An atmospheric river storm – enough to compete with some of the extreme storms that separated Southern California in recent winter – bombed the coast, which added to the ghosts that destroyed landslides and flooding throughout the region.
The storm is expected to arrive in Southern California sometime before Valentine’s Day, and is expected to be the strongest winter, according to the Oxnard National Weather Services Office.
It has the potential to drop heavy rains on the hills and in the valleys – 2 to 4 inches above the coast and in the valleys, and spread across the south on the hills and foothills. In Santa Barbara and San Luis Obispo counties, there is a 60% chance of rainfall and 30% chance of Los Angeles and Ventura counties.
The storm along the powerful storm on January 9, 2023 forced mass evacuation of Montecito and other communities, and the rainfall could also be extreme – age arrested in floods in San Luis Obispo County .
“Of course, people should be prepared, and this will be the wettest period we have so far started at the beginning of the rainy season,” said Ryan Kittell, a meteorologist at Oxnard National Weather Service.
“People should prepare for the worst,” Kittell said. Heavy rain can cause dirt and debris to slide off hillsides and fall into roads and can crash into houses and other buildings.
Animated infographics show debris flow
Kittel said the storm could have begun as early as Tuesday night or Thursday night for Santa Barbara and San Luis Obispo counties. The highest threat is expected to be Wednesday night to Thursday night.
“Of course, if you’re in those fragile areas around burning scars, track the weather every day to see what’s predicted trends and what seems to be the most likely outcome,” Kittell said. “Be prepared for the worst hope.”
Between February 12 and February 14, there is 60% rainfall in Santa Barbara and San Luis Obispo counties, which increases the risk of debris flow and mudslides .
(National Meteorological Administration)
Santa Barbara and San Luis Obispo counties may see rainfall of 12 to 24 hours or more, with precipitation dropping by half an inch to one inch per hour or more Long time. Rain rates of half an inch or more per hour can cause a large amount of debris flow, where water can pick up mud, rocks, branches, and sometimes huge boulders at speeds of more than 35 mph.
Kittle said rainfall rates in that range “usually cause some flooding problems, especially for the most recent burn areas.” These include the burning area of the 2024 Lake Fire, which is in Los Olivos The Santa Barbara County Mountains to the north burned 38,664 acres.
With rainfall rate of 1 inch per hour, flooding can be triggered anywhere, especially in roads and creeks, Kittell said.
In extreme rainfall scenarios, there is a 20% chance in Santa Barbara and San Luis Obispo County, and forecasters estimate that 4 to 8 inches of rain may occur.
“Two to four [inches of rain] It will definitely cause us problems, but 4 to 8 will be very extreme. Kittell said. “Recalling some of the predictions of some of our recent very extreme events over the past few years, if that happens, the total number we are studying will be very close and close to January 9, 2023. transparent
The biggest difference, though, is that the storm is one of a series of powerful systems that hammer California from late December 2022 to mid-January 2023. The season has become drier – one of the driest rainiest in modern California history – “So there may be less impact,” Kittle said.
For Los Angeles and Ventura County, there is a 50% chance of moderate rain, in addition to the 30% chance of heavy rainfall. A storm may arrive Wednesday morning or Thursday night. The most threatening time is Thursday morning to Friday morning – Valentine’s Day.
Kittel said moderate events could lead to road flooding, but the risk of debris flow remains low, although it still exists.
Kittel said the “quite high risk” of heavy rainfall that would cause downpours so strong that there is a risk of debris flow in the nearest burning areas of the region.
Recently, burning areas are at risk of landslides in heavy rains, as the soil is no longer anchored by healthy vegetation. The heat of fire makes it harder for the soil to absorb water, and ash tends to clog the soil, so water is more likely to flow along the surface rather than seep into it.
The Hanford Meteorological Services Office said the storm is also expected to affect travel along the Kern County pass in the San Joaquin Valley and the Sierra Foothills.
Once it reaches San Diego and Orange County and the Inland Empire, the storm will become weaker and have relatively moderate effects in the Sacramento Valley. Reno’s Meteorological Services Office said the Sierra Nevada can see 2 feet or more feet of snow, while the area around Lake Tahoe’s elevation may see “the biggest snow event to date this season.”
The San Francisco Bay Area could face moderate risks of flooding and tree damage, Monterrey’s Meteorological Services Office said.
The upcoming storm was a higher rainfall than expected in the system leaving Southern California on Friday. Over the two-day period ending Friday at 5 p.m., Santa Monica was 1.26 inches; Beverly Hills, 1.46 inches; Porter Ranch, 1.53 inches; Alhambra, 1.64 inches; City of Los Angeles Center, 1.71 inches; East Pasadena, 2.07 inches; and Malibu Hills, 2.5 inches. The mountains in Los Angeles County saw up to 3.32 inches of rain.
California may be enough to end the “high fire season” and transition to the “low fire season” which may be enough to allow Southern California to rain enough to moisten the vegetation, to the point where “there is any risk of a fire to the rest of the spring, Will be very small.”
Before this decision is made, there is a need to have a conversation with many agencies, including firefighters: “But we will certainly move in that direction.”
Rain has been around 2 inches in downtown Los Angeles since the start of October 1, almost all since late January. The typical average at this time (about half of the traditional rainy season) is 7.93 inches. The annual average is 14.25 inches.
Meteorologists say the area requires 2 to 4 inches of rain, with high fire seasons widely spread.
