After a calm but cooler day (compared to Saturday), we now await our next weather system that could be quite the doozy…
Above is the HRRR model, showing what radar might look like as we go through the remainder of this evening and overnight hours.
A few showers associated with a stationary frontal boundary to our south will be possible during the early to mid morning hours. These showers look to be mostly light and won’t pose any real issues to the area, although a rumble of thunder or two can’t be ruled out.
Those showers look to clear out by mid to late morning, leaving us mainly dry through lunchtime ahead of what looks to be an active afternoon.
As we work our way into the afternoon hours, the atmosphere looks to destabilize as a low pressure system moves across the area, setting the stage for some strong thunderstorms to develop.
The Storm Prediction Center has placed southwestern areas of the Upper Cumberland from Carthage over to Cookeville, down into Smithville and Spara in the ‘Enhanced Risk’ (3 out of 5) category of seeing severe weather tomorrow afternoon and evening.
Farther north and east, we have a Slight Risk (2 out of 5) of severe weather encompassing much of the remainder of the Upper Cumberland (Lafayette, Livingston, Crossville).
Byrdstown and Jamestown are in the Marginal Risk (1 out of 5) category.
For reference, here’s what the different risk categories mean:
In tomorrow’s case, all modes of severe weather look to be in play, including damaging winds, large hail and even the potential for a few tornadoes.
The tornado potential will be greatest for those south in the Enhanced Risk category, although an isolated tornado cannot be ruled out anywhere in the Upper Cumberland.
Unlike the severe storm setups we typically see in Middle Tennessee, we’re not necessarily looking at a ‘line’ of storms to move through that’s one and done.
Instead, scattered storms, including the possibility of a few discrete supercells (the big storm cells that have the potential to produce really large hail and sometimes violent tornadoes) look to form during the mid to late afternoon hours, perhaps lingering into the evening for areas up on the Plateau.
Because storms look to form individually, it’s near impossible to give an exact ‘when or where’ scenario, so the next best thing is a map (shown above) outlining the most favorable times for severe weather development. This looks to be from 3-7 p.m. for Lafayette, Hartsville, Carthage and east to Cookeville and Livingston. Those from Jamestown down to Crossville will see your windows perhaps around 5-9 p.m. (maybe not that late, but that timings allows some extra room in case a storm or two lingers around up on the Plateau).
Now, some things to note…
In their latest forecast discussion issued a short while ago, the National Weather Service pointed out that there are indications ‘capping’ could be in place during the early afternoon hours.
In non-meteorological terms, this basically means severe storm development will be limited as long as the cap is in place.
The cap will probably break at some point, but the longer it’s in place, the less strong storm develop will occur and the less severe storms will be.
If the cap breaks earlier in the afternoon, then all modes of severe weather will be very much in play, as many ingredients needed for severe weather development (including tornadoes) will be in place.
It’s something we’ll be watching closely for tomorrow, certainly.
Also the timing of our main severe weather threat will begin (at least for our western areas) around the time school is letting out, lasting through the afternoon and early evening, so outdoor activities will be impacted.
By late evening, our severe threat will have ended with a few showers possibly lingering into the overnight hours through Tuesday morning.
Stay weather aware tomorrow.
Have a plan in place and be ready to take action should your area be placed under a Severe Thunderstorm or Tornado Warning.
Also have a reliable way of receiving alerts, such as a NOAA Weather Radio or good weather alerts app (I personally like Weather Radio by WDT, available for both iOS and Android).
Mobile homes are not safe places to ride out severe weather, so if you live in a mobile home, it would be wise to make arrangements to hang out with friends or family members until the severe weather threat has ended.
Updates will be posted to our Facebook and Twitter pages throughout the day as necessary, including any watches or warnings that may be issued.
In addition to Upper Cumberland Weather, consult with multiple reliable weather sources throughout the day, including the National Weather Service in Nashville on social media and your favorite local TV meteorologists.