After another day basking in sunny, unseasonably warm weather, residents and work crews turned their attention Wednesday to approaching back-to-back storms threatening to bring several inches of rain and possibly cause flooding and evacuations.
The first of the two weather systems — the weaker of the two — should reach the L.A. area after 6 p.m. Thursday, followed Friday morning with “a very dynamic storm,” said National Weather Service meteorologist Curt Kaplan.
The storms, accompanied by some disturbances, originated in the Gulf of Alaska and have been sucking up volumes of warm moisture from a so-call atmospheric river, said Kaplan, adding that Friday’s storm will be the biggest so far of the season, which starts Oct. 1.
Early estimates are that the region will receive 2-4 inches of rain in coastal and valley areas but between 4 and 8 inches in the mountains and foothills, forecasters said.
“Possible impacts due to potentially widespread heavy rain include flooding for urban areas and small streams, flash flooding with mud and debris flows, especially near and below recent burn areas, and rockslides along canyon walls,” warned an NWS statement.
“Travel delays are also likely due to reduced visibility and slick roads with water ponding on some roadways. Winter driving conditions are possible down to 6,000 feet late Friday into Saturday. Additionally, strong and potentially damaging southerly winds with this storm system may lead to downed trees and power lines.”
Kaplan said there could be rainfall rates of 1 inch an hour on Friday and added: “Stay away from canyons, burn areas, streams, washes, rivers, and dry river beds.”
Officials with the city of Duarte said they plan to declare a yellow alert at noon Thursday in neighborhoods below the Fish Fire burn area. The warning would require residents to keep streets clear of vehicles, trash bins and other objects that could obstruct emergency vehicles or be washed away in a flood. City officials said they could move to a red alert — meaning mandatory evacuations — by Friday night, depending how the storm develops.
Should such an alert be issued, an evacuation center would be established at the City Hall Community Center, 1600 Huntington Drive.
“At this point, the city is encouraging residents to plan for the most serious scenario, the red alert level requiring mandatory evacuations and the inability to return to your home until the closure is lifted,” according to a message posted on Duarte’s Facebook page. “Reminder, evacuated residents should always bring medicines and any other items they may need for a minimum 48-hour period.”
Similar issues could arise in Glendora and Azusa beneath the Colby Fire burn area. Azusa officials on Wednesday were distributing sandbags to residents at the City Yard, 809 N. Angeleno Ave.
Los Angeles County Public Works crews, meanwhile, worked frantically to clear debris from catch basins and storm drains in hopes of preventing flooding.
All the rain, however, was putting a dent in the drought and doing so in dramatic fashion. Normally, downtown L.A. would have received 8.96 inches of rain by this time of the year in the season that runs from October to April, but it already has had 16.25 inches, Kaplan said, “and there’s a whole lot more coming.”
— City News Service