The NWS Storm Prediction Center maintains a Level 3 of 5 risk of severe storms for late this evening and overnight for about all of southern middle Tennessee and now clipping northern parts of Tishomingo County, MS and northern parts of Lauderdale County, AL. South of that, a standard Level 2 of 5 risk of severe storms remains in place across the rest of north Alabama and northeast Mississippi. Our main concern is still a complex of thunderstorms moving into the area during the late evening (roughly between 9-11pm for arrival) and continuing through the area on into the early morning hours (through 2-3am) of predawn Saturday morning. The primary threat with this thunderstorm complex will be damaging straight-line winds of 50-60 mph with isolated gusts up to 70 mph possible, but we also can’t completely rule out an isolated brief tornado or two… even though that threat is low. We may also have a low-end risk of embedded hail up to quarter or half dollar size with the storms, and there may be localized street flooding with the heavy rain as the storms move across. Overall, this is not a major severe storm threat for our immediate local area, but it is still one you need to pay attention to because there may be some severe thunderstorm warnings issued overnight, and we can’t rule out a stray tornado warning or two.
The images above are a timeline of the in-house Baron “Futurecast” high-resolution computer model. It shows the complex of thunderstorms arriving in our western and northwestern counties as early as the 9:00pm hour and then gradually shifting eastward across the area through around midnight or so and weakening with time, before more mostly non-severe storms redevelop behind it and shift east across the area from midnight through 4:00am.
The next set of images above are a timeline from the HRRR computer model. It has the thunderstorm complex arriving a little later, closer to 11:00pm. Other high resolution models agree with timing, and even previous runs of the Baron model mentioned a moment ago had timing closer to this. It’s possible the Baron model from a moment ago may be a couple of hours too fast with the initial arrival time. Regardless, the HRRR also shows the thunderstorm complex gradually shifting east and southeast across the area from 11:00pm on through 2:00-3:00am and weakening with time as it moves across the area.
In any scenario, it appears likely that the thunderstorm complex will be weakening with time as it moves into and across the viewing area tonight, but even as it is weakening, it can still produce areas of damaging straight-line winds and possibly a brief tornado or two.
It is important that you pay attention to the weather tonight, have multiple reliable ways of hearing warnings, and have your safety plan in place before the storms arrive. This is nothing for you to be afraid of, but it is something for you to respect and to be aware of. We will be staffed in the weather center overnight, ready to provide live coverage updates as conditions warrant while the storms move through!
