This week will reach a dangerously sweltering peak as the heat index pushes over 100 degrees, the National Weather Service is warning.

Central Indiana is under a heat advisory, with above-average high temperatures combined with oppressive humidity. Thursday's temperatures could be the hottest it's been all summer for the Indianapolis metro area, according to the NWS.

"The hottest temperatures of the year are expected over the next few days. This combined with dewpoints in the 70s will result in dangerous heat indices. Remember to stay hydrated, limit outdoor activities, and check up on family/friends frequently during this heat wave," the National Weather Service Indianapolis posted on X (formerly Twitter) early Wednesday.

The hottest temperatures of the year are expected over the next few days. This combined with dewpoints in the 70s will result in dangerous heat indices. Remember to stay hydrated, limit outdoor activities, and check up on family/friends frequently during this heat wave. #inwx pic.twitter.com/rGGUHx1XTb — NWS Indianapolis (@NWSIndianapolis) August 23, 2023

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Indiana heat advisories

The conditions this week contribute to heat indices (what the heat feels like even if the actual temperature is lower) of over 105 to 110 degrees Fahrenheit. Heat advisories are triggered at 105 degrees.

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“With heat that intense and with that much humidity, you know it's very, very easy to overheat if you're outside or doing work or exercising outside,” said meteorologist Matthew Eckhoff.

The advisory is currently through Thursday night. Friday is expected to be a little cooler, with a high of 92 and a potential drop in humidity.

Dangerous heat is expected through much of this week. A heat advisory is in effect with heat indices likely around 105F across much of central Indiana today. Remember to stay hydrated and limit time outdoors if possible. #inwx pic.twitter.com/RfSfAAqJMv — NWS Indianapolis (@NWSIndianapolis) August 21, 2023

Places to stay cool in Indiana weather

Eckhoff recommends drinking plenty of water, limiting outdoor activities, staying in the shade, and getting into air-conditioned buildings when possible to cope.

Family centers at Indianapolis parks are operating as cooling centers during normal hours. For center and splash pad locations, visit https://bit.ly/3NQQrQD.

☀ It's going to be HOT this week. As a reminder, if you need a place to cool down, our family centers are open during normal operating hours as cooling centers. Splash pads are also available as a way to cool off! To learn more, click here: https://t.co/IaPaeKtXl8 pic.twitter.com/imqs4iJswM — Indy Parks🌲 (@IndyParksandRec) August 21, 2023

Most Salvation Army corps community centers across the state also serve as cooling centers, open to the public during normal operating hours with air-conditioned seating areas, restrooms and drinking water is provided. Find a Salvation Army at SalvationArmyIndiana.org.

The Salvation Army in Shelbyville is providing free fans to residents meeting certain criteria, including those living in households with seniors or young children, but without functioning air conditioners. Call 317-398-7421 for details.

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Nighttime forecasts

Also, the National Weather Service said residents shouldn’t expect the night to bring much relief.

The low temperatures in the mid-to-upper-70s mean it'll be hot and humid throughout the nights, Eckhoff said.

“If you don't have air conditioning, that could really heat up the inside of your house. That kind of heat, even at night, is unsafe.”

National Weather Service forecast for Indianapolis

Wednesday: Mostly sunny and hot, with a high near 93. Heat index values as high as 105. Light southwest wind increasing to 5 to 9 mph in the morning.

Wednesday night: Partly cloudy, with a low around 76. Southwest wind 9 to 11 mph.

Thursday: Mostly sunny and hot, with a high near 96. Heat index values as high as 107. West southwest wind 11 to 13 mph, with gusts as high as 20 mph.

Thursday night: Partly cloudy, with a low around 77. Southwest wind around 14 mph, with gusts as high as 22 mph.

Friday: Mostly sunny and hot, with a high near 91. West wind 7 to 9 mph.

Friday night: Isolated showers and thunderstorms before 2am. Partly cloudy, with a low around 72. Chance of precipitation is 20%.

Saturday: Mostly sunny, with a high near 86.

Saturday night: Partly cloudy, with a low around 63.

Sunday: Mostly sunny, with a high near 79.

Sunday night: Partly cloudy, with a low around 59.

Monday: Sunny, with a high near 81.

Monday night: Mostly clear, with a low around 59.

Tuesday: Mostly sunny, with a high near 82.

This article originally appeared on Indianapolis Star: Indiana weather forecast expects extreme heat in Indianapolis, region