Excessive Heat Warning: Stifling Heat Continues its Grip on West Des Moines, Polk County

An unforgiving upper level ridge of high pressure continues to bear down on Polk County, bringing with it temperatures in the upper 90s real-feel temperatures in the triple digits for a third consecutive day Thursday and promising more of the same into the long Labor Day holiday weekend.

It will be Saturday at the earliest before the heat breaks, the National Weather Service said. An excessive heat warning remains in effect for Polk County until 7 p.m. Friday. Most of the rest of Iowa is under a heat advisory.

It will feel like a sauna Friday with temperatures that could soar to 100, a milestone not yet officially reached in an unusual late-summer heat wave. Heat index values of up to 105 to 110 degrees are possible, with warm overnight temperatures in the mid- to upper 70s that will allow little relief from the stifling daytime heat, weather officials said.

“The cumulative effect of several days of heat will take its toll, particularly on those without air conditioning or those spending time outside,” the weather service said in the excessive heat warning. “These cumulative heat effects are more likely to be enhanced in the Des Moines area due to the tendency for warmer temperatures in larger metro areas.”

Some relief is expected Saturday, but even then the temperatures will be in the mid-90s under mostly sunny skies. Sunday’s high is predicted around 88, with temperatures moderating to around 80 for a daytime high on Labor Day

The weather service said the prolonged combination of hot temperature and high humidity create a dangerous situation in which heat illnesses are likely. As a precaution, the weather service advises drinking plenty of fluids, remaining in air conditioning when possible and staying out of the sun.

Polk County is offering one overnight cooling shelter at the Zion Lutheran Church in Des Moines and several other locations around the county. Here’s a full list of daytime cooling shelters, which include the West Des Moines Public Library, Valley West Mall and Jordan Creek Town Center.

The Des Moines Area Regional Transit Authority is offering free bus service to the cooling shelters until the heat breaks.