Excessive heat warnings issued across Arizona as records could tumble

Beginning July 4, the National Weather Service issued excessive heat warnings for Maricopa County, Coconino County and Pima County, as heat records could fall across the state in the upcoming days.

Maricopa County will be under an excessive heat warning from 10 a.m. on Independence Day through 8 p.m. on July 8. Afternoon temperatures are expected to reach 110 to 116 degrees, according to the weather service.

South-central and southwest Arizona cities, including Scottsdale, Glendale, Mesa, Queen Creek and Phoenix, were issued a heat warning beginning on July 4 and lasting until 8 p.m. July 9. The area was expected to reach between 109 and 118 degrees.

Phoenix will be on a records watch for several days over the warning period as temperatures were forecast to be close to daily records, weather service meteorologist Alex Young said.

"Five out of the next seven days look potential for at least tying the record," Young said.

For July 5, the daily record is 116 degrees with a forecasted high at the same temperature. Meteorologists will also be watching for records on July 6 as the forecasted high of 115 degrees comes close to the daily record of 116 degrees.

The most likely day to break a record will be Monday, Young said, as the forecasted high of 116 degrees may beat the daily record of 115 degrees.

An excessive heat warning for the lower elevations of the Grand Canyon was issued about 11:30 a.m. July 4 and will expire at 8 p.m. July 9. Temperatures in the area were expected to range from 107 to 114 degrees.

Coconino County also received a heat warning for Lake Powell near Page, Marble and Glen canyons starting at 11 a.m. July 4 and lasting until 8 p.m. July 9. Temperatures in the area were expected to be between 105 and 112 degrees.

South-central Pinal County, the Tohono O'odham Nation, the Tucson area and western Pima County will be under heat warnings from 11 a.m. July 5 until 8 p.m. July 6. Temperatures were expected to be between 109 and 114 degrees, with areas west of Tucson seeing the hottest conditions, the weather service said.

For the latest watches and warnings, see our weather alert page .

Climate data from the federal government shows the Southwest has grown significantly hotter during the past decade. The region has endured the most pronounced warming in the country during that period, an increase that federal meteorologists say clearly reflects the influence of global warming.

In Phoenix and surrounding areas, developed areas have grown significantly hotter than the surrounding desert through the urban “heat-island” effect, in which exposed asphalt, concrete and roofs soak up heat from the sun and push temperatures higher.

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

Hot weather tips

The Arizona Department of Health Services has tips to prevent heat-related illness:

• Drink water: Drink at least 2 liters of water per day if staying inside all day. Those who spend time outdoors should drink 1 to 2 liters per hour they are outside.
• Dress for the heat: Wear lightweight and light-colored clothing. Sunscreen should always be applied to exposed skin. Wear a hat or use an umbrella when outdoors.
• Eat small meals and eat more often: Avoid foods high in protein that increase metabolic heat.
• Monitor those at risk: Check on friends, family or others for signs of heat exhaustion or heat stroke.
• Slow down: Do strenuous activity only during the coolest hours of the day, between 4 and 7 a.m.
• Stay indoors.
• Take breaks: Take a break in a cool place when doing physical activity outside on a hot day.

This article was generated by The Arizona Republic and USA TODAY Network using data released by the National Weather Service. It was edited by a staff member.

This article originally appeared on Arizona Republic: Excessive heat warnings issued across Arizona as records could tumble