Evacuation warnings were set to go into effect in Los Angeles County Thursday evening as the Armory River nears the fire’s edge while bringing new risks of flooding and mudslides.
Under the condition of the storm, it was very predictable, in this city it would see 2.62 centimeters. However, the forecast remains unfavorable and variable.
There are almost one-in-four chances of low rainfall – but – in the high area, in the area of 1.39 inches, but there is an equal chance of a very strong anointing of 4.81 inches in the same period.
Either way, it’s fire season,” said Ryan Kitell, a meteorologist with the national service office in Oxnard.
“If we end up getting the rain we’re expecting, this will certainly get us closer to the end of the fire season,” Kitell said, and gives Southern California a chance to contend with the Santa Ana wind event.
That would be a far cry from last year, when southern California was put through a record dry streak over the fall and winter that left vegetation stunted and underwritten. Those are on the “charts” set up by the illegal Santa Ana Wind, reviving the rapid spread of the fires of Eaton and the Palisades, a position among the most deadly and destructive in history that kills Californians.
Meteorologists say Southern California needs 3 to 4 inches of widespread rain in the high-elevation areas of the fire season to end it. Downtown La has already received 1.41 inches, almost all from one stormy day in October.
Last year, Downtown La saw only 0.07 inches from early October to mid-November. On Jan. 7 – The day Eaton and Palisades were driven to life – the city had received only 0.16 inches. It wouldn’t be until February, after the blazes had already destroyed Altadena, Pacific Palisades and Malibu, that the region saw enough rain to bring on the fire season.
But the silver lining of the coming storm also affects gray. Rain of this severity could cause damaging mud and debris.
Evacuation warnings start from 6 PM Thursday to Sunday 11 Sunday in areas near the latest scars of the recent heat, due to the risk of mudslides and debris. These include areas near Palades, Eaton, Kenneth, Sunset and the January firefighter fires.
There are many reasons California has faced unusual fire danger in recent years. Climate change has fueled extreme heat, shaping shrubs and grasses. Residential development has increased in fire-prone areas. Energy infrastructure and failure to put out non-flammable fires were blamed after recent devastating fires.
All this increases the stakes of the California Dance which has already been woven between the winds of Santa Ana – the power and heat of which many have been cooked by fire – and the arrival of the rainy season.
The expectation of this in the fall was considered to be damaged by the return of La Niña in the Central and Eastern Ocean. Californians often think of LA Niña, a natural weather pattern that involves high ocean temperatures, as a drought pattern, and the myth of El Niño as synonymous.
There is a reason for that. California experienced Eltic rains during a significant El Niño in 1982-83. Another in 1997-98 coincided with the worst flooding on the west coast, and the latest February on record. That was followed by the mighty LA NI 17A in 1998-99, which was largely suspended.
Recently, 2020-21 and 2021-22 are both LA NIñA’s seasons, and they are more damaged than usual for Downtown Los Angeles.
But using La Niña as only your crystal ball can show is disappointingly clever. As noted by meteorologist Jan Null, California’s most expensive flood seasons — in 2016-17 and 2022-23 — came during La Niñas.
This week’s rains are not a telling sign that the rest of this fall and winter will be particularly aggy. A number of LA Niñas have come in wet only to open the storm door only to close suddenly, according to Kitell.
Uncertainty continues as to how strong the storm will be in Southern California, although there are expected to be some signs of rain as it approaches the system.
Forecasters expect two peaks in the La Hearn area – Thursday night into Friday morning, and Saturday, Kitell said. But there will still be rain all day and night on Friday.
The highest chance of rain for Ventura County is Thursday night through Saturday night, and in La County from Friday morning to Saturday night. There is also a 10% to 20% chance of thunderstorms Friday night and Saturday during the day, with the risk of damaging human-damaging winds and even a hurricane, the weather service said.
“We wouldn’t be surprised if we hear a storm report or two if that high system plays out on Saturday,” Kitell said.
A five-minute tornado touched down in Santa Cruz County last December, damaging three trees, downed and power trees, overhanging trees and damaging road signs.
In Orange County, the Inland County and San Diego County, moderate rain is expected on Friday, and the heaviest rain could hit Saturday. There is a 10% to 20% chance of thunderstorms across the region on Friday, and a 20% to 30% chance on Saturday.
