Wednesday, July 15, 2026 — Knoxville woke up to mostly clear, muggy skies and low 70s at McGhee-Tyson this morning, and the sticky start is only the opening act. A hot afternoon is on tap with a high near 89°F and heat index readings pushing into the mid 90s, making it feel several degrees hotter than what the thermometer shows. Winds stay light, so heat and humidity, not any cooling breeze, will drive the story today.
Afternoon Heat And Humidity
According to the National Weather Service in Morristown, afternoon highs will top out near 89°F with heat index values up to 96°F today and as high as 101°F on Thursday. Dew points in the low 70s will keep the air feeling tropical through the afternoon, especially in valley and low-lying neighborhoods. If you have to be outside during the peak heat, take frequent breaks, drink plenty of water, and keep an eye on children, older adults, and pets.
Storm Chances Ramp Up Friday Through Sunday
Showers and isolated storms are possible this afternoon, mainly south of I-40, and again Thursday evening, but coverage jumps Friday into the weekend as a trough moves into the East. Friday currently carries about an 80% chance of showers and thunderstorms, Saturday looks even wetter with roughly a 90% chance, and Sunday stays unsettled with a near 60% chance of storms. Forecasters note that the Weather Prediction Center and the local office have highlighted a marginal risk of excessive rainfall for Friday and Saturday, so slow-moving storms could spark brief, localized flooding.
Plan Ahead
It is a good idea to have a backup plan for outdoor events on Friday and Saturday and to keep an eye on the radar if you will be on the road, since repeated downpours can push creeks up and make some streets impassable. For today and Thursday, the bigger issue is heat, so shade, water, and shorter stints outside are your best defenses. Updates will follow if any watches or warnings are issued.
For background on the developing setup, see our July 9 update stormy shuffle before the soggy weekend. Check the National Weather Service for the latest forecasts and any watches or warnings.
