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What does CIF require?
Under state law AB 1653 and CIF Bylaws 503.K and 503.L, all CIF member schools must follow the CIF heat illness prevention and heat acclimatization policies. CIF requires schools to use WBGT, not the heat index, because it accounts for temperature, humidity, wind speed, sun angle and cloud cover in direct sunlight.
California spans all three region categories, so each school first finds its category on the CIF WBGT category map, then follows that column of the chart. Schools without a WBGT device use the NOAA WBGT forecast link CIF provides. Every practice and contest venue needs an easily accessible method for whole-body cooling, such as an ice tub, a "taco tarp" or ice towels.
Find your category
California has Category 1, 2 and 3 regions. The CIF WBGT category map decides which column of bands you follow.
WBGT required
CIF requires WBGT. Schools without a device take the reading from the NOAA WBGT forecast link in the policy.
Whole-body cooling
An ice tub, "taco tarp" or ice towels, easily accessible at all practice and contest venues.
Five-day acclimatization
Fall outdoor sports: one on-field practice a day, no longer than two hours, for the first five days.
The CIF WBGT threshold table
Five bands, read in degrees Fahrenheit from a WBGT measurement, not air temperature. Category 3 and Category 2 are shown; Category 1 is in the note. The row colour follows the Flash alert scale your athletic trainers already see in the app.
| Cat 3 | Cat 2 | Activity limit | Rest breaks | Football / field hockey equipment |
|---|---|---|---|---|
| < 82.0 | < 79.7 | Normal activities | At least three separate rest breaks each hour with a minimum duration of 3 min each | None listed |
| 82.2 – 86.9 | 79.9 – 84.6 | Use discretion for intense or prolonged exercise | At least three separate rest breaks each hour with a minimum duration of 4 min each | None listed |
| 87.1 – 90.0 | 84.7 – 87.6 | Maximum outdoor practice time is 2 h | At least four separate rest breaks each hour with a minimum duration of 4 min each | Helmet, shoulder pads, and shorts during practice |
| 90.1 – 91.9 | 87.8 – 89.6 | Maximum outdoor practice time is 1 h; no conditioning activities. Contests permitted with additional hydration breaks | 20 min of rest breaks distributed throughout the hour of practice | No protective equipment may be worn during practice |
| ≥ 92.1 | ≥ 89.8 | No outdoor workouts/contests. Delay practice/competitions until a cooler WBGT is reached | — | — |
Source: CIF Extreme Heat and Air Quality Policy, Step 2 WBGT chart, 2026-27 Constitution and Bylaws pp. 102–103 (cifstate.org), checked 15 Oct 2026. Ranges as printed. Category 1 bands: < 76.1, 76.3 – 81.0, 81.1 – 84.0, 84.2 – 86.0, ≥ 86.2. If the WBGT rises into the third band during practice, football and field hockey players may continue to work out wearing full pads without changing to shorts.
Where does Flash fit?
Flash is a forecast for planning, not an on-site meter: CIF modifications follow the WBGT reading for your venue. 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 category. 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 CIF's (Category 3)
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: 86 by 3 pm, into 87.1–90.0 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.
WBGT at the field: 85.3, the 82.2–86.9 band. Three 4-minute breaks per hour go on the plan and the ice tub is set up by the sideline.
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?
CIF makes the heat policy mandatory for member schools. Keeping these together means a question from CIF, your section, the district or a parent is answered from one folder.
- The school's region category from the CIF WBGT category map.
- WBGT readings with times and their source — an on-site device or the NOAA WBGT forecast — and the decision each one triggered.
- The acclimatization record for fall outdoor sports: the five-day period and, for football, the helmet and shoulder-pad days.
- The whole-body cooling setup at each practice and contest venue, and the emergency action plan around 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)
- Arizona (AIA)
- 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)
- 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
- CIF — Extreme Heat and Air Quality Policy, 2026-27 Constitution and Bylaws pp. 102–106. Cancel points, WBGT chart, acclimatization, air quality. Checked 15 Oct 2026.cifstate.org/governance/constitution/EXTREME_HEAT_AND_AIR_QUALITY_POLICY.pdf (opens in a new tab)
- CIF — WBGT region category map for California schools. Checked 15 Oct 2026.cifstate.org/sports-medicine/WBGT_Category.pdf (opens in a new tab)
CIF documents are published at cifstate.org (opens in a new tab).
Frequently asked
No. CIF modifications follow the WBGT for your venue, from a device or the NOAA WBGT forecast CIF links. Flash's 6-hour outlook tells you where that reading is heading — a scheduling tool, not a compliance instrument.
California covers all three categories. CIF publishes a WBGT category map; find your school on it and follow that column of the chart.
At the top band: no outdoor workouts or contests until a cooler WBGT is reached. In the band below it, contests are permitted with additional hydration breaks, but practice is capped at 1 hour.
Yes. Fall outdoor sports start with a five-day period of one on-field practice a day, no longer than two hours. In football, the first three days are helmets only, the next two add shoulder pads, and full pads begin on day six.