East Tennessee Weather: Sizzling Heat Wave Grips the Week with Weekend Rain Relief

I mean… it’s summer, and it’s supposed to be hot, right? But this heat wave in East Tennessee is next-level, sticking around all week long!
On this Monday, June 23, 2025, at 7:24 AM EDT, we’re diving into sweltering conditions with highs in the mid to upper 90s and heat indices flirting with the low 100s. The National Weather Service hints at likely HEAT ADVISORIES for Tuesday and Wednesday, and weekend rain offers some relief. From the bustling streets of Knoxville to the misty trails of the Great Smoky Mountains and the vibrant riverfront of Chattanooga, the EastTNweather platform, led by meteorologist Mike Witcher, delivers hyper-local updates via its app, website, YouTube, Roku, Amazon Fire, and Apple TV to keep you weather-ready.

Monday: A Sweltering Start with Isolated Afternoon Storms
Monday kicks off with an already warm morning, with temperatures in the 70s across East Tennessee, a step up from the cooler 60s we saw earlier this month. High humidity, with dew points in the low 70s, makes the air feel sticky from the get-go. By lunchtime, temperatures soar to near 90°F, with afternoon highs climbing to the mid to upper 90s, about 12-15 degrees above the seasonal average of 81°F. The heat index, factoring in the humidity, pushes into the low 100s, particularly in valley locations like Knoxville, Chattanooga, and Cleveland. The Cumberland Plateau and Smoky Mountains feel slightly less oppressive, with heat indices around 95-100°F.

Diurnally driven by daytime heat and terrain, isolated afternoon thunderstorms are possible, primarily along the Cumberland Plateau and in the Smoky Mountains near Gatlinburg or Cherokee. These storms will be brief, producing less than 0.25 inches of rain, keeping most areas dry. The EastTNweather app is your essential tool for tracking these pop-up storms, with its Interactive Radar offering past, current, and two-hour future projections. Plan water-based activities like kayaking on the Tennessee River in Chattanooga, swimming in the Smoky Mountains’ streams, or boating on Fort Loudoun Lake in Knoxville, but shift to indoor options like the Tennessee Aquarium in Chattanooga or the East Tennessee History Center in Knoxville during 2-6 PM storm risks. Check the app for storm and heat alerts, and stay hydrated!

Tuesday-Wednesday: Peak Heat with Likely HEAT ADVISORIES
Tuesday and Wednesday mark the hottest days of the week, with the National Weather Service signaling likely HEAT ADVISORIES due to highs in the mid to upper 90s and heat indices nearing or exceeding 105°F, the threshold for advisories. Dew points in the low 70s amplify the muggy feel, making conditions feel oppressive across East Tennessee, including the Cumberland Plateau and Smoky Mountains. Valley areas like Knoxville, Chattanooga, and Athens will see heat indices of 100-105°F, while Morristown and the Tri-Cities north of I-40 may hover slightly lower, around 95-100°F. The UV index remains extremely high, increasing sunburn risks for outdoor activities in Pigeon Forge or Cleveland.

Isolated afternoon storms remain possible, driven by heat and terrain, with the Cumberland Plateau and Smoky Mountains most likely to see brief showers or thunderstorms (under 0.25 inches). The EastTNweather app’s long-range forecasts will confirm these scorching days, with alerts for heat advisories. Schedule water activities early in the day, like swimming in Sevierville or visiting splash pads in Chattanooga, and plan indoor tasks during peak heat (10 AM-4 PM). Check on neighbors, especially the elderly, in humid areas like Cleveland or Chattanooga. The platform’s streaming updates on YouTube, Roku, Amazon Fire, and Apple TV provide heat safety tips, ensuring flexibility for plans in Sevierville or the Cumberland Plateau. This is peak summer heat—stay cool and vigilant!

