The next round of rain heading toward the Bay on Tuesday, Wednesday, and Thursday will be the heaviest we've seen in a while. And in addition to warnings of high winds coming with the next band of storms, areas that saw significant burning during last year's wildfires are facing the threat of landslides as the ground becomes over-saturated.
Parts of the Santa Cruz Mountains were under evacuation orders Monday as officials warned of potential landslides in the burn scars of the CZU Lightning Complex fires. The National Weather Service (NWS) has revised its forecasts for the atmospheric river on its way, saying that much of the Bay Area will see 3 to 5 inches of rain, primarily between Wednesday and Thursday, with higher elevations seeing a possible 5 to 8 inches of rain. Meanwhile, the Tahoe area is bracing for a blizzard that could dump seven feet of fresh powder at higher elevations.
"There’s going to be a lot more moisture than we had thought,” says NWS meteorologist Matt Mehle, speaking to the Mercury News. “It’s been quite some time since we’ve seen a storm like this.”
This next weather event is one of those so-called "Pineapple Express" atmospheric rivers that take shape over the Pacific west of Hawaii, and which often deluge the Bay Area earlier in the rainy season. Due to this year's weak La Nina, the late arrival of big rain was well predicted by the NWS.
Sat imgry is capturing the genesis of our atmospheric river event west of Hawaii.— NWS Bay Area (@NWSBayArea) January 24, 2021
Notice the narrow band of brighter colors (indicates more moisture) elongating poleward.
This AR plume is fcst to take an atypical path towards CA, 1st overrunning over a weak ridge in East Pac. pic.twitter.com/nRwvW9XFir
Around 5,000 residents in the Santa Cruz Mountains were told to evacuate today, including in the fire-scorched areas of Felton, Ben Lomond, Brookdale, Bounder Creek, the Swanton area, and other rural spots.
"Debris flows pose a risk in hilly or sloped areas following large fires," reads a newly updated section of the Santa Cruz County website. "Residents within and below the CZU Lightning Complex burn area should be aware that the dangers to life and property from these hazards are significant and have a higher likelihood of occurring for several rainy seasons following a fire."
This map indicates multiple areas in red that are under orders, with the warning of "Immediate threat to life. This is a lawful order to leave now. The area is lawfully closed to public access."
The Mercury News harkens back to a landslide in January 1982 in Ben Lomond that destroyed 30 homes and killed 10 people.
"We are putting people on alert," said Santa Cruz County spokesperson Jason Hoppin. "This is the time to get your go-bag ready, and to line up plans to stay with a friend or book a hotel. These debris flows can be more dangerous than the fire. We had one death in the fire. We don’t want to exceed that number."
According to a forecast from the California Department of Conservation, mapped out by the Chronicle, parts of the Santa Cruz Mountains are looking at an 80-percent to 100-percent chance of a landslide.
A Flash Flood Watch is in effect starting Tuesday across recently burned areas of Sonoma and Napa counties as well.
⚠️Flash Flood Watch is in effect ahead of the upcoming #AtmosphericRiver 🌧️ event and is valid from Tuesday afternoon through Thursday afternoon for the North Bay, along with much of the San Mateo County Coast, Santa Cruz Mountains, and the Santa Lucia Mountains. #CaWx pic.twitter.com/IAk6j3v4nR— NWS Bay Area (@NWSBayArea) January 25, 2021
Meanwhile, the NWS has issued a High Wind Watch from Tuesday at 7 p.m. to Thursday morning, saying there is "a significant threat to property or life in North Bay Mountains, North Bay interior valleys, Coastal North Bay including Point Reyes National Seashore, San Francisco County, East Bay Interior Valleys, San Francisco Peninsula Coast, San Francisco Bay Shoreline, Santa Cruz Mountains, Santa Clara Valley including San Jose, East Bay Hills and the Diablo Range."
This is, of course, just what everyone needs — especially those who were impacted by this past season's never-ending wildfires and those whose just barely got through them unscathed. Because in this year of slow-moving apocalypse, if one thing doesn't get you, another just might.