High school football preseason games are set to kick off across Florida this week provided the state's record-breaking heat wave eases.

The Florida High School Athletic Association sent a message this week to its members reminding them about the need to adhere to Policy 41, which outlines the temperature guidelines for when outdoor activities can proceed as normal.

If it’s too warm to safely play, football games could be canceled or postponed. More likely, schools would have to delay the starts until temperatures cooled.

In Southwest Florida, the Lee County School District moved back the start times for regular season high school football games from 7 to 7:30 p.m. in an effort to avoid heat-related delays as well as limit lightning stoppages. Rules state a contest cannot begin more than two hours after its scheduled start time.

But even that may not be late enough.

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"Who knows, we may be starting even later," Ida Baker High School athletic director Dan Butler said. "I mean, it’s 8 o’clock and it’s still 90 degrees outside."

Excessive heat advisories and warnings have been commonplace across the state this summer. Through Monday, there have been 117 days so far this year where the high temperature in Fort Myers has been 90 degrees or higher. That’s 51 days more than the typical number through mid-August.

Since the passage of the Zachary Martin Act in 2020, the FHSAA requires its members to monitor heat stress and modify outdoor practices and games based on Wet Bulb Global Temperature (WBGT) guidelines. The law is named after former Riverdale High School football player Zach Martin-Polsenberg, who died 11 days after suffering heat stroke following a workout at the school in June 2017.

High school athletic trainers monitor the wet bulb temperature using a handheld device and communicate to coaches and athletic directors when the readings are unsafe for outdoor athletic activities. The device measures heat stress in direct sunlight, taking into account temperature, humidity, wind speed, sun angle and cloud cover. The wet bulb temperature is lower than the air temperature except at 100% relative humidity when it is the same.  

One of those trainers is Patrick Gorrell, who is in his fourth year at Riverdale. Each day he sends wet bulb temperature readings to the school’s coaches at 1:15 p.m., 15 minutes before the end of the school day, so coaches have time to adjust their practice schedules if necessary.

At 82 degrees or below on the wet bulb, athletic practices and games can be held without restrictions. Up to 86.9 degrees, they can proceed with discretion. At 87 degrees or higher, practice times are limited, rest breaks are increased and football players are instructed to remove some protective equipment, which would result in game delays. A wet bulb temperature above 92 degrees means all outdoor activities are suspended and cannot resume until temperatures cool.  

"For the past while now it’s been above 92 just about every afternoon and that’s what’s been difficult for having outside practices," said Gorrell, who added he’s recorded wet bulb temperatures as high as 98 degrees this summer. "Hearing from people in other parts of Florida, it’s been pretty much the same everywhere."

Lee and Collier County athletic directors were polled on how many practices their football teams have held outside due to the heat since they could start July 31 and most said between one to five. Many have moved practices to before school to get outside safely.

Gorrell said that for high school football games the home school’s athletic trainer is responsible for taking the wet bulb temperature readings and communicating them to the teams and referees.

The heat is not just a Southwest Florida issue. John Stilanous, the coordinator over seven Clay County public high schools outside of Jacksonville, said his school district will treat the heat measurements similar to a lightning delay.

"We would exercise caution and consider delaying the kickoff and/or pregame warmups until the wet bulb temperature decreases to an acceptable and safe range," Stilanous wrote in an email. "This aligns with our commitment to ensuring the optimal conditions for our students' participation."

Collier County’s district athletic coordinator Mark Rosenbalm said after evaluating the wet bulb readings at the schools for the past couple of weeks, the district decided to push this week’s preseason football games back to 7:30 p.m. Decisions about the start times for games beyond this week will be based on projected conditions.

"Our stance is that student-athlete safety is of the utmost importance," he said.

Rosenbalm said some of Collier’s football teams have pushed their afterschool practices later into the evening in order to escape the worst of the heat.

"I know coaches get frustrated when their practice plan doesn’t go according to what they like it to but they’ve all adapted," he said.