After a long stretch of record-breaking heat and wildfires in Southern California, much of the state will see below-average temperatures, drizzle and even early snowfall this week.
The National Weather Service issued the first snow warning in 20 years for parts of the Sierra Nevada over the weekend. In Southern California, where three fires have scorched more than 115,000 acres and burned uncontrollably for days, a rapid cooldown and high humidity levels have already provided some relief to firefighters trying to contain the blazes.
The eldest of the three, fire on the bridge In the Angeles National Forest, the fire was 11% contained as of Monday morning, while line fire San Bernardino County had 42% control. Airport fireThe wildfire that broke out in Orange County last week and spread to Riverside County was 31% contained as of Monday.
“It’s a really nice change in temperatures and a relief after the heat wave,” said Brian Lewis, a meteorologist with the National Weather Service in Oxnard.
The low pressure trough, which has already dropped temperatures 5 to 10 degrees below normal in Southern California, could bring light rain late Tuesday night through Thursday. Parts of Los Angeles County could get less than a tenth of an inch of rain. The foothills could get up to a quarter of an inch.
Temperatures are expected to range from 60 to 65 degrees at the beach and 70 to 75 degrees in inland areas. Downtown Los Angeles, which reached 111 degrees earlier this monthLewis said that the temperature here has dropped by 40 degrees.
In the Sierra Nevada, elevations above 8,000 feet from Fresno County to Yosemite could see about 3 inches of fresh snow by Monday night. More could follow, said Antoinette Cerrato, a meteorologist with the National Weather Service in Hanford.
“The low pressure system is bringing in some very cold air from the Arctic region and that’s going to cause early snowfall in the region,” Cerrato said.
Experts say while the cooler weather is expected to help fire crews, it doesn’t mean the fire season will be slow.
“This is a very small event in the overall fire season,” said Robert Foxworthy, a spokesman for the California Department of Forestry and Fire Protection. “Our weather fluctuates as patterns change, so the fact that we have some cool weather now and the fire season is slowing down doesn’t necessarily change the overall outcome of the fire season.”
The most damaging and destructive fires in Southern California typically occur between October and December, when the Santa Ana winds blow, which can help turn small fires into massive blazes.
Persistent rain and a dry summer have left grasses and rich fuel ripe for fires. The National Interagency Fire Center’s seasonal forecast released in August said fires along the Southern California coast are more likely than normal through December because of “the increased likelihood of dry weather and a delayed start to the rainy season.”
The cold weather isn’t expected to last long. California could see hot, dry weather conditions again next month, which could lead to an increase in fires, said UCLA climate scientist Daniel Swain. Written in a recent blog post.
“The offshore wind season has not fully begun yet, and if/when Santa Ana or Diablo winds arrive this fall, fire danger will increase accordingly (unless sufficient rain occurs). So enjoy low wildfire risk for the next 7-10 days across most of the state,” he wrote.
Firefighters battling the Airport Fire, which had burned 23,519 acres as of Monday, anticipate that cooler temperatures and higher humidity will reduce fire activity in the coming days.
Orange County Fire Authority Capt. Steve Concialdi said the fire had 100% relative humidity Sunday night, allowing firefighters to raise containment lines. The fire has destroyed 120 homes and three businesses.
High winds hampered aircraft flights over the Bridge Fire on Sunday night, but crews were able to bring some control of the blaze. As of Monday morning, the fire had burned 54,690 acres.
Firefighters are primarily focusing on the northwestern portion of the fire, which is the most active, to protect the communities of Big Pines and Pinon Hills. The fire on the eastern side is less active but still poses a threat to the Mount Baldy area, according to Cal Fire.
Firefighters will continue to focus on the northwestern portion of the fire on Monday night. L.A. County Fire spokesman Kenichi Haskett said cool temperatures are expected to help firefighters reduce the fire’s large growth, but winds will pose another obstacle.
Haskett said winds were expected to shift from southwest to northwest between 4 and 8 p.m. Monday, which could fuel the fire and cause blazes away from the main fire.
The fire destroyed 54 buildings and damaged 13 others. Three people, including civilians and firefighters, were injured.
Winds gusting up to 25 mph near the Line Fire in San Bernardino County helped fan the flames Sunday night as they tore through dry vegetation in the area. The fire, which has grown to 39,026 acres by Monday, has destroyed one structure and damaged four others.
In lower elevations, firefighting conditions are expected to be more favorable because of cooler temperatures, higher humidity levels and cloudiness. In elevations above 5,000 feet, temperatures are expected to be slightly warmer and drier. Highs are expected to be in the mid-50s, Cal Fire spokesman Rick Carhart said.
“This fire is not completely out yet and there is still more work to be done,” he said.
