Wednesday’s Storms: What to Expect

11:26 AM Update
A Severe Thunderstorm Watch is in effect until 7pm for most of the Tennessee Valley:

WATCH

 

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The Storm Prediction Center’s Day One Outlook has all of the Tennessee Valley, Central Alabama, and Middle Tennessee in a SLIGHT RISK through this evening. Storms could potentially produce “all modes of severe weather;” that means strong winds, hail, and a low-end threat of tornadoes. This is not the same kind of threat we faced back on April 28th!

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Thunderstorms have already been rumbling through the region this morning; new ones develop by midday and early afternoon. One big limiting factor for severe weather in North Alabama and Tennessee will be storms to our south; those heavier thunderstorms could help cut off the moisture supply and disrupt the low-level wind fields enough to lessen the risk up this way. This is the HRRR model’s output from Noon to 10 PM; watch those heavy storms to the south:

There is always uncertainty with thunderstorms. They occur on a smaller scale than our forecast models can “see” with great detail; in other words, we know they’re going to be out there, but we cannot pinpoint a location for them hours in advance.

The Timeline: Expect the breeze to increase from the south to around 10 to 20 miles per hour this afternoon and evening; that along with a dynamic storm system west of us helps fire some more heavy downpours with lightning and thunder through early afternoon. The swirl on the water vapor image shows where the main upper-air system is this morning:

Morning Water Vapor Loop showing the strong upper-air portion of this storm system heading toward Alabama & Tennessee

Morning Water Vapor Loop showing the strong upper-air portion of this storm system heading toward Alabama & Tennessee

The strongest thunderstorms will be likely in the afternoon and evening; strong to severe storms begin around 2 PM in The Shoals and slowly work east through the evening hours crossing I-65 between 6 and 8 PM. They shift on into Northeast Alabama by 10 PM.

HOWEVER – storms developing ahead of the main line could impact areas east of I-65 as early as 7 to 8 PM. Anything that gets out in front of this will have to be watched very closely.

Stay Informed! WHNT News 19 offers and recommends several ways to stay up-to-date on the weather even when you’re on the go. We’ll be watching this for you, and if there’s something significant going on, you’ll know it as long as you stay plugged in with us through the evening:

WHNT.com’s Maps & Radar Page
Mobile Applications
Baron Saf-T-Net

-Jason
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1 Comment

  • Jason Simpson

    Bobbie…there’s a small chance through this evening for all counties in North Alabama. The watch is just west of you right now, but it may be extended east if that threat materializes.

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