Update: Flash-flood warning expires for Alisal Fire burn area in Santa Barbara County
Update, 12:05 p.m.: A Flash Flood Warning for the Alisal Fire burn area on the Gaviota Coast expired at 11:15 a.m. without major issues reported, but emergency managers remained watchful as an early season storm was dumping inches of rain on Santa Barbara County.
“The Flash Flood Warning for Alisal Fire burn scar has expired. There is no longer an immediate threat of significant damaging debris flows. Scattered showers will continue until noon or 1 p.m.,” the NWS said midday Monday.
Original story:
A shelter-in-place order went out to cell phones in the Alisal Fire burn area of the Gaviota Coast Monday morning, warning people about potential for “life threatening flooding and debris flows” in the area, and advising people to stay inside, go to the innermost room in their home, or to higher ground such as a second floor.
The wireless emergency alert followed the National Weather Service issuing a flash flood warning for the Alisal Fire burn area, advising people to move immediately to higher ground and move away from the burn scar area.
NWS meteorologist David Sweet said radar showed a “very narrow band of intense rainfall” west of Gaviota as of 8 a.m., as the storm’s heaviest rainfall moved into the Alisal Fire burn area.
The NWS had already issued a flash flood watch for the burn area on the Gaviota Coast, and warns the rainfall rates up to 1 inch per hour could produce significant debris flows and mud flows.
“I would say in terms of heaviest rainfall rates, it’s getting there now, really close; This is the time now to really keep a close watch on it right now,” Sweet said around 8 a.m.
The storm is expected to drop 1 to 3 inches of rain on the Santa Barbara South Coast area, and the concern is that high-intensity rainfall could cause post-fire flooding and debris flows for the Alisal Fire that started two weeks ago and is still not completely contained.
Refugio Pass recorded 0.91 inch per hour rainfall rates, the NWS said, and “flash flooding with mud and debris flows likely in the burn scar.”
The flash flood warning is in effect through 11:15 a.m. Monday.
“The expected rainfall rate is 0.75 to 1 inch per hour, with 30 minute rates likely exceeding 0.55 inches. Flash flooding with debris flows is expected to begin shortly. Excessive rainfall over the burn scar will result in debris flows moving through the Alisal burn scar. The debris flows can consist of rock, mud, vegetation and other loose materials,” the NWS wrote in the warning.
Flash flooding is likely at Refugio State Beach and El Capitán State Beach, according to the NWS.
Evacuation orders are in effect for the area, and search-and-rescue teams spent most of Sunday afternoon going door-to-door to notify residents.
“The greatest threats are to roads, including but not limited to Refugio Road and Highway 101, with a smaller chance of impacting structures,” the NWS said.
The Union Pacific Railroad tracks also run along the coastline within and downhill of the burn area.
Sweet said that the timing of debris flows is hard to predict, but if there are any, they typically would happen slightly after a period of peak rainfall.
“Anything from minutes to an hour or so after the peak rainfall goes through,” he said.
Post-fire debris flows killed 23 people in Montecito on Jan. 9, 2018, after the Thomas Fire scorched the mountains above the community, and caused major property damage in El Capitan Canyon campgrounds in 2017 due to burned hillsides from the previous year’s Sherpa Fire.
A flood advisory and high surf advisory were also in effect for Santa Barbara County on Monday.
More information about preparing for the storm, evacuations and signing up for alerts is available at ReadySBC.org.
An interactive map showing the latest evacuation zones is available at sbcoem.maps.arcgis.com.
For the latest Gaviota Coast weather forecast from the National Weather Service, go to forecast.weather.gov.
This story was originally published October 25, 2021 at 9:52 AM.