
The streets of Las Vegas and Phoenix have been reduced to ghost towns as temperatures hit 118F and climbing during a punishing heat wave that has grounded planes and left door handles so hot they can leave people with burns.

Temperatures are predicted to reach 120F on the first day of summer in Phoenix, and the heat wave is threatening to bring the 'deadly' temperatures to several parts of Arizona, Nevada and California as well.

Las Vegas is likely to hit 117F on Tuesday, as excessive heat warnings cover almost all of California.

The National Weather Service has been forecasting Tuesday highs of 120F or above in Phoenix for the past several days, a number not seen in the desert city for more than 20 years.

'That's deadly heat no matter how you slice it,' weather service meteorologist Chris Breckenridge said.

American Airlines canceled more than 43 flights on Tuesday in Phoenix operated by regional jets because of the heat. Officials say when the temperature soars, it's harder for airplanes to take off.

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The first day of summer is being marked in the Southwestern part of the United States with a punishing heat wave that has caused flights to be canceled in Phoenix and health warning issued

At Phoenix Sky Harbor American Airlines regional jets sit on the tarmac as American Airlines says seven regional flights have been delayed and 43 have been canceled because of a heat wave as temperatures climb to near-record highs on Tuesday

Phoenix topped out at a record high of 119F on Tuesday, although some unofficial thermometers like this one hit 120

Chris Mitchell sprays water on his face to cool off in a Darth Vader costume along the Las Vegas Strip

People shield themselves from the sun while walking along the famed thoroughfare as the temperature reached record highs

Construction works improvise and find shade underneath an excavator to avoid the head in Phoenix, Arizona

The heat wave is threatening to bring 120 degree temperatures to several parts of Arizona, where it seems residents are staying in doors as the streets are empty in downtown Scottsdale (above)

By 2pm PST, it had already reached 118F, as the temperature is predicted to soar above 120F on Tuesday. An empty downtown Scottsdale is pictured above on Tuesday

The heat wave is threatening to bring the 'deadly' temperatures to several parts of Arizona, Nevada and California as well. An empty downtown Scottsdale is pictured above on Tuesday

The National Weather Service has been forecasting Tuesday highs of 120F or above in Phoenix for the past several days, a number not seen in the desert city for more than 20 years. An empty downtown Scottsdale is pictured above on Tuesday as residents and tourists opted to stay indoors in preparation for the heat

A child used a public water feature to stay cool as temperatures climbed to near-record highs Tuesday in Phoenix

The 120F weather that's expected in Arizona on Tuesday will be the hottest that it has been in the state so far in 2017. An empty downtown Scottsdale is pictured above on Tuesday

Tourist kept inside the hotels and casinos on the Las Vegas strip on Tuesday to stay cool as temperatures hit 117F

Misters blow out onto near-deserted streets in Las Vegas as a heat wave tied the city's all-time record high temperature

Patrons at the Mon Ami Gabi French restaurant inside the Paris hotel-casino try to keep cool as hot temperatures hit Las Vegas

Misters blow out from the front of Hexx Kitchen + Bar inside the Paris hotel-casino to keep patrons cool from the hot temperatures in on Tuesday Las Vegas, where temperatures hit 117F, tying the all-time record high temperature

The temperature in Las Vegas at 2pm PST were already at 113F and climbing thanks to the punishing heat wave. Above guests keep cool from the hot temperatures by hanging out by the pool inside the Planet Hollywood hotel-casino in Las Vegas

Officials have warned for people to stay inside on Tuesday in several Southwestern states due to the extreme temperatures outside. Above a young boy walks through misters to stay cool at the Grand Bazaar Shops in Las Vegas on Tuesday

Usually during the summer months the streets of Las Vegas can be seen packed with tourists, but Tuesday only a few people were spotted out in the heat. Above misters are seen at the Linq Promenade to keep patrons cool from the hot temperatures in Las Vegas

Las Vegas is currently under an excessive heat warning. Above patrons walk through misters to stay cool at the Grand Bazaar Shops in Las Vegas Tuesday

Las Vegas is likely to hit 114 degrees on Tuesday; it was already 113F around 2pm (PST) on The Strip. Above the sun reflects from the Mandalay Bay Hotel and Casino

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 118. 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 refueling stop.

Phoenix and Las Vegas are used to 110-degree heat, but temperatures above 115 are rare.

The current temperatures in several southwestern states are still climbing as the afternoon is just beginning on the West Coast

Tuesday night the temperature will cool down, but it will still be around 90 degrees in Phoenix and 85 degrees in Las Vegas

The heat returns on Wednesday as it's predicted to reach 118 degrees in Phoenix, which is only two degrees cooler than what is expected on Tuesday

Wednesday night again the temperatures will drop and Phoenix will be around 90 degrees while Las Vegas will be in the 80s

HOW EXTREME TEMPERATURES AFFECT FLIGHTS Extreme heat creates changes in the air density that make it harder for airplanes to take off. Airlines respond by imposing weight restrictions, such as carrying less cargo and fuel. But planes will need more speed to take off and a longer runway length to do that in extreme heat situations if the aircraft type can fully operate when temperatures are past 120 degrees. American Airlines pilot Shane Coffey also said that the extreme heat causes some pilots to have to use more thrust. Air density on a 90-degree day in Denver at more than 5,000 feet elevation is similar to a 120-degree day in Phoenix at 1,100 feet above sea level, he said. The maximum operating temperature for each aircraft type is based on manufacturer data: Airbus - 127 degrees

Boeing - 126 degrees

Bombardier CRJ regional aircraft - 118 degrees Advertisement

Phoenix hit 118 degrees Monday, tying the record for the date set last year.

