High pressure system cranks up the heat across the West

Record High Heat for Southwest

PHOENIX (AP) — Much of the West was smothered in a blanket of heat Saturday with triple-digit temperatures hitting Phoenix, Los Angeles and other cities.

Above-normal temperatures were expected through the weekend as a high-pressure system centered over New Mexico acted like a lid to block cooler air, leaving valleys, deserts and mountains high and very dry.

SEE ALSO: Western wildfires: Wind, heat, dry land fueling large blazes

Authorities warned people not to leave small children or pets in cars, where temperatures can quickly soar. Los Angeles and other cities were keeping libraries and other facilities open late to serve as cooling shelters for those without air conditioning.

Phoenix broke a daily record Saturday, reaching 115 degrees, topping a 1992 record by 3 degrees, the National Weather Service said.

"Stay inside if you can," Dan Leins, a weather service meteorologist in Phoenix, said. "It's dangerous, regardless of how acclimated you are to the climate, because it can be deadly."

Mike Stephens took precautions for an early-morning run in Estrella Regional Park, a desert and mountain wilderness area in Phoenix. He carried 1 ½ liters of water and was careful not to overdo it.

"You have to know what your body can do," he said.

In the desert 50 miles south of Phoenix, Maricopa County Sheriff's deputies rescued three migrants who had been out of water for at least three days. Teams were searching for about 17 others who were heading from the Mexican border north.

Photos of last month's similar heatwave on the East Coast:

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East coast heatwave
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High pressure system cranks up the heat across the West
NEW YORK, NY - AUGUST 17: People relax on a hot afternoon at the Astoria Pool in the borough of Queens on August 17, 2015 in New York City. The main pool, the biggest in New York City and administered by the New York City Department of Parks and Recreation, sees over 3,000 people on a typical summer weekday. New York city is in the middle of a heat wave, with temperatures in the high nineties and with a heat factor making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 20: A woman uses a sun umbrella along the boardwalk at Brighton Beach in Brooklyn on August 20, 2015 in New York City. The National Oceanic and Atmospheric Administration (NOAA) announced on Thursday that July was the planet's warmest month on record. July's average temperature was 61.86 degrees Fahrenheit, beating the previous global mark set in 1998 and 2010 by about one-seventh of a degree. NOAA began keeping records in1880. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 21: A man stands in the water on a sultry morning at Coney Island in Brooklyn on July 21, 2015 in New York City. Despite an overcast sky, thousands of New Yorkers headed to area beaches to cool off from the heat and humidity. The hot weather is expected to break tomorrow with temperatures expected only in the 80's. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 17: A child waits to get into the Astoria Pool in the borough of Queens on August 17, 2015 in New York City. The main pool, the biggest in New York City and administered by the New York City Department of Parks and Recreation, sees over 3,000 people on a typical summer weekday. New York city is in the middle of a heat wave, with temperatures in the high nineties and with a heat factor making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 17: People enjoy a hot afternoon at the Astoria Pool in the borough of Queens on August 17, 2015 in New York City. The main pool, the biggest in New York City and administered by the New York City Department of Parks and Recreation, sees over 3,000 people on a typical summer weekday. New York city is in the middle of a heat wave, with temperatures in the high nineties and with a heat factor making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 21: Life guards do their daily exercises on a sultry morning at Coney Island in Brooklyn on July 21, 2015 in New York City. Despite an overcast sky, thousands of New Yorkers headed to area beaches to cool off from the heat and humidity. The hot weather is expected to break tomorrow with temperatures expected only in the 80's. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 28: A woman sits in a line for ice cream along the East River in Brooklyn on a sweltering hot afternoon on July 28, 2015 in New York City. With temperatures in the 90's and the heat index feeling over 100 degrees, New Yorkers of all ages have been flocking to pools, beaches and air conditioned rooms to try and stay cool. More hot and humid days are forecast for the remainder of the week. (Photo by Spencer Platt/Getty Images)
People enjoy a warm day at the Astoria Park Pool in New York on August 16, 2015. At 330 feet in length, the Astoria Park Pool is the largest in New York City and one of the largest swimming facilities in the United States. AFP PHOTO / KENA BETANCUR (Photo credit should read KENA BETANCUR/AFP/Getty Images)
NEW YORK, NY - JULY 21: A man looks out at the Verrazano Bridge from a pedestrian promanade on a sultry morning in Brooklyn on July 21, 2015 in New York City. Despite an overcast sky, thousands of New Yorkers headed to area Parks and beaches to cool off from the heat and humidity. The hot weather is expected to break tomorrow with temperatures expected only in the 80's. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 20: A woman cools off in the shade at Brighton Beach in Brooklyn on August 20, 2015 in New York City. The National Oceanic and Atmospheric Administration (NOAA) announced on Thursday that July was the planet's warmest month on record. July's average temperature was 61.86 degrees Fahrenheit, beating the previous global mark set in 1998 and 2010 by about one-seventh of a degree. NOAA began keeping records in1880. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 20: A man who goes by Ricky Obama tries to keep cool in the heat at Brighton Beach in Brooklyn on August 20, 2015 in New York City. The National Oceanic and Atmospheric Administration (NOAA) announced on Thursday that July was the planet's warmest month on record. July's average temperature was 61.86 degrees Fahrenheit, beating the previous global mark set in 1998 and 2010 by about one-seventh of a degree. NOAA began keeping records in1880. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 20: Empty water containers are viewed in the trash at Brighton Beach in Brooklyn on August 20, 2015 in New York City. The National Oceanic and Atmospheric Administration (NOAA) announced on Thursday that July was the planet's warmest month on record. July's average temperature was 61.86 degrees Fahrenheit, beating the previous global mark set in 1998 and 2010 by about one-seventh of a degree. NOAA began keeping records in1880. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - AUGUST 20: A man uses a sun umbrella along the boardwalk at Brighton Beach in Brooklyn on August 20, 2015 in New York City. The National Oceanic and Atmospheric Administration (NOAA) announced on Thursday that July was the planet's warmest month on record. July's average temperature was 61.86 degrees Fahrenheit, beating the previous global mark set in 1998 and 2010 by about one-seventh of a degree. NOAA began keeping records in1880. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: Bottles of water sit for sale at a street vendor on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: People line-up for ice cream in Manhattan on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: A woman holds an umbrella on a Manhattan street on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: A woman carries a tired child along a Manhattan street on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: People sit on the steps of the James A. Farley Post Office Building on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: People wear shorts and other light clothing as they walk on a Manhattan street on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: People line-up for ice cream in Manhattan on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: People rest in the shade along a Manhattan street on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: A woman holds a sun umbrella in Manhattan on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
NEW YORK, NY - JULY 20: A woman holds an umbrella on a Manhattan street on one of the hottest days of the summer on July 20, 2015 in New York City. More than 20,000 homes and businesses in and around New York City have lost power as the electric network has been stressed due to the intense heat. New York and much of the East Coast has experienced temperatures in 90's for the past few days with the humidity making it feel over 100 degrees. (Photo by Spencer Platt/Getty Images)
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The National Weather Service issued warnings of excessive heat throughout Southern California into Saturday night, with some areas expected to see highs of 10 to 15 degrees above normal, said Scott Sukup, a weather service meteorologist in Oxnard.

