The low temperature was 75 degrees on Wednesday, matching the record set 82 years ago on June 25, 1943, according to the National Weather Service.
Dayton has set new record warm lows on Tuesday and Sunday as a heat wave lingered in Southwest Ohio.
The low temperature on Tuesday was 74 degrees, breaking the record of 73 degrees set in 1914.
Sunday’s low of 77 degrees beat the 37-year-old record of 74 degrees previously recorded in 1988.
On Monday, the low temperature of 73 degrees matched the record set in 1944.
Heat and humidity continue today. Isolated damaging winds and flooding are also possible. pic.twitter.com/mdpNVoyPQG
— NWS Wilmington OH (@NWSILN) June 26, 2025
A heat advisory was initially scheduled to end Wednesday evening but was extended through 8 p.m. Friday as hot temperatures and high humidity linger in the region.
The excessive heat paired with warm overnight temperatures could result in heat-related illnesses. People should drink plenty of fluids, stay out of the sun and rest in air-conditioned rooms, according to the NWS.
Public Health - Dayton & Montgomery County reminded people to watch for signs of heat stroke and heat exhaustion.
Symptoms of heat exhaustion include:
- Heavy sweating
- Weakness
- Skin cold, pale and clammy
- Nausea or vomiting
- Fainting
Those showing signs of heat exhaustion should move to a cooler location, lie down and sip water. Try to loosen clothes or apply cool, wet clothes to as much of the body as possible.
If a person is vomiting or symptoms get worse or last more than an hour, seek medical care.
Signs of heat stroke are
- High body temperature (more than 103 degrees)
- Hot, red, dry or moist skin
- Rapid and strong pulse
- Confusion
- Possible unconsciousness
Heat stroke is a medical emergency and 911 should be called immediately. Move them to a cooler place and try to reduce their body temperature with cool cloths or a bath.
Do not give fluids to a person with heat stroke.
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