MINNEAPOLIS - Minnesotans are dealing with stifling heat and high humidity as they try to celebrate the July Fourth holiday safely.

The KARE 11 Weather Department says that temperatures reached 100 degrees on Wednesday. Humid conditions made it feel even hotter.

Twin Cities' hospitals have seen an increase in the number of patients being treated for heat-related conditions.

Regions Hospital emergency room physician Gary Mayeux says there's been a 15 to 20 percent increase in heat exhaustion cases in the last week. He says ER personnel are also treating more cases of assault injuries, often associated with increased irritability and exacerbated by alcohol.

Regions and Hennepin County Medical Center say they've treated at least 16 patients with heat-related illnesses this week.

The National Weather Service issued an excessive heat warning for the southern half of Minnesota through Thursday.

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