SUN SHIELD A worker wears a large hat,wet with water, to protect herself from the sun while cleaning the seats at Dodger Stadium in Los Angeles, California. —AP
PHOENIX, ARIZONA — Airlines canceled flights in Phoenix and doctors urged people to be careful around concrete, playground equipment and vehicle interiors on Monday as a punishing heat wave threatens to bring temperatures approaching 48.9 degrees Celsius (120 degrees Fahrenheit) to parts of the US Southwest.
Arizona is seeing the most stifling temperatures, but the wrath of the heat wave is being felt across Nevada and California as well.
Las Vegas is forecast to hit 47°C (117°F) on Tuesday on the first day of summer, and excessive heat warnings are expected to cover almost all of California.
Despite the dangers, the weather may not be as bad as originally expected.
The National Weather Service had been forecasting Tuesday highs at 48.9°C or higher in Phoenix for the past several days, a number not seen in the desert city in more than 20 years.
“That’s deadly heat no matter how you slice it,” said Chris Breckenridge, a weather service meteorologist.
Here are a few things to know about the heat wave:
Airlines watching heat
When the temperature soars, it’s harder for airplanes to take off.
On Tuesday, American Airlines canceled nearly 40 flights in Phoenix because of the expected peak heat on Monday through Wednesday.
The airline said the smaller regional jets flown by its partners could not operate once the temperature reached 47.7°C (118°F). The maximum limit is set by Bombardier, the manufacturer.
Larger airliners made by Boeing and Airbus have higher maximum operating temperatures, but airlines still need to closely monitor the weight of the jets during the heat.
American Airlines began limiting sales on some flights to prevent the planes from exceeding maximum weight for safe takeoff in the hot conditions.
Airlines can use other strategies for limiting weight during hot weather, such as not fueling completely, then making a refueling stop.
Hitting 48.9°C is rare
Phoenix and Las Vegas are used to temperatures of 43.3°C (110°F), but temperatures above 46.1°C (115°F) are rare.
Phoenix hit 47.7°C (118°F) on Monday, tying the record for the date set last year.
The last time the city reached 48.9°C was in 1995. A notorious heat wave in 1990 brought consecutive days at 48.9°C, including the record of 50°C (122°F).
The heat is spread across California. The Central Valley has been baking in unusually bad heat, and the northern California city of Redding hit a June 18 record of 43.3°C on Sunday.
It could be worse: Death Valley could see 51.1°C (124°F) on Tuesday.
Sweltering Las Vegas
Visitors should be aware of a little-known fact about the temperatures in the gambling mecca: The Strip is often hotter than the rest of the city.
According to weather service meteorologist Ashley Allen, the Strip’s tall, close buildings and long stretches of concrete cause the area to heat quickly and cool slowly.
Allen says it’s hard to predict exactly how hot the Strip will get because the weather service does not get official readings there, but temperatures could reach somewhere between 46.1 C and 48.9 C on Monday.
Burn risks
It gets so hot in Phoenix that stores put coverings over door handles so people don’t burn their hands. Steering wheels and car shifters can be too hot to touch when getting into a car. And the pavement can burn the paws of pets.
Dr. Kevin Foster, the director of the Arizona Burn Center, said second- and third-degree burns from touching hot items were common in the extreme heat.
He warned people to be extra careful around concrete, car interiors and playground equipment, especially young children who have sensitive skin.
Pavement and concrete can be dangerous for pets, Foster said.
Health hazards
The heat is a serious public health hazard in places such as Phoenix and Las Vegas.
The county that is home to Phoenix had 130 heat-related deaths in 2016, the highest number in more than a decade.
The Arizona Department of Health Services says nearly 2,000 people visit the state’s emergency rooms every year because of heat-related illnesses.
Homeless people made up one-third of heat-related deaths in 2016, according to county records.