Oklahoma sees a surge in heat-related health emergencies.

Ambulance crews in Oklahoma’s largest cities are grappling with a surge in heat-related health emergencies as daily highs continue to top 100 degrees across much of the state.

In Tulsa, Emergency Medical Services Authority, the state’s largest ambulance provider, has responded to 84 heat-related illness calls and taken 55 patients to hospitals since July 1, when the third heat alert of the year was issued for the city. In Oklahoma City, since a heat alert on July 7, the agency has responded to 59 calls, with 42 patients taken to hospitals.

Nearly all of the hospitalized patients in both cities were treated for heat exhaustion, heat stroke or heat-induced illnesses related to underlying medical conditions.

“We’re trending about six weeks ahead in terms of heat-related call volume than we have in years past,” said Adam Paluka, a spokesman for the authority, which is a public trust of the Tulsa and Oklahoma City governments.

Little relief is in sight, with temperatures forecast to climb as high as 112 degrees this week in Oklahoma City as a punishing heat wave brings some of the hottest temperatures so far this summer to much of the Central Plains and Texas.

In Tulsa, which has not had measurable rainfall since June 10, the ambulance authority had already received two heat-related emergency calls by 9:30 a.m. Monday morning, with one person taken to the hospital.

“This isn’t our first rodeo,” Mr. Paluka said, citing the agency’s experience in dealing with weather emergencies. “But it is probably the most intense prolonged heat that we’ve seen since 2011 or 2012.”

Staffing shortages and rising fuel prices have added to this summer’s challenges. Mr. Paluka said the authority was encouraging medics to leave air-conditioning on in their ambulances, for the comfort of themselves and patients, regardless of fuel prices.

The ambulance crews are regularly responding to heat-related 911 calls related to outdoor alcohol consumption, which can leave people severely dehydrated during a heat wave, Mr. Paluka said.

“People think that heat-related illnesses happen to old people with a pacemaker,” Mr. Paluka said. “But the most common demographic for our responses are adults between 20 and 40 years old.”