School Heat Safety in the USVI: A WBGT Guide

WBGT for Schools: Recess, PE & Field-Day Safety

Schools make daily outdoor-heat calls, recess, PE, athletics, field trips, andWBGT turns those calls into one defensible number. Because children heat up faster than adults, a WBGT-based policy protects them more reliably than watching the thermometer.

Last updated July 9, 2026 · Live data refreshes every 15 min

A schoolyard at midday is a full-exposure environment: open blacktop, little shade, and children who sweat less efficiently than adults and rarely stop themselves when they overheat. That combination is exactly what makes clear, written heat policy so valuable, and why the policy should key off WBGT, not air temperature.

Why children need a lower bar

Children have more skin surface per pound of body mass, so they gain heat from the environment faster; their sweating system is less developed; and they are less likely to recognize or act on early warning signs. Treat every WBGT band a notch more cautiously for younger students, and keep the youngest and any medically vulnerable children under the closest watch.

A simple, defensible policy

Low / Elevated (below 84.7°F): normal outdoor activity; ensure water access and encourage shade.
Moderate (84.7 to 87.7°F): shorten outdoor time, require water breaks, favor shaded areas, ease intensity.
High (87.8 to 89.7°F): brief, shaded, low-intensity time only, or move indoors.
Extreme (89.8°F+): indoor alternatives; postpone outdoor PE, athletics, and field events.

Make it work in practice

One source of truth. Have staff check the live WBGT for the campus at decision time, so recess and dismissal calls are consistent.
Water and shade as defaults. Bottles allowed, shade available, and breaks built into every outdoor block.
Train staff. Recess monitors, PE teachers, and coaches should all recognize heat exhaustion and know the emergency signs.
Athletics & trips. Apply the coach guidance to teams, and check the band before any outdoor field trip.

USVI note. Island campuses are breezy, which helps, but a calm, sunny afternoon can still push the schoolyard into the moderate or high band. The live reading, not the season, should drive the call.

Sources

CDC. Extreme Heat and Children's Health. Centers for Disease Control and Prevention.
NFHS. Heat illness prevention for school athletics.
U.S. NWS. WBGT. weather.gov/ict/WBGT

Frequently asked questions

How can schools decide when it is too hot for recess?

Set a written policy that keys off WBGT bands rather than air temperature: normal outdoor time in the low bands, shortened and shaded time in the moderate band, and indoor alternatives at high and extreme. A single defensible number makes the call consistent and easy to communicate to staff and parents.

Are children more vulnerable to heat than adults?

Yes. Children have a higher surface-area-to-mass ratio, sweat less efficiently, and may not recognize or report early symptoms. They heat up faster and need closer supervision, more frequent water, and shorter exposure than adults at the same WBGT.

What should a school heat policy include?

WBGT-based thresholds for outdoor activity, mandatory water access and breaks, shade requirements, modified or indoor alternatives, staff training on heat-illness signs, and clear guidance for athletics and field trips. Tie the thresholds to a live source everyone can check.