On this page · 8 sections
What does the MIAA require?
Every school or district must pick and promote a way of monitoring the environment for heat, and follow the statewide policy for all sports. The policy follows modified American College of Sports Medicine guidance on three things: scheduling practice and competition at different heat and humidity levels, the ratio of activity to rest and hydration, and the level at which activity is modified, altered or cancelled.
A scientifically approved WBGT instrument must be used at each activity. Indoor events without climate control take an indoor reading; climate-controlled events do not need one. Practice is timed from when players report to the field until they leave, and a walk-through of up to an hour sits outside that clock, with no conditioning and no protective equipment.
The device
A scientifically approved WBGT instrument at each activity, indoors too when the space is not climate-controlled.
Practice and games
The bands cover practice and competition. Games can be played up to and including a WBGT of 86.0°F.
Cooling zone
Rest out of direct sunlight. Above 84, ice water and towels in the cooling zone and cold-water immersion tubs available.
Rest breaks
Unlimited water or electrolyte drinks, no activity, and helmets off for sports that use them.
The MIAA WBGT threshold table
Five bands, read in degrees Fahrenheit from the WBGT instrument: one table for the whole state, for practice and competition. The row colour follows the Flash alert scale your athletic trainers already see in the app.
| WBGT (°F) | Activity limit | Rest breaks | Equipment |
|---|---|---|---|
| Below 76 | Normal activities | Provide at least 3 separate rest breaks each hour for a minimum duration of 3 minutes each during workout | None listed |
| 76.1 – 81.0 | Use discretion for intense or prolonged exercise, and watch at-risk players carefully | Provide at least 3 separate rest breaks each hour for a minimum duration of 4 minutes each | None listed |
| 81.1 – 84.0 | Maximum activity time is 2 hours | For all sports: Provide at least 4 separate rest breaks each hour for a minimum of 4 minutes each | For equipment intensive sports: Players should be restricted to a helmet, shoulder pads, and shorts during activity; all protective equipment must be removed for conditioning activities |
| 84.1 – 86.0 | Maximum length of activity is 1 hour. There may be no conditioning activities | There must be 20 minutes of rest breaks provided during the hour of activity | No protective equipment may be worn during activity |
| Above 86.1 | No outdoor workouts. Cancel exercise, and delay activity until a cooler wet-bulb globe temperature reading occurs | — | — |
Source: MIAA Heat Modification Policy, August 18, 2021, amended September 1, 2022, as linked from the MIAA Sports Medicine page (miaa.net), verified 15 Oct 2026. Ranges as printed. The policy adds: "If equipment modifications are necessary, no games should occur for that sport." Interscholastic competition can take place up to and including a WBGT of 86.0°F.
Where does Flash fit?
Flash is a forecast for planning, not an on-site meter: MIAA compliance uses the reading from your WBGT instrument. Flash's 6-hour WBGT outlook tells you at 1 pm what the 4 pm reading is likely to be, so you can move practice instead of cancelling it.
Heat: plan, don't cancel
The outlook runs per field for every hour of the afternoon, against the five MIAA bands. Shift the start, swap the equipment plan or go indoors before the cars arrive.
Lightning: up to 60 minutes ahead
Strike-level prediction on a 1×1 km cell, refreshed every 2 minutes. Up to 99.6% lightning prediction accuracy on a one-hour window, measured against NLDN ground-truth strikes — method published.
Accuracy methodReturn to play: the all-clear timer
After the last strike inside your radius, Flash runs your policy's all-clear timer and logs it, so play resumes on evidence.
Weather Command Center
Flash Heat and WBGT prediction 6-hour WBGT outlook, heat index, air temperature and dew point per 1×1 km cell
What does a planning day look like?
Illustrative example · Not live weather — the readings are examples, the rules are the MIAA's
6:30 pm · The reading that decides the day
The band you land in sets the clock, the breaks and the pads.
