National Weather Service issues Excessive Heat Warning for Phoenix area and Southwestern Arizona

The National Weather Service has issued an Excessive Heat Warning for multiple counties in Arizona due to dangerously high temperatures across the state.

According to officials, the warning went into effect at 10:00 a.m. on August 3, with the Valley expecting temperatures from 108°F to 113°F. Parts of Southwestern Arizona could even see temperatures of up to 118°F.

heat thermometer

A thermometer in Yucca, Arizona on Aug. 4, 2021 (Kolleen Lopez)


  • Maricopa, Pima, and Pinal from Aug. 3, 10 a.m. to 8 p.m., Aug. 4
  • La Paz, Mohave, and Yuma from Aug. 3, 10 a.m. to 8 p.m., Aug. 5
  • Graham and Greenlee from Aug. 4, 11 a.m. to 8 p.m.
  • Coconino County from Aug. 5, 12 p.m. to 6 p.m. Aug., 6

"High to Very High risk from heat-related impacts is expected for these areas," read a tweet made by the National Weather Service's Phoenix office.

Hiking trails closed amid extreme heat

The Phoenix Parks and Recreation Board approved a new pilot program for hikers to restrict hikers from using trails during the extreme heat.

Camelback Mountain and Piestewa Peak are closed due to excessive heat warnings.

Some hikers are aware of the new restriction policy.

Gregg Bach Phoenix Parks and Recreation says park rangers will talk to hikers during restricted hours on the mountain.

Those who continue to break the rules can be cited and fined $2,500 with 6 months in jail.

The pilot program runs through September 30th and is only enforced on days the National Weather service issues an excessive heat warning.


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Preventing heat exhaustion/heat stroke

The Arizona Department of Health Services stated the following precautions can be taken to prevent heat exhaustion or heat stroke:

  • Stay in air-conditioned buildings
  • Limit outdoor activity during the hottest part of the day (mid-day)
  • Check on at-risk friends, family, and neighbors at least twice a day
  • Drink water before, during, and after working or exercising outside

Driving in extreme temperatures

The Arizona Department of Transportation’s tips for driving in extreme temperatures include: 

Have sun protection: In addition to an umbrella, take sunscreen and a wide-brimmed hat and wear loose-fitting, light-colored cotton clothing.

Fuel up: Keep your tank at three-quarters full. Running out of gas, especially in a remote location, is dangerous in extreme heat.

Hydrate: Take a cooler to keep extra drinking water cold, and consider adding several frozen bottles of water to use for cooling off or to thaw and drink if needed. Make sure everyone, including pets, stays hydrated.

Get help: If your vehicle breaks down in extreme heat, call for assistance right away to reduce wait time, and run the AC. If the AC isn’t working, roll down all windows.

Wait safely: If the temperature inside your vehicle becomes too hot, everyone, including pets, should exit carefully and seek out or create a shaded area as far away from the travel lanes as possible. Be careful walking on the road surface, which can be hot enough to burn skin. Keep your shoes on and try to keep your pets’ paws off the pavement. If you are stopped along the highway, raise the front hood and turn on hazard lights. Please keep in mind that parking in tall brush can start a fire. 

Check your vehicle: You can help avoid breakdowns and blowouts by making sure your vehicle is in good operating condition. Check your air conditioner and coolant levels, top off any vital engine fluids and make sure your battery is up to par. Check your tire pressure, as the combination of under inflated tires and hot pavement can lead to a blowout.