The National Weather Service issued an Excessive Heat Warning for the Grand Canyon and Coconino County beginning at 11 a.m. on August 5. The alert will end at 8pm on August 6th.

Warnings are valid for altitudes below 4,000 feet. The Bureau of Meteorology is forecasting dangerously hot conditions, with daytime temperatures ranging from 99 degrees at Havasupai Gardens to 110 degrees at Phantom Ranch in the Grand Canyon.

For the latest observations and alerts, see: weather warning page.

Federal climate data show that the Southwest has been noticeably hotter in the last decade. The region has endured the most significant warming in the country during this period, and federal meteorologists said the increase reflected the effects of global warming.

In Phoenix and its surrounding areas, the developed areas are noticeably hotter than the surrounding desert due to the urban “heat island” effect, where exposed asphalt, concrete and roofs absorb heat from the sun, increasing temperatures.

People who know:

What is the difference between heat stroke, heat exhaustion, and dehydration?

hot weather tips

The Arizona Department of Health Services offers tips for preventing heat-related illnesses.

• Drink water: If you stay indoors all day, drink at least 2 liters of water per day. People who spend time outdoors should drink 1-2 liters per hour they are outdoors.
• Dress for the heat: Wear light, light-colored clothing. Always apply sunscreen to exposed skin. Wear a hat or use a parasol when outdoors.
• Eat small meals and eat more often. Avoid foods high in protein that increase metabolic heat.
• Monitor people at risk. Check your friends, family, and others for signs of heat exhaustion or heat stroke.
• slow down: Strenuous exercise should only be done during the coolest part of the day, between 4am and 7am.
• Please stay indoors.
• Get a break: Take a break in a cool place when exercising outdoors on a hot day.