On this page · 8 sections
What does the AIA require?
Article 43.6 of the AIA Policies and Procedures covers heat acclimatization and exertional heat illness. Its WBGT activity modifications apply to all sports and training activities, with one exception: in-water work for swim and dive, where coaches weigh water temperature, shade, ice and water instead. Dry-land training for aquatic sports follows the same bands as everyone else.
The recommended equipment is a WBGT device equivalent to a Kestrel 5400. The reading is taken on the same playing surface as the practice or event, anytime it is over 80° F with high humidity, and every 30 minutes or sooner if the weather changes significantly. All monitoring and the recommendations that follow are documented. Arizona is identified as Region 3, so one set of bands covers the whole state.
Reading cadence
Anytime it is over 80° F with high humidity. Every 30 minutes, or sooner after a significant change in the weather.
The device
A WBGT device equivalent to a Kestrel 5400, read on the same playing surface as the practice or event.
Timed rest breaks
Breaks are set by the clock: every 20 minutes in the lower bands, every 15 minutes from 87.0 up.
Rapid cooling
Suspected exertional heat stroke is treated with cold-water immersion, 35–59°F, up to the neck if possible.
The AIA WBGT threshold table
Five bands, read in degrees Fahrenheit from the WBGT device on the playing surface, for Arizona as Region 3. The row colour follows the Flash alert scale your athletic trainers already see in the app.
| WBGT (°F) | Activity limit | Rest breaks | Equipment |
|---|---|---|---|
| < 82.0 | Normal | Minimum of 3-minute break every 20 minutes of activity | None listed |
| 82.1 – 86.9 | Use discretion for intense or prolonged exercise | Minimum of 4-minute break, every 20 minutes | None listed |
| 87.0 – 90.0 | Maximum practice time is 2 hours | Minimum of 4-minute break every 15 minutes | Helmet, shoulder pads, and shorts during practice |
| 90.1 – 91.9 | Maximum practice time is 1 hour. No conditioning activities | Minimum of 5-minute break every 15 minutes | No protective equipment to be worn |
| > 92.0 | No outdoor workouts. Delay practice until a cooler WBGT is reached | — | — |
Source: AIA Policies and Procedures, Article 43, Sports Medicine, 2026-2027, 43.6 item 6, Environment Monitoring and Activity Modification (pp. 155–156), checked 15 Oct 2026. Ranges as printed. If the WBGT reaches 87.0–90.0 after practice has started, players may continue in pants. In 90.1–91.9, off-campus sports need a designated adult within line of sight of all athletes.
Where does Flash fit?
Flash is a forecast for planning, not an on-site meter: the AIA bands are applied to the WBGT reading taken on your playing surface. 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 AIA 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 AIA's
6:30 pm · The reading that decides the day
The band you land in sets the clock, the break timer and the pads.
Flash 6-hour WBGT outlook for the practice field: 86 by 3 pm, into 87.0–90.0 by 4 pm. The athletic director flags the football session.
Decision: run at 4 pm under the 2-hour cap with a 4-minute break every 15 minutes, or push to 6:30 pm. The AD pushes. The bus, the trainers and the parents hear now, not at 3:45.
Reading on the playing surface: 85.2, the 82.1–86.9 band. A 4-minute break every 20 minutes goes on the plan, the reading is documented and the next one is due at 7:00.
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?
Article 43.6 says all environmental monitoring and the recommendations that follow should be documented. Keep these together so a question from the AIA, the district or a parent is answered from one folder.
- WBGT readings with times, taken on the playing surface every 30 minutes, and the modification each one triggered.
- The device used: a WBGT device equivalent to a Kestrel 5400.
- The acclimatization record for football and outdoor fall sports: practices per day, practice time and equipment stage for days 1–14.
- The emergency plan for exertional heat stroke, with the cold-water immersion tub and who runs it.
- 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)
- Arkansas (AAA)
- Colorado (CHSAA)
- Hawaii (HHSAA)
- Illinois (IHSA)
- Kansas (KSHSAA)
- Massachusetts (MIAA)
- 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
- AIA — Policies and Procedures, Article 43, Sports Medicine, 2026-2027. 43.6 Heat Acclimatization & Exertional Heat Illness Management Policy: WBGT bands, monitoring, acclimatization, treatment. Checked 15 Oct 2026.aiaonline.org/files/18079/article-43-sports-medicine.pdf (opens in a new tab)
- Grundstein et al., Regional heat safety thresholds for athletes in the contiguous United States, Applied Geography, 2015. The regional map the AIA cites for Region 3.ksi.uconn.edu/wp-content/uploads/sites/1222/2018/08/RegionalWBGT_2015_AppliedGeography.pdf (opens in a new tab)
AIA documents are published at aiaonline.org (opens in a new tab).
Frequently asked
No. The AIA bands apply to the WBGT reading taken on your playing surface. Flash's 6-hour outlook tells you where that reading is heading — a scheduling tool, not a compliance instrument.
Article 43.6 says to obtain WBGT anytime it is warm outside, specifically anytime it is over 80° F with high humidity, and to take it every 30 minutes or as needed after a significant change in the weather.
Not to in-water work. Aquatic coaches weigh water temperature and the availability of shade, ice and water instead. Any dry-land training follows the same WBGT bands as other sports.
Yes, for football and outdoor fall sports. Days 1–5 allow one practice a day of no more than 3 hours; days 1–3 are helmet only, days 4–6 add shoulder pads for football, and full equipment and contact begin from day 7.