The last time the city reached 120 was in 1995. A notorious heat wave in 1990 brought consecutive days at 120 degrees, including the record of 122.

Furthermore, 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.

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 warned.

For Thursday, the temperature will continue to drop, but it will still be a hot 114 degrees in Phoenix and Las Vegas

Weather service meteorologist Chris Breckenridge said: 'That's deadly heat no matter how you slice it.' Above the early morning sun rises over a replica of the Statue of Liberty at the New York-New York Hotel and Casino

The director of the Arizona Burn Center said second- and third-degree burns from touching hot items are common in the extreme heat. Above a woman walks her dogs early Tuesday morning in Phoenix

Phoenix and Las Vegas are used to 110-degree heat, but temperatures above 115 are rare. Above two people walk their dogs in Phoenix early Tuesday morning before it heats up outside

Above a hospital worker in Phoenix takes a break outside Tuesday morning in a bid to beat the extremely warm weather

At Phoenix Sky Harbor International Airport, departure signs show regional jet cancellations. American Airlines says seven regional flights have been delayed and 43 have been canceled because of the heat wave

The extreme heat is also spreading across California, as the Central Valley has bakes in unusually bad heat.

The Northern California city of Redding hit a June 18 record of 110 degrees on Sunday, which is 19 degrees above normal.

Forecasters predict that Death Valley could see 124 degrees on Tuesday.

Officials in Nevada are warning visitors that the Las Vegas 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 115 and 120 degrees despite the city's airport forecast to hit 114 Monday.

Phoenix hit 118 degrees Monday, tying the record for the date set last year. Above the sun rises over the mountains near a high school in Phoenix Tuesday

Above Steve Smith wipes sweat from his face as temperatures climb to near-record highs in Phoenix on Monday

Above Salvation Army volunteer Jackie Rifkin tries to keep cool at she works at a special Salvation Army hydration station to help people try to keep hydrated and stay cool as temperatures climb to near-record highs on Monday in Phoenix

Above Lori Mantz sprays water to cool down her horse Thor on Monday in Las Vegas. The heat wave brought broiling temperatures that were also felt in Arizona and Southern California, creating a public health hazard

Officials say 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.

Dr. Moneesh Bhow, medical director for Banner University Medical Center Emergency department, said the body's internal cooling mechanisms are ineffective when temps reach above 110 degrees.

In addition to the heat wave gripping the Southwestern part of the country, Gulf Coast states are preparing for a powerful weather system of their own

Tropical Storm Cindy formed Tuesday in the Gulf of Mexico and began churning heavy rain bands toward the northern Gulf Coast, where Louisiana shuttered flood gates and parts of three other states also braced for a risk of flash flooding

One of the ways the body cools itself is by radiating heat through the skin into the air, but that system reverses when external temperatures climb to 110 or higher.

'When that happens we have to rely on our second mechanism, which is sweating,' Bhow said. Sweat makes your skin feel cooler and some heat is removed as it evaporates.

He noted staying hydrated is crucial to perspiring and staying cool.

In addition to the heat wave gripping the Southwestern part of the country, Gulf Coast states are preparing for a powerful weather system of their own.

The third tropical storm of 2017, Cindy was expected to reach the northern Gulf Coast late Wednesday and then rumble inland over western Louisiana and eastern Texas on Thursday. Many cities are under a flood watch and flood warning

Heavy rain is predicted to fall through Thursday along the Gulf Coast states. Between five to eight inches could fall in New Orleans as Mobile, Alabama could get between eight to 12 inches of rain

Tropical Storm Cindy formed Tuesday in the Gulf of Mexico and began churning heavy rain bands toward the northern Gulf Coast, where Louisiana shuttered flood gates and parts of three other states also braced for a risk of flash flooding.

Alabama Gov. Kay Ivey issued a state of emergency because of the threat of torrential rains and other severe weather, including dangerous high tides and rip currents.

Double red flags snapped in the wind on the public beach at Gulf Shores in her state, warning visitors to stay out of the pounding surf.

The third tropical storm of 2017, Cindy was expected to reach the northern Gulf Coast late Wednesday and then rumble inland over western Louisiana and eastern Texas on Thursday.

The National Weather Service in Miami said Cindy was located early Tuesday afternoon about 265 miles south of Morgan City, Louisiana - or about 355 miles southeast of Galveston, Texas

Forecasters warned that rainfall totaling 6 to 9 inches and up to 12 inches in isolated spots was the biggest threat in southern parts of Texas, Louisiana, Alabama, Mississippi and the Florida Panhandle.

Already some flooding from outlying rain bands was reported on Alabama's Dauphin Island and flood control locks and gates were being closed along Louisiana's bayou-marbled coast as Cindy hovered nearly stationary - still well offshore.

Officials in various coastal Louisiana and Mississippi communities handed out sandbags as rain threatened low-lying areas along rivers and bayous.

The National Weather Service in Miami said Cindy was located early Tuesday afternoon about 265 miles south of Morgan City, Louisiana - or about 355 miles southeast of Galveston, Texas.