Knoxville is starting Friday mostly clear and around 73 degrees, but the calm morning will give way to a hot, humid afternoon. Temperatures are expected to reach 93 degrees, with the heat index climbing as high as 103. Showers and thunderstorms may arrive after 2 p.m., adding a little thunder to an otherwise sunny day.
The chance of rain is about 40% Friday afternoon, with light west winds staying between 0 and 5 mph. According to the National Weather Service in Morristown, no watches, warnings or advisories are currently listed for Tennessee in the latest forecast package.
Storms Could Bring Brief Downpours
Any storms that develop Friday could drop between a tenth and a quarter-inch of rain, though isolated heavier pockets are possible. The overall severe-weather threat is low, but forecasters are watching for localized flooding and isolated damaging wind gusts, particularly across Northeast Tennessee and Southwest Virginia.
Storm chances taper after about 10 p.m., with mostly cloudy skies and an overnight low near 75. The combination of high humidity and limited wind means the evening may not feel much cooler, even after the sun goes down.
Weekend Heat Peaks Sunday
Saturday turns hotter, with a high near 95 and heat-index values as high as 106. A few showers could pop up during the morning, followed by a chance of thunderstorms around midday and early afternoon before skies trend mostly sunny again.
Sunday currently looks like the hottest and quietest day of the weekend, with sunny skies and a high near 97. The low will remain around 75 Sunday night, offering only modest relief before another hot Monday with a chance of afternoon thunderstorms.
Heat Sticks Around Through Thursday
Monday is also expected to reach about 97 degrees, with storms possible after 2 p.m. Temperatures ease slightly to 92 Tuesday, 93 Wednesday and 94 Thursday, but the forecast remains firmly in summer mode, with additional storm chances Tuesday and Thursday.
Heat-index values meeting heat-advisory criteria are expected across much of the Tennessee Valley from Saturday through Monday, although no advisory is listed yet. Anyone spending time outside should plan for water, shade and frequent breaks, and move indoors quickly if a thunderstorm warning is issued or heavy rain begins to flood roadways.
