CLARKSVILLE, TN (CLARKSVILLE NOW) – With highs Thursday and Friday near 100, the Extreme Heat Warning from the National Weather Service has been extended through Friday at 8 p.m.

Dangerously hot conditions are expected, with heat index values up to 111 on Thursday, the NWS said.

Tuesday’s high reached 94 degrees at 4 p.m. at Clarksville Regional Airport, with a 104 heat index. Monday was much the same. Sunday hit just under 92, with a 103 index.

| MORE: What’s a heat index? Your guide to summer heat warnings

Overnight lows will remain warm, only falling into the mid- to upper 70s, the NWS said. Some relief has become available in Clarksville with the opening of several cooling shelters.

For Independence Day weekend, there’s a 30% chance of storms Friday, 50% Saturday, then 40% Sunday. Highs will remain in the mid-90s.

Clarksville forecast

Here’s the day-by-day outlook.

Tonight: Mostly clear, with a low around 77. Calm wind.

Thursday: A 30% chance of showers and thunderstorms, mainly after 5 p.m. Mostly sunny and hot, with a high near 98. Heat index values as high as 111. Calm wind becoming north northeast around 5 mph.

Thursday night: A 30% chance of showers and thunderstorms before 7 p.m. Partly cloudy, with a low around 76. Northwest wind around 5 mph becoming calm.

Friday: A 30% chance of showers and thunderstorms after 1 p.m. Sunny and hot, with a high near 97. Calm wind becoming east around 5 mph.

Friday night: A 20% chance of showers and thunderstorms before 1 a.m. Patchy fog after 5 a.m. Otherwise, partly cloudy, with a low around 74. Calm wind.

Independence Day: A 50% chance of showers and thunderstorms after 1 p.m. Sunny, with a high near 95. Calm wind becoming east around 5 mph.

Saturday night: A 30% chance of showers and thunderstorms before 1 a.m. Partly cloudy, with a low around 74. West northwest wind around 5 mph becoming calm.

Sunday: A 40% chance of showers and thunderstorms, mainly after 1 p.m. Mostly sunny, with a high near 95. Calm wind becoming west southwest around 5 mph in the afternoon.

Sunday night: A 20% chance of showers and thunderstorms before 1 a.m. Partly cloudy, with a low around 74.

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