Skip to content
Flash Weather
An empty floodlit high school football field at dusk with heat haze over the turf, the setting MSHSAA WBGT practice limits govern at Missouri schools

State heat policy · Missouri (MSHSAA) · Verified 15 Oct 2026

Missouri high school heat policy: MSHSAA WBGT thresholds, practice limits, and how to plan around them

The MSHSAA Heat Modification Policy sets five WBGT bands, printed separately for high school and middle school, that decide how long practice runs, how often players rest and what football players wear. Here are the bands as the MSHSAA prints them, what each district's own procedure must cover, and how a 6-hour WBGT outlook lets you move practice instead of cancelling it.

Flash Meteorology Desk · Checked against the MSHSAA WBGT Heat Modification Policy (mshsaa.org) · Updated 15 Oct 2026 · 7 min read

WBGT outlook · Field B · 6 hours

12:58

87.082921 pm2 pm3 pm4 pm5 pm6 pm
  • 4 pm · 88.1 — in 87.0–89.9
  • Under 87.0 after 5:20

Move practice to 5:30 — the on-site reading stays the compliance record.

Illustrative example · Not live weather
On this page · 8 sections

What does the MSHSAA require?

Schools must follow the statewide policy for practices and voluntary conditioning workouts in all sports, summer included, and each head coach signs it at the start of every season. It follows modified American College of Sports Medicine and National Athletic Trainers’ Association guidance on when practice is scheduled, how much time goes to rest and hydration, and the level at which practice ends. Middle school athletes get their own, lower bands.

A scientifically approved WBGT instrument must be used at each practice when the temperature is above 80°F, with readings every hour starting 30 minutes before practice or the event. Each school district writes its own procedure covering site-specific readings (equipment-laden sports first), when readings are taken, the modifications, who takes and records readings, how staff are told, and an exertional heat illness emergency action plan.

  • Reading cadence

    Above 80°F: first reading 30 minutes before practice or the event, then every hour, with a scientifically approved WBGT instrument.

  • District procedure

    Who performs and records readings, when, the modifications, communication, and a heat illness emergency action plan.

  • Cool zone

    Rest breaks out of direct sunlight, never combined with other activity, with unlimited access to hydration.

  • Practice clock

    Timed from arrival at the practice area until players leave it. A weather interruption stops the clock.

The MSHSAA WBGT threshold table

Five bands, read in degrees Fahrenheit from the WBGT instrument. High school and middle school have separate ranges; read across from your level. The row colour follows the Flash alert scale your athletic trainers already see in the app.

MSHSAA WBGT activity and rest-break guidelines for Missouri practice: five bands for high school, from under 82 to over 92, and middle school, from under 82 to over 90, with practice-length, rest-break and football-equipment rules
High schoolMiddle schoolActivity limitRest breaksFootball equipment
Under 82Under 82Normal Activities. Use discretion for intense or prolonged exerciseProvide at least 3 separate rest breaks each hour with a minimum duration of 3 minutes eachNone listed
82.1 – 86.982.1 – 83.9Use discretion for intense or prolonged exercise; watch at-risk players carefullyProvide separate rest breaks each hour for a minimum of 4 minutes duration eachNone listed
87.0 – 89.984.0 – 86.9Maximum practice time is 2 hours eachAll Sports: Provide at least 4 separate rest breaks each hour with a minimum duration of 4 minutes eachFootball: Players are restricted to helmet, shoulder pads, and shorts during practice
90.0 – 92.087.0 – 90.0Maximum practice time is 1 hour. Games/Contests: Implement additional official's timeouts for water breaks due to unusual heat/humidity/environmental conditions that may create risks for playersAll Sports: There must be 20 minutes of rest breaks distributed throughout the hour of practiceFootball: NO protective equipment may be worn during practice, and there may be NO conditioning activities
Over 92Over 90NO Outdoor Activity: Cancel or delay activity until a cooler WBGT is reached——

Source: MSHSAA Wet Bulb Globe Temperature - Heat Modification Policy, updated 6/25, as linked from the MSHSAA Sports Medicine page (mshsaa.org), verified 15 Oct 2026. Ranges as printed. If the WBGT rises into the third band during practice, football players may continue to work out in football pants without changing to shorts.

Where does Flash fit?

Flash is a forecast for planning, not an on-site meter: MSHSAA 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 bands for your level. 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 method

  • Return to play: the all-clear timer

    After the last strike inside your radius, Flash runs your policy's all-clear timer and logs it. The practice clock stops for the weather interruption, as the MSHSAA allows.

    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 MSHSAA's (high school)

An empty high school practice field under a hazy hot sun with a shade canopy and water coolers on the sideline, the setting for an MSHSAA WBGT planning day in Missouri

6:00 pm · The reading that decides the day

The band you land in sets the clock, the breaks and the pads.

  1. Flash 6-hour WBGT outlook for the practice field: 86 by 3 pm, into 87.0–89.9 by 4 pm. The athletic director flags the football session.

  2. 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.

  3. On-site WBGT reading 30 minutes before practice: 85.2, the 82.1–86.9 band. 4-minute breaks in the cool zone go on the plan and the designated staff member records the reading.

  4. Flash lightning alert: a strike is predicted inside the site radius within the next 60 minutes. The field clears and the practice clock stops.

  5. Last strike inside the radius. Flash starts the all-clear timer.

  6. All clear. Practice resumes for its remaining time; the alert log records who was warned, when, and when play returned.

What does the athletic director keep on file?

Each district's procedure must identify who performs and records WBGT readings. Keep these together so a question from the MSHSAA, the district or a parent is answered from one folder.

  • The statewide policy signed by each head coach at the start of the season.
  • The district's WBGT procedure: site-specific readings, when they are taken, modifications, who records them and how staff are told.
  • WBGT readings with times — 30 minutes before practice, then every hour — and the decision each one triggered.
  • The exertional heat illness emergency action plan.
  • 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.

Heat haze over an open field at midday, the conditions each state association's WBGT policy sets practice limits for

State by state

Same instrument, different bands — the WBGT forecast travels with you.

All state heat policies

Sources

  1. MSHSAA — Wet Bulb Globe Temperature - Heat Modification Policy, updated 6/25. Thresholds for high school and middle school, instrument, reading cadence, district procedure, definitions. Verified 15 Oct 2026.mshsaa.org/resources/SportsMedicine/WBGT-Recs-Heat-Humidity.pdf (opens in a new tab)
  2. MSHSAA — Sports Medicine page, mshsaa.org, which links the policy as the current WBGT recommendations and guidelines. Verified 15 Oct 2026.mshsaa.org/SportsMedicine/ (opens in a new tab)

MSHSAA documents are published at mshsaa.org (opens in a new tab).

Frequently asked

No. The MSHSAA requires a scientifically approved WBGT instrument at each practice when it is above 80°F. Flash's 6-hour outlook tells you where that reading is heading — a scheduling tool, not a compliance instrument.

The MSHSAA says middle school athletes need different WBGT readings and modifications because of less controlled timing, quality and quantity of participation. Their 2-hour cap starts at 84.0 and outdoor activity stops over 90.

No. A walk-through lasts no longer than an hour, with no conditioning, contact drills, protective equipment or full-speed drills.

Yes. The statewide policy covers practices and voluntary conditioning workouts in all sports, including during the summer.

Live demo · No sensors required for the forecast

See your own sites on the map before the next storm.

We'll load your locations, replay last season's strikes against Flash's predictions, and show you the alert log your safety officer would have received.

Book a demoSee pricing