Back to Extreme Heat Watch

Action guide

Excessive heat warning: what to do when the alert is active

When an excessive heat warning is active, do not rely on a general reminder to drink water. Assign specific actions: reduce exposure, change schedules, communicate clearly, and watch for heat illness.

Best forFor teams that need a checklist they can turn into assignments during a dangerous heat window.

First hour checklist

Start with timing. Identify the worst heat window, list exposed roles, and decide which tasks can move, shorten, or pause. Then confirm water, shade, cooling, communications, and medical escalation.

OSHA heat guidance emphasizes planning, supervision, water, rest, shade, training, and extra protection for new or returning workers. Schools and events should apply the same logic to students, guests, volunteers, and vendors.

  • Name the heat decision lead for the site.
  • Move high-exertion tasks away from peak heat.
  • Create smaller rotation groups with planned recovery.
  • Send clear notices by role, not one generic message.
  • Record the alert source, timing, and changes made.

Do not wait for symptoms

Heat illness can escalate quickly. Preventive changes should happen before people report symptoms, especially when workers are new, returning after time away, wearing protective gear, or performing heavy work.

If someone has confusion, fainting, seizures, very high body temperature, or stops sweating with hot skin, treat it as an emergency and call 911 while cooling the person immediately.

Quick answers

What should a supervisor say during an excessive heat warning?

Give the exact schedule change, the rest and water expectation, who is checking the team, where cooling is available, and what symptoms must be reported immediately.

Can a live event continue during an excessive heat warning?

It depends on official guidance, venue conditions, medical capacity, crowd exposure, and local rules. At minimum, review gate timing, queues, shade, cooling, water access, staffing rotations, and cancellation language.