We expect an unusually high-end risk of severe storms for this time of year on Friday, Friday night and early Saturday morning: very high wind gusts, large hail, heavy rain, intense lightning and even a risk of brief tornadoes.
The afternoon outlook from the Storm Prediction Center shows a *SLIGHT* to *ENHANCED* risk of severe weather in North Alabama and Southern Middle Tennessee in the Friday/Saturday timeframe; that’s a statistical outlook. The enhanced risk is pushed a little east at 12:34am CDT Friday morning. The derecho we had on June 28th with wind gusts as high as 100 miles per hour came in a SLIGHT RISK as well (just for reference).
- Precise timing down to when a storm would hit a neighborhood cannot be determined yet; however, we do expect the first heavy storms of the day (Friday) to begin in Tennessee in the early afternoon and move south-southwest into North Alabama between 4 PM and 8 PM. This is more of a ‘chance’ than a certainty. The more widespread, significant wave blows in later Friday night.
- The ‘main’ wave that has the highest potential for severe storms likely comes in between 10 PM Friday and 5 AM Saturday.
WHAT WE EXPECT:
- High wind gusts: a ‘severe’ storm has to have wind gusts at 58 miles per hour or higher. Some model guidance suggests isolated 70-80 mile per hour gusts.
- Tornado risk: it’s low but not zero. You may see charts floating around on social media showing ‘STP’ (significant tornado parameter) that look scary; that modeled severe weather parameter is not extremely useful for this kind of weather pattern. Think of it this way: a crescent wrench is a great tool unless the job requires a Phillips head screwdriver.
- Flash flooding: a few areas may see more than 2-3” of rainfall Friday and Friday night. That could produce some localized flooding.
- Lightning: we know of at least four lightning strike victims in North Alabama this summer. We have seen house fires from lightning, trees damaged, and a lot of power outages from it. Lightning will be a danger from these storms, so stay indoors and be aware of the risks if lightning strikes your property.