sunday.
There are still some questions about the ‘quality’ of the fuel we’ll have for this event; even a slightly unstable atmosphere will give us storms, but the more unstable it becomes, the more intense those storms could become.
As of Wednesday, it looks like the timeline for heavy rain and severe storms in the Tennessee Valley region comes from around 1-2 PM in The Shoals to as late as 10 PM to midnight near Sand Mountain, Lookout Mountain and the Coosa River Valley. That’s a very wide window; we’ll narrow it down more over the next few days as the specific details come into view.
The bottom line is that you should be prepared for rain, wind, and some severe storms in the region Saturday afternoon and evening.
- What’s possible? Strong wind gusts over 60 miles per hour, torrential rainfall, and there is at least some risk of tornadoes in Alabama and Tennessee.
- What are we waiting to determine/expecting to change? The rain and storms are definitely coming; the ‘fuel’ for the storms is questionable, so that fuel (instability) will have a large influence over the ultimate strength of the storms.