The heat wave sweeping through California and the Southwest has broken records and is expected to continue through Tuesday.
"It's early in the heat season. Usually our hottest months are August and September. We're not even in July yet, but this is a massive high pressure system and it's just smothering," said Bill Patzert, a climatologist at the NASA Jet Propulsion Laboratory in La Cañada Flintridge.
On Saturday, the National Weather Service warned that temperatures could rise above 120 degrees in some desert areas. They predicted 100 to 115 degrees in valleys, 100 to 105 in lower mountains and up to 95 in coastal areas.
"We'll set record highs today," said National Weather Service meteorologist John Dumas, noting that Ojai, at 104 degrees, beat its previous record of 103, while San Luis Obispo tied its earlier record of 97.
The minimum temperature in Burbank last night clocked in at 74.
"That's making people most uncomfortable," Dumas says. "Everybody knows they will be hot by day, but when it doesn't drain down at night, it's a lot harder. If you can go to bed and cool off and get a good night's sleep, you can recover. But if you can't, it's a huge challenge to your day."
Phoenix was looking to set a new record, too. As of 3 p.m., it was 119 degrees, according to Accuweather. Las Vegas was at 113 and Death Valley 126.
A slight cooling starts Monday through July 4, though temperatures will still be above normal, Dumas said.
The last significant heat wave to trap Southern California was in 2009, when the region baked in unforgiving heat for two weeks.
In Death Valley, July marks the month with the most deaths and injuries such as dehydration, according to statistics, said Chris Stachelski, meteorologist from the National Weather Service's Las Vegas branch. Those most likely to get hurt are people who don't realize their limits, wander and become disoriented, he added.
Death Valley is usually about 12 degrees warmer than Las Vegas, with normal highs hovering around 114 degrees.
Stachelski predicted that temperatures there will hit 128 later today, inching up to 129 Sunday and Monday.
"All records," he said. "If you don't have a reason to go there, don't go there. The last time we were there to inspect the equipment, in May, it was only 98."
In Los Angeles, the heat is a particular concern to firefighters because it comes in a year of record dry conditions that have already sparked several major brush fires in the area.
Fireworks also went on sale Friday in some areas, adding another fire danger. Fireworks will be sold in 295 designated communities in the state through the Fourth of July.
Since January, the California Department of Forestry and Fire Protection has responded to about 2,900 fires, department spokesman Daniel Berlant said. In an average year, he said, it would have responded to fewer than 1,800 by this time.
Dry brush is a reason for the increase in fires, Berlant said. Current weather conditions are more typical of late August or early September, he said.
"We're in a long-term drought," said Bill Patzert, a climatologist with the NASA Jet Propulsion Laboratory in La Cañada Flintridge. "The situation is extremely crispy and dry. That equals incendiary."
Several agencies opened cooling centers — air-conditioned facilities where the public can escape the heat — around Los Angeles County. For information about the centers, call 211, or view an interactive map of the centers online.