We're at the midday hour, and it's already getting ugly pretty much everywhere. Temperatures are already in the low to mid 90s for almost all of us, with heat index values already over 100. A few locations are already in the 105-110+ range with the heat index, and we have several more hours to go. The potential for heat exhaustion is already high to extreme, and this will only continue to go downhill through the afternoon. This type of heat isn't something new or unheard of. We see this a few times almost every year. However, that doesn't make it any less serious, and you have to take care of yourself on days like today... staying hydrated, taking breaks as often as possible, checking on the elderly and outdoor animals, and other common sense things.
We had a few showers on radar over western Tennessee earlier this morning. Those showers were forming above a capping inversion, and for the most part, none of it was reaching the ground. We don't really expect any heat relief in terms of rain today, and even the cloud cover isn't doing all that much to help out. Afternoon highs today look to climb into the mid to upper 90s areawide, with heat index values between 105 and 110 degrees.
Temperatures only fall back toward the mid/upper 80s by 8-9pm, and then we don't make it out of the mid to upper 70s overnight. Not only does this give us a high place as a starting point for the temps tomorrow morning, but that means there's not as much "recovery time" overnight, especially for those folks that don't have air conditioning. Our high resolution Futurecast model is showing some thunderstorm activity over northern Alabama tomorrow afternoon, mainly south of the Tennessee River, working in from the east. It remains to be seen if this will be the case. There is some model disagreement. However, this is a sign that rain chances will be working back into the forecast this week.
Unless models just aren't handling any potential thunderstorm complexes that well (and those are likely to stay to our north and east), our rain chances will be hit and miss this week, but they will start to return. What will also carry through the rest of the week is the heat. While it peaks in intensity today, heat index values look to remain near 105 degrees for tomorrow, if not a touch higher, and near or over 100 degrees through Friday. We see a bit of relief as we head into the weekend. A slightly drier air mass works into the area. Afternoon highs will still be in the upper 80s to near 90 degrees, but the lower humidity will allow those temperatures to be a lot more tolerable.