Southern California is facing a significant Santa Ana windstorm that is expected to bring dangerous and destructive conditions.
Gusts of 50 to 70 mph are forecast Tuesday afternoon through Wednesday morning, with localized maximums reaching up to 100 mph in high areas.
Areas such as the Santa Monica Mountains, Hollywood, Burbank, Beverly Hills and Malibu are at high risk.
“Residents should stay indoors and away from windows,” the National Weather Service (NWS) office in Los Angeles warned, citing a “potentially deadly and destructive windstorm.”
The winds are also expected to create “extreme fire conditions” in areas already parched by ongoing drought.
“The three wettest months in California are typically January, February and March,” said Jayme Laber, NWS senior hydrologist. News week. “So far, Southern California has been dry to below normal. The lack of precipitation in southern areas has kept vegetation very dry and more likely to produce large fires if fires start.
A firefighter battles intense flames during the Maria Fire in November 2019, driven by extreme Santa Ana winds with gusts reaching 80 mph. Similar dangerous winds are forecast for Southern California this week.
David McNew/Getty
What are Santa Ana winds?
The Santa Ana Winds are dry, powerful winds that sweep across Southern California, from the inland deserts to the coast.
These winds are driven by high pressure systems over the Great Basin, where cooler air flows to lower elevations near the Los Angeles Basin. As air moves downslope, it compresses, heats and dries, creating conditions ripe for wildfires and property damage.
Santa Ana winds can be powerful enough to damage power lines, buildings and trees while spreading wildfires at alarming rates.
What causes Santa Ana winds?
Santa Ana winds form when strong high pressure systems in the western interior force cooler air toward Southern California. The air temperature increases as it falls and its relative humidity decreases, creating hot and dry conditions.
For this event, a high pressure system over the Great Basin combines with a developing storm in northwest Mexico.
“Strong winds will be the product of a larger weather pattern,” AccuWeather meteorologist Gwen Fieweger said in the advisory.
These conditions can sustain gusty winds for 12 to 24 hours, although stronger events may persist for several days.
Do Santa Ana winds only affect California?
Santa Ana winds are specific to Southern California, but similar wind events occur globally. In the Rocky Mountains, Chinook winds bring rapid warming and dry air, often melting snow.
In Europe, Foehn winds share these characteristics. These winds occur when air is pushed downward from high altitudes, warming and drying as it descends and is compressed.
Is January a weird time to get Santa Ana winds?
Although Santa Ana winds typically peak in October, they can occur anytime from late September to early spring.
January events are not unusual, especially in La Niña years like this one. La Niña conditions, marked by cooler-than-normal sea surface temperatures in the equatorial Pacific, tend to bring drier weather to Southern California.
“Being dry in southern areas and wetter in northern areas of the state is what we can generally expect when we have La Niña,” Laber said. “La Niña conditions are expected to continue throughout the winter. »
Risks from the current wind storm in California
Dry, gusty winds and parched vegetation are creating “extreme fire conditions,” according to the NWS. Even a small spark could start a wildfire capable of spreading quickly across the landscape.
Downed power lines could compound that risk, meaning utility companies are likely to cut off power to large swaths of people while crews work to repair whatever blows out.
Winds reaching hurricane force levels in some areas are likely to cause damage and blow debris as well.
“Fast, dangerous winds like these can cause significant property damage,” said Ryan Kittell, a meteorologist with NWS Los Angeles. News week.
Large vehicles and aircraft face significant risks from strong gusts, making travel likely Tuesday and Wednesday.
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