The mercury hit 96 degrees in downtown Los Angeles, with the San Fernando Valley and other inland valleys ranging up to 107. Palm Springs hit 118, tying an old record set in 1992, and Death Valley's high reached 123, according to the weather service.

The high in Las Vegas was 109 degrees.

The Western heat wave began Thursday and was expected to continue through Sunday.

"There's been a big area of high pressure that was over New Mexico and it's been expanding westward," Sukup said.

The heat, coupled with low humidity, has increased the fire danger in California, where some two dozen major fires in recent weeks have destroyed thousands of acres of trees and brush left bone-dry by years of drought.

Winds were light "but it's so hot and dry right now that it's not going to take a lot of wind to spread fires," he said.

A brushfire that erupted Friday afternoon in forest foothills north and east of Los Angeles quickly grew to 4 square miles, torched several cabins and remained out of control Saturday. Firefighters worked in triple-digit heat and several were treated for dehydration or heat exhaustion.

Temperatures were expected to be cooler in California's coastal regions, with highs in the 80s.

About 1 million people were expected to hit 32 miles of Los Angeles County beaches this weekend, county lifeguard Capt. Kenichi Haskett said.

But they might have to share the water with some prickly guests.

Calm, warm waters have drawn the barb-tailed stingray to the surf line, where they bask in the shallows and burrow in the sand, Haskett said.

"We could have a couple of hundred at Santa Monica Bay," he said.

About two dozen people were stung Thursday and Friday, he said.

The venomous stings are painful but not lethal.

Stingrays aren't aggressive but will respond if stepped on. Haskett said people can avoid stings by doing the "stingray shuffle" — shuffling their feet through the sand when entering the water to give the stingrays warning.

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Associated Press writer Robert Jablon contributed to this story from Los Angeles.


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