Published: Tuesday August 4, 2026
By Meteorologist Mike Witcher | eastTNweather
Good Tuesday morning, East Tennessee!
August has officially settled into a classic summertime weather pattern. If yesterday felt familiar, expect more of the same today as an upper-level low continues to meander across the Southeast, bringing another round of afternoon showers and thunderstorms—mainly across the higher terrain.
Yesterday’s Weather Recap
Temperatures climbed into the low, mid, and upper 80s across the region Monday.
- Crossville: 80°
- Knoxville: 87°
Rainfall remained very hit-or-miss, with the majority of the activity focusing on the Cumberland Plateau, while portions of Blount and Monroe counties picked up nearly one-half inch of rainfall. Many communities, however, stayed completely dry.
That pattern continues today.
Another Round of Afternoon Storms
After a mild and muggy start this morning, scattered thunderstorms will begin developing during the afternoon.
The biggest change today is storm motion.
Thanks to the position of the upper-level low, storms will be moving from the south and southeast, rather than the more typical west-to-east direction.
That means:
- Storms will likely initiate over the Great Smoky Mountains and higher elevations.
- A few storms will also develop across portions of the Cumberland Plateau, although coverage should be lower than what we experienced yesterday.
- Some storms will drift into nearby valley locations during the afternoon and evening.
Overall coverage remains scattered, and many neighborhoods will stay dry.
Heavy Rain Threat Lower Today
One encouraging trend is that precipitable water (PWAT) values are lower today than they have been recently.
With less moisture available in the atmosphere, widespread tropical-like downpours are not expected.
That doesn’t eliminate the flooding threat entirely.
If one of today’s slow-moving storms repeatedly tracks over the same community, localized urban or small-stream flooding could still develop. However, the overall flood risk remains fairly low.
The Weather Prediction Center continues highlighting portions of East Tennessee for a localized flooding risk, mainly because isolated heavy rainfall is still possible.
Temperatures and Heat
Morning temperatures begin comfortably in the 60s and 70s before climbing into the upper 80s this afternoon.
Winds remain very light throughout the day.
Humidity, however, remains elevated enough to push heat index values into the low to mid 90s, making it feel noticeably warmer than the actual air temperature.
While heat stress isn’t extreme, it’s becoming increasingly important as schools resume across East Tennessee.
Watching the Wet Bulb Globe Temperature
As students return to:
- Football practice
- Band camp
- Marching rehearsals
- Outdoor athletics
the Wet Bulb Globe Temperature (WBGT) becomes one of the most important weather tools available.
Unlike the heat index alone, WBGT considers:
- Air temperature
- Humidity
- Wind speed
- Solar radiation
These are the values the TSSAA uses to determine when schools should increase water breaks, shorten practice periods, or modify outdoor activities.
Expect to see WBGT updates become a regular part of the forecast as we move through August.
The Rest of the Week
Rain chances stay elevated through Wednesday before decreasing slightly Thursday and Friday.
By the weekend, another disturbance diving south from the Great Lakes should increase shower and thunderstorm coverage once again.
The overall pattern remains very typical for August:
- Quiet mornings
- Afternoon heating
- Scattered terrain-driven thunderstorms
- Storms gradually weakening after sunset
Rainfall Favors Higher Terrain
Forecast rainfall over the next several days continues telling the same story.
The mountains and Cumberland Plateau remain favored for the greatest rainfall totals, while valley communities see much more scattered, hit-or-miss activity.
That’s exactly what you’d expect during a classic East Tennessee summer weather pattern.
Looking Ahead
High temperatures remain in the upper 80s today and Wednesday before climbing toward 90 degrees later this week and into the weekend.
With dew points staying elevated, heat index values will continue running in the mid to upper 90s each afternoon.
Meanwhile, the Climate Prediction Center continues favoring above-average temperatures heading deeper into August, suggesting this summertime pattern isn’t going anywhere anytime soon.
Great Boating Weather
Despite the daily storm chances, this remains a great week to enjoy East Tennessee’s lakes.
Morning hours continue to offer the best conditions, while afternoon boaters simply need to keep an eye on developing thunderstorms using the interactive radar.
Remember, lightning can develop quickly during the summer months, so always have a way to receive weather alerts while you’re on the water.
Bottom Line
- Typical August weather continues today.
- Scattered afternoon storms develop mainly over the mountains and Plateau.
- Storms move from the south and southeast today.
- Heavy rain is less likely thanks to lower atmospheric moisture.
- Heat index values climb into the low to mid 90s.
- Afternoon boating remains excellent—just watch for pop-up storms.
Be sure to download the FREE EastTNWeather App for interactive radar, lightning alerts, live severe weather coverage, and my daily “One Minute with Witcher” forecast to help get your day started.
Have a great Tuesday, and thanks for making eastTNweather part of your morning!
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