(From Todd Epp, Northern Plains News)
A dangerous and potentially historic early-summer heat wave is gripping much of South Dakota, northwest Iowa and southwest Minnesota.
The National Weather Service has issued an Extreme Heat Watch from Friday morning through Saturday evening, with heat index values forecast to reach as high as 108 degrees.
Clarification: Air Temperature vs. Heat Index
While actual air temperatures will be 90 or over, the combination of heat and humidity will make it feel much hotter, the NWS said.
The heat index, which measures how hot it feels to the human body by combining air temperature and humidity, is expected to reach up to 108. For example, an air temperature of 98 degrees with high humidity can feel like 110 or more. The heat index is especially important because it more accurately reflects the health risks posed by extreme heat, according to the National Weather Service.
The National Weather Service warns that heat-related illnesses increase significantly during extreme heat and high humidity events. Residents are advised to stay in air-conditioned buildings whenever possible, drink water frequently, avoid outdoor activity between 11 a.m. and 6 p.m., check on elderly neighbors, children and anyone without cooling, and never leave people or pets in closed vehicles.
Residents in South Dakota, Iowa and Minnesota can call 2-1-1 to find available public cooling spaces in their area.
A cold front may bring relief early next week, but through the weekend, the threat of heat-related illness remains high, the NWS said.
