PHOENIX - Airlines cancelled flights in Phoenix and doctors urged people to be careful around concrete, playground equipment and vehicle interiors Monday as a punishing heat wave threatens to bring temperatures approaching 49 Celsius to parts of the Southwestern U.S.
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 was forecast to hit 47 Celsius on Tuesday on the first day of summer, and excessive heat warnings 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 49 or higher in Phoenix for the past several days, a number not seen in the desert city in more than 20 years, but it now predicts 48.
"That's deadly heat no matter how you slice it," weather service meteorologist Chris Breckenridge said.
Here are a few things to know about the heat wave:
AIRLINES WATCHING THE HEAT
When the temperature soars, it's harder for airplanes to take off.
American Airlines cancelled nearly 40 flights on Tuesday in Phoenix operated by regional jets because of the heat. The airline also said it will allow Phoenix passengers flying during the peak heat Monday through Wednesday to change flights without a fee.
American Airlines spokesman Ross Feinstein said the smaller regional jets flown by its partners can't operate once the temperature hits 47. That maximum 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.
Feinstein said the carrier 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 refuelling stop.
HITTING 49 IS RARE
Phoenix and Las Vegas are used to 43-degree heat, but temperatures above 46 are rare.
Phoenix hit 47 degrees Monday, tying the record for the date set last year.
The last time the city reached 49 was in 1995. A notorious heat wave in 1990 brought consecutive days at 49 degrees, including the record of 50.
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 degrees on Sunday.
It could be worse: Death Valley could see 124 degrees 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.
Weather service meteorologist Ashley Allen says the Strip's tall, close buildings and long stretches of concrete cause the area to heat quickly and cool slowly.
She 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 and 49 degrees despite the city's airport forecast to hit 45 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.
The director of the Arizona Burn Center said second- and third-degree burns from touching hot items are common in the extreme heat. Dr. Kevin Foster 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 Arizona emergency rooms every year because of heat-related illnesses.
Homeless people comprised one-third of heat-related deaths in 2016, according to county records. Most of the others involved people with non-functioning air conditioners.
Kurt Dickson, an emergency room doctor at Banner Health in Phoenix, said people have a range of heat illnesses during the summer months, including fatigue, heatstroke and severe sun burns.