Until Sunday, the most likely scenario for long beaches is to receive 2.38 inches; Redondo Beach, 2.48; Oxnard, 2.49; Thousand oaks, 2.63; Santa Clarita, 2.77; Covina, 2.89; and Santa Barbara, 3.59.
San Diego could get 1.5 to 2 inches; Riverside, San Bernardino and Escondido, 2 to 2.5 inches; San Clemente, 2.5 to 3 inches; and Anaheim and Irvine, 3 to 4 inches, according to the Weather Service.
Even the desert can impress the rain. Palm Springs could get 1 to 1.5 inches, and Joshua Tree Pak Park could get 1.5 to 2 inches.
Saturday is a particular concern, as there is a high degree of uncertainty about the weather. As a result, that day carries a high risk of significant impacts, including dangerous floods.
“There are very high levels of uncertainty,” said Dave Munyan, a forecaster with the San Diego Weather Bureau.
Another scenario could be a storm sitting just off the coast of California, which would produce “many hours of strong, wet, very worrisome currents,” Kitell said.
On Saturday, “the possibility of heavy rainfall, which could trigger flash flooding and/or debris flow, is on the table,” Kitell said.
There is also the possibility of strong winds from the south, southeast and east, which may cause delays at Los Angeles International Airport.
It is possible, however, that Saturday is for some fullness. Because that system will be part of what’s known as a “low cut,” where a low pressure system is cut off from the jet stream, Kitell said, “It’s just going to be around the top and it’s very difficult to predict.”
One of those conditions, he said, involves a lot of low pressure brushing and pulling down the coast, “and actually produces very little of any rain for our area.”
The low-level system is “very volatile and very weak, and any little wobble in the path of that low, and where it’s followed by rain, and how long we can see each other,” Munyan said.
Expect to see road flooding and heavy traffic delays on Saturday, Kitell said. If rainfall amounts are on the high end of the forecast, quick water rescues may be necessary if people are stuck in flood control stations or streams, Kitell said.
Meteorologists expect “at least some debris flows and canyon rock and mud,” especially in areas that have recently burned, Kitell said. Rainfall amounts are expected to be between 0.25 and 0.5 inches per hour, with gusts as high as 1 inch per hour.
Mudflows and debris flows – the type of rainwater that picks up rainwater and other materials as the course moves quickly down the hill – said Kitell.
Kitell said the risk of damaging mudslide damage is low Thursday and Friday, “but Saturday, especially if there is rain,” especially if rain is at the end of the forecast. There is a 20% to 30% chance of significant debris flows on Saturday, he added.
Topanga Canyon Boulevard between Pacific Coast Highway and Grand View Drive will close at 10 PM Thursday due to high volume heavy traffic, according to the California Department of Transportation. The road is expected to remain closed from Friday morning onwards and possibly through the weekend.
Significant snow accumulation is not expected in the Southern California mountains for this storm. In the San Bernardino Mountains, most of the snow will be on the highest peaks, about 10,000 feet above sea level or higher.
In the Sierra Nevada, snow levels are expected to fall to 8,000 feet above sea level around Tahoe and Mono County from Thursday night into Thursday morning. Mammoth Mountain is moving its opening day to Saturday because of the storm, but Tahoe-Areas Ski Resorts plans to open Nov. 21; and Palisades Tahoe, November 26.
For those traveling through the Sierra Passes in Mono County, forecasters warned that about 6 inches of snow is expected to fall, and travelers should be prepared for delays or road closures. In Yosemite National Park, up to 6 inches of snow could accumulate at elevations of 8,000 feet above sea level on Thursday.
Forecasters said they expect the storm to hit the San Francisco Bay area and the Sacramento Valley beginning Wednesday night. The most significant impact was expected to be strong winds, with possible gusts of 50 to 60 mph. Some tree damage is possible, and strong winds can make driving difficult for high profile vehicles. Minor urban and minor recreational flooding is possible.
San Francisco and San José could get 1 to 1.5 inches
Looking ahead to next week, there is a chance of rain on Monday, and Thursday, in southern California. But at this point, meteorologists expect those storms to have minimal impacts.
