Skip to content
Flash Weather
An empty floodlit high school football field at dusk with heat haze over the turf, the kind of New Jersey practice the NJSIAA WBGT flags govern

State heat policy · New Jersey (NJSIAA) · Checked 15 Oct 2026

New Jersey high school heat policy: NJSIAA WBGT thresholds, practice limits, and how to plan around them

The NJSIAA Heat Participation Policy sets five WBGT flags, green to black, that decide how long practice runs, how many rest breaks each hour needs and what helmeted sports may wear. It covers practices and games in every sport. Here are the bands as NJSIAA prints them, what to keep on file, and how a 6-hour WBGT outlook lets you move practice instead of cancelling it.

Flash Meteorology Desk · Checked against the NJSIAA Heat Participation Policy (njsiaa.org) · Checked 15 Oct 2026 · 7 min read

WBGT outlook · Field B · 6 hours

12:58

85.182921 pm2 pm3 pm4 pm5 pm6 pm
  • 4 pm · 86.2 — in 85.1–88.0
  • Under 85.1 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 NJSIAA require?

The Heat Participation Policy must be followed by all sports, for outdoor practices and games, and has no specific ending date. It works alongside the NJSIAA Pre-Season Heat Acclimatization Policy and follows modified American College of Sports Medicine guidelines on when practice is scheduled, how much rest and hydration time each hour needs, and the WBGT levels at which practices and contests are modified or stopped.

An instrument scientifically approved to measure WBGT must be used at each practice and game. The athletic trainer, a certified designee or an individual appointed by the athletic director takes an on-site reading 30 minutes before activity and at least every hour during it. Every reading is recorded, and any modification or cancellation goes on the NJSIAA Heat Participation Policy Record Chart.

  • Reading cadence

    On site, 30 minutes before practice or a game, then at least every hour during it.

  • Games count too

    Officials hear the WBGT reading at least 30 minutes before a game. At a black flag the game is postponed 30 minutes and re-read.

  • Rest breaks and cooling

    Shaded rest with unrestricted fluids; helmets off. Above 85.0: ice towels, spray bottles of ice water or equivalent.

  • Cold-water immersion

    From 80.0, a 150-gallon tub or a tarp, water under 60°F, within 5–10 minutes of the site. Below 80.0, a cooler with ice and towels or a tarp.

The NJSIAA WBGT threshold table

Five flags, read in degrees Fahrenheit from the on-site WBGT device: one table for the whole state. The row colour follows the Flash alert scale your athletic trainers already see in the app.

NJSIAA Heat Participation Policy WBGT guidelines for New Jersey high school sports: five flags from under 80.0 to over 90, with practice-length, rest-break and equipment rules
WBGT (°F)Activity limitRest breaksFootball, lacrosse, field hockey
Under 80.0 · GreenNormal activitiesProvide at least three separate rest breaks each hour of minimum duration of 3 minutes each during workoutNone listed
80.0 – 85.0 · YellowUse discretion for intense or prolonged exercise; watch at-risk players carefullyProvide at least three separate rest breaks each hour with a minimum duration of 4 minutes eachNone listed
85.1 – 88.0 · OrangeMaximum practice time is 2 hoursFor all sports: provide at least four separate rest breaks each hour with a minimum duration of 4 minutes eachAll helmets and shoulder pads must be removed for practice and conditioning activities
88.1 – 90 · RedMaximum length of practice is 1 hour. For all sports: there must be no conditioningFor all sports: there must be 20 minutes of rest breaks distributed throughout the hour of practiceNo protective equipment may be worn during practice and there must be no conditioning activities
Over 90 · BlackNO OUTDOOR WORKOUTS. Delay practice until a cooler WBGT level is reached——

Source: NJSIAA Heat Participation Policy Guidelines (njsiaa.org), checked 15 Oct 2026. Ranges as printed. If the WBGT rises into 85.1–88.0 during practice, football players may continue to work out wearing football pants without changing into shorts. In games, protective equipment is worn according to the rule book, but in sports that require it, equipment comes off and active cooling starts during the built-in water breaks.

Where does Flash fit?

Flash is a forecast for planning, not an on-site meter: NJSIAA compliance uses the on-site WBGT reading and the Record Chart. 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 NJSIAA flags. 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, 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 NJSIAA's

An empty high school practice field under a hazy hot sun with a shade canopy and water coolers on the sideline, the setting for a New Jersey NJSIAA WBGT planning day

6:00 pm · The reading that decides the day

The flag you land on sets the clock, the breaks, the pads and the tub.

  1. Flash 6-hour WBGT outlook for the practice field: 84 by 2 pm, into 85.1–88.0 by 3 pm. The athletic director flags the football session.

  2. Decision: run at 4 pm under the 2-hour cap with helmets and shoulder pads off and 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: 83.2, the 80.0–85.0 yellow flag. Three 4-minute breaks per hour go on the plan, the cold-water tub is filled and the reading is recorded.

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

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

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

What does the athletic director keep on file?

NJSIAA compliance checks look for a WBGT device, Record Chart entries for every practice and game that needed a modification, and the signed policy. Keep these together so a question from the NJSIAA, the district or a parent is answered from one folder.

  • WBGT readings with times — 30 minutes before activity, then at least every hour — written or data-logged.
  • The NJSIAA Heat Participation Policy Record Chart for every practice or game that was modified or cancelled.
  • The written and signed-off Heat Participation Policy document.
  • The emergency action plan, including heat injury and cold-water immersion or another approved cooling technique.
  • 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. NJSIAA — Heat Participation Policy, with FAQ, guidelines, Record Chart and Cold Water Immersion Tub Policy. Checked 15 Oct 2026.njsiaa.org/sites/default/files/documents/2020-10/njsiaa-heat-participation-policy-080619.pdf (opens in a new tab)
  2. NJSIAA — Heat Participation page, health and safety. Checked 15 Oct 2026.njsiaa.org/health-safety/heat-participation (opens in a new tab)
  3. NJSIAA — Guidelines, Policies and Procedures 2024-25, Heat Participation Policy. Checked 15 Oct 2026.njsiaa.org/sites/default/files/documents/2024-08/njsiaa-policies-and-procedures-24-25-.pdf (opens in a new tab)

NJSIAA documents are published at njsiaa.org (opens in a new tab).

Frequently asked

No. NJSIAA compliance is decided by the reading from a scientifically approved WBGT instrument at the practice or game site. Flash's 6-hour outlook tells you where that reading is heading — a scheduling tool, not a compliance instrument.

No. It must be followed by all sports and has no specific ending date. Coaches and athletic trainers follow it whenever WBGT readings are elevated.

Yes. Officials must hear the on-site reading at least 30 minutes before a game. At a black flag the game is postponed for 30 minutes, then re-read, and does not resume until the WBGT falls below a black flag.

The athletic trainer, a certified designee, or an individual such as a coach appointed by the athletic director.

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