FirstAlerts
Severe Weather

Extreme Heat Warning in Force for Grand Canyon Country, From Tusayan to Supai

Lower elevations of the Grand Canyon face dangerously hot conditions from 10 AM Tuesday to 8 PM MST Thursday, with 107 to 111 degrees forecast at Phantom Ranch.

By AI ReporterWritten Aug 18, 2026, 1:56 a.m. ET
Developing · checked 9h ago

Hazard products are revised and cancelled as conditions change. Check the National Weather Service for the current alert before acting on this report.

We last searched for new coverage of this at Aug 18, 2026, 12:41 a.m. ET — checked 9h ago.

An covers the lower elevations of the Grand Canyon from 10 AM Tuesday, August 18, 2026, until 8 PM MST Thursday, August 20, 2026, according to the record issued by at 9:28 PM MST on August 17, 2026 and posted in the weather service's raw alert product archive. The record lists one forecast zone, Grand Canyon Country, and names Tusayan, Supai, Grand Canyon Village, and Grand Canyon North Rim among the affected communities. Dangerously hot conditions are expected below 4000 feet, the states, with daytime temperatures ranging from 94 to 99 degrees at Havasupai Gardens and 107 to 111 degrees at Phantom Ranch. Most individuals will be at risk for heat-related illnesses without effective cooling or adequate hydration, especially with prolonged outdoor exposure, according to the same record. The notes that it is reserved for only the hottest days of the year and is issued when temperatures are expected to rise to dangerous levels. Day hikers on Bright Angel Trail should descend no farther than 1 1/2 miles from the upper trailhead, the weather service says. Between the hours of 10 AM and 4 PM, hikers should be out of the canyon or at Havasupai Gardens or Bright Angel campgrounds, and physical activity is discouraged. All hikers should have adequate gear, including a wide-brimmed hat, sunscreen, salty snacks, sufficient water, and electrolyte mix, the record advises, adding that doubling calorie intake helps maintain energy.

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  1. Version 118 Aug 2026, 05:56current

    First published.

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