Flash 6-hour WBGT outlook for the practice field: 80 by 3 pm, into 81.1–84.0 by 4 pm. The athletic director flags the football session.
Decision: run at 4 pm under the 2-hour cap with four 4-minute breaks an hour, or push to 6:30 pm. The AD pushes. The bus, the trainers and the parents hear now, not at 3:45.
On-site WBGT reading as players report: 79.6, the 76.1–81.0 band. Three 4-minute breaks per hour go on the plan, in a cooling zone out of direct sun.
Flash lightning alert: a strike is predicted inside the site radius within the next 60 minutes. The field clears.
Last strike inside the radius. Flash starts the all-clear timer.
All clear. Practice resumes; the alert log records who was warned, when, and when play returned.
What should the athletic director keep on file?
The MIAA policy has each school or district select and promote its own monitoring method. Keeping these together means a question from the MIAA, the district or a parent is answered from one folder.
- The monitoring method the school or district selected, and the WBGT instrument it uses.
- WBGT readings with times for each activity, indoors too where the space is not climate-controlled.
- The band each reading fell in and the decision it triggered: activity length, rest breaks, equipment, whether a game went ahead.
- The cooling-zone setup: shade, ice water and towels above 84, cold-water immersion tubs.
- The Flash alert log: lightning alerts, who was notified, the all-clear, and the 6-hour outlook the schedule decision was based on.
Which other states publish WBGT policies?
Every state page follows this template: verified thresholds, the reading cadence, what to keep on file, and where the WBGT forecast fits.
State by state
Same instrument, different bands — the WBGT forecast travels with you.
- Georgia (GHSA)
- Texas (UIL)
- Florida (FHSAA)
- Arizona (AIA)
- Arkansas (AAA)
- Colorado (CHSAA)
- Hawaii (HHSAA)
- Illinois (IHSA)
- Kansas (KSHSAA)
- Mississippi (MHSAA)
- Missouri (MSHSAA)
- Nevada (NIAA)
- New Hampshire (NHIAA)
- New Mexico (NMAA)
- North Carolina (NCHSAA)
- Ohio (OHSAA)
- West Virginia (WVSSAC)
- Oklahoma (OSSAA)
- Alabama (AHSAA)
- California (CIF)
- Connecticut (CIAC)
- Iowa (IHSAA / IGHSAU)
- Kentucky (KHSAA)
- Louisiana (LHSAA)
- Minnesota (MSHSL)
- Nebraska (NSAA)
- New Jersey (NJSIAA)
- New York (NYSPHSAA)
- South Carolina (SCHSL)
- South Dakota (SDHSAA)
- Utah (UHSAA)
- Vermont (VPA)
- Virginia (VHSL)
- Washington (WIAA)
- Wisconsin (WIAA)
Sources
- MIAA — Heat Modification Policy, August 18, 2021, amended September 1, 2022. Thresholds, instrument rule, rest breaks, cooling zones, definitions. Verified 15 Oct 2026.miaa.net/sites/default/files/2024-06/miaa-heat-modification-policy-081821-amended-9-1-22cb.pdf (opens in a new tab)
- MIAA — Sports Medicine page, miaa.net, which links the Heat Modification Policy as the current MIAA heat policy. Verified 15 Oct 2026.miaa.net/about-miaa/sports-medicine (opens in a new tab)
MIAA documents are published at miaa.net (opens in a new tab).
Frequently asked
No. The MIAA requires a scientifically approved WBGT instrument at each activity, and that reading decides the band. Flash's 6-hour outlook tells you where it is heading — a scheduling tool, not a compliance instrument.
The table covers practice and competition. The MIAA allows interscholastic competition up to and including a WBGT of 86.0°F, and says that if equipment modifications are necessary, no games should occur for that sport.
Only where the space is not climate-controlled. Then the WBGT reading is taken indoors; climate-controlled indoor events do not need one.
No. A walk-through lasts no more than an hour and sits outside the practice-time limit, but it may not include conditioning or weight-room work, and players may not wear protective equipment.