Santa Ana Sequel: Exhausted Angelenos Brace For Another “Particularly Dangerous” Windstorm With Gusts To 100 MPH

As residents impacted by the Eaton and Palisades Fires were slowly returning to their homes — or where their homes used to be — another dangerous Santa Ana wind event is forecast to begin Monday that is expected to bring isolated gusts as high as 100 mph.

Firefighters have continued to benefit from a break in the weather, thanks to low clouds and good humidity levels. Containment of the Palisades Fire has grown to 52% while containment of the Eaton Fire has grown to 81%. But the National Weather Service warned that this week’s expected winds mean that “conditions are favorable for extreme fire behavior and rapid fire growth, which would threaten life and property.”

A familiar Red Flag Warning was issued for Los Angeles County from 8 a.m. Monday morning through 2 p.m. Tuesday. Per the NWS, “A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. Use extreme caution with anything that can spark a wildfire. Residents near wildland interfaces should be prepared to evacuate if a wildfire breaks out.”

Forecasters took the rare step of issuing a “particularly dangerous situation warning,” an extreme designation beyond a Red Flag Warning, for a large portion of Los Angeles and Ventura counties Sunday afternoon due to damaging Santa Ana winds and very low humidity. That region is outlined in purple below and skirts along the edges of both existing fires.

California Governor Gavin Newsom last week sought to put the designation into star relief last week, noting that such warnings had been issued four times in the past three months. The first preceded the Mountain Fire in Ventura in which 243 structures were destroyed. The second preceded the Franklin Fire in Malibu in December where 20 structures destroyed. The third preceded the Palisades and Eaton Fires which have destroyed close to 15,000 homes and counting. The fourth was the second round of winds last week that fanned those fires.

The particularly dangerous situation warning is in effect from noon Monday until 10 a.m. Tuesday for the Santa Clarita Valley, San Fernando Valley including Calabasas and Agoura Hills, Malibu coast, western Santa Monica Mountains recreation area, the Interstate 5 corridor, San Gabriel Valley and north of the 210 Freeway including Altadena and Glendora.

Here’s a portion of the NWS Forecast Discussion:

NE winds will start in the mtns a few hours before dawn. During the morning hours after sunrise the winds will accelerate and move out of the mtns into the vlys and then the coast. Gusts will start increase and will reach warning levels during the day. Max gusts across the csts/vlys will be between 55 and 65 mph and the mtns will see frequent 60 to 70 mph gusts with local ridgetop winds reaching 70 to 90 mph. These winds will be oriented in the typical NE Santa Ana direction. This direction will bring the greatest mtn wave potential to the San Fernando and Santa Clarita Vlys.

The winds will peak Monday evening and overnight and will extend into Tuesday morning before the upper support wanes and the sfc grads begin to relax.

PREDICTED WINDSPEEDS FOR MONDAY EVENING:

Forecasters say Isolated gusts of 80 to 100 mph are expected in most wind-prone mountain locations, such as the San Gabriel, western Santa Monica and Santa Susana Mountains.

And that won’t be the end of it.

Per the NWS:

Gusty offshore winds and widespread very low humidities will continue later Tuesday night through Thursday in much of these same areas. The strongest winds during this period are expected Wednesday night into Thursday morning with gusts in the 40 to 55 mph range. Minimum humidities are forecast to be in the 3 to 13 percent range overall, with very poor overnight recoveries. Due to the potential for continued red flag fire conditions, a Fire Weather Watch is also in effect for most of these areas from late Tuesday evening through Thursday evening.

Officials are urging residents to review their evacuation plans and make sure emergency kits are stocked with needed items should they have to evacuate.

The city of Los Angeles declared that red-flag parking restrictions would go into effect at 8 a.m. Monday and remain in effect until further notice.

Ironically, the latest National Weather Service forecast also posits “a 60 to 70 percent chance of rain next weekend with about 40 percent of the ensembles showing rainfall accumulations over half and inch for most of the coast and valleys.”

That could present yet another challenge to recovery efforts as well as potentially create mudslides in the recent burn scars and, as Los Angeles Public Works Department chief Mark Pestrella warned earlier this week, potentially toxic flows.

“Both areas suffered watershed damage burned to such a significance that we expect massive debris-laden flows when it rains,” he cautioned. “In an event that we have major rain, we do expect that all of the street areas and all of the communities will be impacted by debris flows that could be hazardous to human health. In order to address this, we are developing plans to capture and hold this debris back as much as we can during a rain event.”

Pestrella said his department was “assessing impact to the flood control system” in both the Palisades and Altadena areas. He reported his department is “already deploying labor forces into the area in order to ensure that the flood control system is ready — as well as our street system is ready — as much as possible for that rain event.”

City News Service contributed to this report.