Now what y'all gotta let it get so hot out here for?!?! We gotta talk to Ben Luna and tell him to turn off the oven. We're gonna be falling off the bone done by this afternoon! The National Weather Service offices between Nashville and Memphis have hoisted an Excessive Heat Warning for today into the early evening for Wayne, Lewis, and Hardin Counties in the Tennessee portion of our viewing area. The remainder of our viewing area across middle Tennessee, north Alabama, and northeast Mississippi remains under a Heat Advisory that will likely be extended daily for at least the next couple of days. Locations within the warning area are expected to have heat index values as high as 110 degrees or higher by this afternoon, and the advisory area is expected to have heat index values at or above 105 degrees later today.
For now, we are on the mild side early this Wednesday morning across the Tennessee Valley. Temperatures in our area are hanging out in the mid 70s. Radar is quiet across our local area, and even looking regionally, the closest showers and thunderstorms to our area this morning are in eastern areas of middle Tennessee down into north and east central Georgia, and these are moving away from our local area.
Skies stay mostly sunny to partly cloudy as we head through Wednesday. Temperatures begin climbing into the 90s by midday, and we look to top out in the mid to upper 90s as we head into the late afternoon. Reliable high resolution model data is keeping us dry through the day today, and that looks right to us so far. As we head into the overnight, clouds increase with time as a frontal boundary approaches the area. As we head into the early morning hours before daybreak, we may see a few isolated showers or storms developing over the area before they shift south of our region by the late morning to midday hours of Thursday. Notice though that these will be isolated to widely scattered, and unfortunately, not everyone will get rain.
A stray shower or storm can't be completely ruled out into the afternoon or early evening hours of Thursday as the front gradually shifts through, but morning activity shifting south of us by midday looks to organize into a thunderstorm complex to our south, and that will likely steal energy and focus away from the front for any chance of more substantial redevelopment later in the day. From there, we look to go dry from Friday into the weekend as the front shifts to our south, drier air moves in, and an upper-level heat ridge builds in overhead. That means temperatures warming through the remainder of the week and weekend, with highs near 100 Sunday into Monday, but the good news is that drier air moving in will lower dewpoints and keep heat index values Friday through at least Sunday from getting too extreme, in the lower 100s... compared to maybe a 110+ range that would otherwise be possible if we had muggy air hanging around.