Arizona temp records toppled by deadly heat wave

Record-breaking heat across Arizona shattered temperature records Sunday and claimed at least four lives on hiking trails in and around Phoenix and Tucson over the weekend. Weather forecasters predicted little relief Monday, especially along the state's western edges.

Temperatures in Phoenix, Flagstaff, Tucson and Yuma broke daily records Sunday afternoon, according to the National Weather Service. Phoenix reached 118 degrees, Tucson 115 degrees, Flagstaff 93 degrees and Yuma soared to 120 degrees, that city's fourth-hottest day on record.

But the heat turned deadly for some. At least four deaths were attributed to the hot weather this weekend: a hiker in the Phoenix Mountain Preserve, another hiker on the Peralta Trail in the Superstition Mountains, a third hiker near Finger Rock Canyon outside Tucson and a fourth in Ventana Canyon, also near Tucson.

"It really shows how critical this heat can be and how it can really sneak up on you," said Capt. Larry Subervi, a Phoenix Fire spokesman, after a hiker was rescued at the Phoenix preserve. "When we deal with temperatures like this, it can just really be unpredictable how your body is going to respond."

Temperatures climbed quickly Sunday morning, and the records began to fall shortly after noon. Yuma broke its daily record at 12:20 p.m. with a reading of 117 degrees. The old record for June 19 was 115 degrees, set in 1960. By the end of the day, the new record was 120 degrees, which ties for the city's fourth-highest temperature.

At 12:59 p.m., Phoenix broke its daily record with 116 degrees at Sky Harbor International Airport. A few hours later, around 2:25 p.m., the temperature in Phoenix peaked at 118 degrees, making Sunday the fifth-hottest day on record at the airport. The old daily record of 115 degrees was set in 1968.

Tucson's record fell at 3:13 p.m., when a high of 115 degrees was recorded. The daily record had been 112 degrees, set in 1989. The new record also tied the mark as the third-highest recorded in the city.

Two more cities also shattered records Sunday, with a high in Flagstaff of 93 degrees and 102-degree high in Prescott, just two degrees shy of the hottest temperature ever recorded in that mountain community. Until this weekend, Flagstaff's daily heat record was 92 degrees, recorded in 1936, and Prescott's was 99 degrees, recorded in 1981.

The high temperatures are a result of a "pretty impressive high pressure ridge," said Andrew Deemer, a meteorologist with the National Weather Service in Phoenix.

Looking ahead to the start of the week, Deemer said the center of high pressure looks like it will be located to the west of Phoenix on Monday. He added that the National Weather Service is predicting temperatures in the low 120s in areas near the Arizona/California border.

Meanwhile, the projected high for Monday in Phoenix has been decreased slightly from last week's projections, but will still be hot — around 117 degrees.

The highest temperature in Arizona’s recorded history was 128 degrees, on June 29, 1994, in Lake Havasu City.

EXTREME WEATHER: The hottest day on record in Phoenix.

Temperatures are expected to remain above 110 degrees all week. The Valley is under an excessive heat warning that is set to remain in effect until 9 p.m. Wednesday.

Visitors to Phoenix were cautioned about the heat as they flew into the city Sunday afternoon.

"It's hot, hot, hot at 118 degrees," Southwest captain Scott Jeffrey Davis told passengers as Flight 1869 from New Orleans neared Phoenix. "It's torture. Stay hydrated and safe."

Others took to social media to share tips on how to stay cool, with memes and posts ranging from photos of pets in pools to grateful messages praising the modern marvel of air-conditioning. On Twitter, the hashtag #heatwave and #arizonaheat were trending throughout Sunday afternoon.

Residents are encouraged to take extra precautions, including drinking more water than usual and avoiding alcohol, sugar and caffeine, wearing light-colored clothing and taking frequent rest breaks in shaded or air-conditioned areas. Children and pets should never be left unattended in cars.

Everyone should learn to identify signs and signals of heat illness, which can include thirst, cramps, heavy sweating, nausea, headache and dizziness.

Those who are particularly susceptible include children younger than 4, adults older than 65, homeless people, outdoor workers, people who are overweight and people who are ill or take certain medications.

Last year there were 84 heat-related deaths in Maricopa County, according to county Department of Public Health statistics. The average since 2001 is 66.9 deaths each year.

On Saturday, a 25-year-old Phoenix man died while hiking near Gold Canyon. Sheriff's officials said they believed he died from extreme heat exposure.

A 28-year-old woman suffering from heat-related issues died after being airlifted from the Phoenix Mountain Preserve Sunday morning. She stopped breathing while biking with friends and was taken to the hospital in extremely critical condition.

The Pima County Sheriff's Department confirmed two deaths that appeared to be heat-related, a woman hiking on Finger Rock Trail and a man in Ventana Canyon. Sheriff's crews were involved in at least three heat-related rescues on Sunday, officials said.

Across Arizona, the weather service reported more than a dozen new heat records, including: 113 degrees in Cottonwood, 106 in Sedona, 104 at Winslow, 112 at Safford and 119 at Organ Pipe Cactus National Monument.

Republic reporter Yihyun Jeong contributed to this report.