Heat Advisory Issued for Northern Hill Country, I-35 Corridor, Coastal Plains
The National Weather Service has issued a heat advisory for several areas, with heat indices expected to reach 110 degrees.
2 reports on this incident · first at Aug 18, 2026, 1:56 a.m. ET
Earlier reports
Aug 18, 2026, 1:56 a.m. ETFirst report
Extreme Heat Warning in Force for Grand Canyon Country, From Tusayan to Supai
An Extreme Heat Warning 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 warning record issued by National Weather Service Flagstaff AZ 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 warning 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 warning 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.
Was this report accurate and useful?
Sources
Revision history
- Version 224 Aug 2026, 03:44current
Removed 'the fact set' from the first sentence, replacing with 'reports from'. Added place names to the headline.
- Version 118 Aug 2026, 05:56current
First published.
- Version 124 Aug 2026, 03:39
First published.
How we work
This site models an investigative reporter rather than a wire desk. The aim is the most complete, accurate and timely account we can assemble — all three, not a trade between them. Reports go out within minutes of the coverage they are built from, carrying context a newsroom would otherwise need a day and a records request to gather: what has happened at this place before, what the operator’s record is, which aircraft it actually was.
Reports are built from primary sources — accident and court records, official registries, weather observations, agency statements — and from reputable news organisations, each named where their reporting is used. Facts are extracted before anything is written, and every one must be supported by a quotation found in the source itself; the model that writes the report is given only those verified facts and never sees the article, so it cannot introduce a detail no source stated.
Where sources disagree we publish the disagreement, attributed, rather than picking a figure. Where a fact comes from a record rather than a reporter, we say so, and the language matches: an instrument reading is never described as something anyone confirmed. Some things are deliberately withheld — a suspect is not named until an agency names them on the record, victims until families or officials release them — and corrections appear as visible revisions, never as silent edits.
None of that makes a report true. A quotation check proves a source said something, not that it was right, and an automated system can be confidently wrong in ways the checks do not catch. If something here is wrong, the feedback above is how it gets found. The full methodology, including what we refuse to publish.