Thursday: The Heat Wave Holds, Storms Persist
Thursday continues the heat wave, with highs in the mid to upper 90s and heat indices near 100-105°F, potentially still under a HEAT ADVISORY depending on humidity. Dew points in the low 70s keep the air thick, with isolated afternoon storms possible in the Smoky Mountains and Cumberland Plateau, producing minimal rainfall (under 0.25 inches). North of I-40, including Knoxville and the Tri-Cities, stays mostly dry but swelteringly hot. The EastTNweather app’s Interactive Radar will track these storms, with push notifications for heat or storm alerts. Plan morning hikes in Cades Cove or markets in Jonesborough, but shift to indoor activities like the Knoxville Zoo during afternoon heat or storm risks. The platform’s streaming updates ensure you stay prepared for another hot day.

Friday-Sunday: Staying Hot with Increased Chances For Rain
Friday through Sunday sees a slight shift as the strong ridge of high pressure begins to break down and move to the Eastern Seaboard, while an area of low pressure spins up near Florida. This brings elevated rain chances, with better coverage of showers and storms, though not a washout. Rainfall totals from Friday through Sunday will likely be 0.5 inches or less, providing some much-needed relief to drying soils. Highs remain in the upper 80s to low 90s, with dew points in the low 70s keeping the heat index around 95-100°F, a bit cooler than midweek but still warm and humid. South of I-40, including Chattanooga, Cleveland, and Athens, sees the most rain, while north of I-40, like Morristown and the Tri-Cities, gets spottier showers.

The EastTNweather app’s forecasts will track these weekend storms, with alerts for localized flood risks in areas like Sevierville or Kingston near the Little Pigeon or Clinch Rivers. Don’t cancel outdoor plans—barbecues in Knoxville, festivals in Pigeon Forge, or kayaking in Chattanooga are still viable—but check the app for storm-free windows, especially mornings or early evenings. The high UV index persists, so apply high-SPF sunscreen for outdoor events. The platform’s streaming updates ensure you stay flexible, keeping your weekend plans vibrant and safe.

Rainfall Outlook: Light to Moderate at Times
Over the next seven days, rainfall totals will range from 0.5-1 inch across East Tennessee, with most rain falling Friday through Sunday. South of I-40, including Chattanooga, Cleveland, and Athens, may see closer to 0.5-1 inch, while north of I-40, like Knoxville and the Tri-Cities, expects 0.25-0.5 inches. Isolated storms Monday through Thursday will contribute minimal amounts (under 0.25 inches daily). Areas hit by repeated storms could see slightly higher totals, raising localized flood concerns in urban areas like Knoxville’s downtown or near rivers like the Hiwassee in Cleveland. The EastTNweather app’s Interactive Radar and flood alerts are vital for monitoring rain, especially in flood-prone areas. Check the app daily to stay ahead of potential flooding.

Heat Safety Tips for East Tennessee
With highs in the mid to upper 90s and heat indices nearing 105°F, heat safety is critical, especially with likely HEAT ADVISORIES Tuesday and Wednesday. The high UV index increases sunburn risks, making precautions essential. Here are key tips to keep you, your family, and your neighbors safe:

• Stay Hydrated: Drink water regularly, even if not thirsty, and avoid alcohol or sugary drinks during outdoor activities in Knoxville or Chattanooga to prevent dehydration.
• Protect Against Sunburn: Apply high-SPF sunscreen (30+), reapplying every two hours, and wear hats, sunglasses, or UV-protective clothing for lake trips in Cleveland or hikes in the Smoky Mountains.
• Take Breaks: If working outdoors in Sevierville or Athens, take frequent shade breaks and avoid strenuous activity from 10 AM to 4 PM, when heat peaks.
• Check on Vulnerable Neighbors: Visit elderly or at-risk neighbors in Chattanooga or Cleveland, ensuring they have access to air conditioning or cooling centers during the 100-105°F heat index.
• Know Heat Illness Signs: Watch for dizziness, nausea, or rapid heartbeat, signaling heat exhaustion or heat stroke. Seek immediate medical help if symptoms appear.
• Plan Water-Based Fun: Beat the heat with swimming at Ijams Nature Center in Knoxville, kayaking in Chattanooga, or visiting pools in Pigeon Forge. Check the EastTNweather app for storm-free times.