The heat continues across the Tennessee Valley on this Thursday with an Excessive Heat Warning and Heat Advisory continuing across the area through early Friday evening. Where it hasn't rained this afternoon, temperatures are as warm as the mid to upper 90s, with heat index values in the 105-112 degree range. However, there are a few rain-cooled areas that are hanging out as "cool" as the 80s this afternoon.
Showers and thunderstorms are once again dotting the landscape across the area. Frequent cloud-to-ground lightning has been a big problem with the storms today. Otherwise, locally heavy rainfall and occasionally gusty winds have also been common.
The Storm Prediction Center actually has our area outlooked in low-end severe weather risks for today, Friday, and Saturday. The main concern each day is that one or two storms may have gusty straight-line winds that may be intense enough to prompt a few severe thunderstorm warnings. The overall risk of severe weather for any of these days, however, is low.
Afternoon showers from today will fade away during the mid evening as we begin to lose daytime heating. After that, we become partly cloudy with overnight lows in the mid 70s. We do this all over again for Friday, but daytime storms may not be quite as numerous. Aside from hit-and-miss storms, we will be partly cloudy and hot once again with daytime highs well up into the 90s and heat index values over 105 degrees. There is some potential for evening and overnight showers and storms to become a bit more numerous, but models are not in agreement on the exact placement and coverage of that overnight activity... and that will be dictated by how it develops upstream during the day tomorrow and is something we just can't have a good handle on this far out. For this reason, we will maintain the mention of scattered showers and thunderstorms during the evening and overnight hours as well.
Current indications still suggest a good chance of widespread showers and thunderstorms as a front moves through the area on Saturday. Models disagree on the exact timing, with some models focusing on morning timing and others focusing on the afternoon and evening. Some of that will depend on how Friday night storms behave. Locally heavy rainfall and gusty winds will be possible with these storms as they move through. A few isolated storms may persist into Sunday, but that front will be bringing in drier and very slightly cooler air as we head Sunday into early next week.
Any of this rain is definitely welcome news. The latest update to the Drought Monitor shows expanding drought conditions across southern Tennessee and northern Alabama, and severe drought conditions developing from Hardin and McNairy Counties in Mississippi, southward through northeast Mississippi.