The official start of summer is just days away, and while you might be feeling the heat here, what we’ve got is nothing compared to the mainland.

Triple-digit temperatures are popping up from California to Nevada. The scorching temperatures could spell disaster for families heading to the mainland for a summer vacation.

That’s if your flight even gets off the ground.

KHON2 found an Ewa Beach family heading first to Los Angeles, then Las Vegas.

“We are really afraid of the heat now that we heard how hot it is there,” said Glenda Somera.

At 9 p.m. Las Vegas time, it was still 107 degrees, and the temperature is supposed to hit 115 on Tuesday.

Sienna Somera says her friend in Vegas told her it was even too hot to go swimming.

“So their pool, she couldn’t even go in,” said Sienna Somera. “Her foot, she just touched it for one second and then she pulled it out.”

Nevada is under an excessive heat warning for the next four days, but the punishing heat is affecting the entire Southwest, including Colorado, Utah, and Arizona, with Phoenix expecting the temperature to reach as high as 119 degrees.

American Airlines even canceled dozens of Phoenix flights because of that, and the heat wave is even being felt in California.

Los Angeles will be hot, but nothing like the desert parts of the state.

Mariah Phommachanh is flying to Los Angeles and Las Vegas.

“I’m excited about going,” she said. “I’m not too worried about the heat, because it’s already pretty hot down here, so it’s just going to be a little bit hotter.”

Get ready for more of this hot weather. University of Hawaii researchers say this is going to be a future trend all over the world.

According to a study published in Nature Climate Change, 74 percent of the world’s population will be exposed to deadly heat waves by 2100 if carbon gas emissions continue to rise at current rates.

Even if emissions are aggressively reduced, the percent of the world’s human population affected is expected to reach 48 percent.

“We are running out of choices for the future,” said Camilo Mora, associate professor of geography and lead author of the study. “For heat waves, our options are now between bad or terrible. Many people around the world are already paying the ultimate price of heat waves, and while models suggest that this is likely to continue, it could be much worse if emissions are not considerably reduced.”

The National Weather Service advises people in hot areas to drink plenty of fluids, stay out of the sun, wear lightweight clothes, and don’t leave kids or pets in unattended vehicles.Click here for more information.