Emergency responders keep close eye on Montecito as storm intensifies in Santa Barbara County

Steady rainfall across Santa Barbara County on Wednesday was causing roadway flooding and fallen trees as emergency responders kept their eyes on recent burn areas, especially the Montecito and Carpinteria communities below the Thomas Fire.

Responders were staged throughout Santa Barbara County's South Coast in case of storm-related emergencies caused by flooding or debris flows, which ​are predicted in the latest weather forecast.

Mandatory evacuation orders were in effect Wednesday for western Goleta Valley, Montecito, Summerland and Carpinteria areas, affecting about 30,000 people.

Areas on the South Coast were receiving the 1/2-inch-per-hour rainfall rates that are the minimal threshold for causing debris flows, according to the National Weather Service.

The storm system, fueled by an "atmospheric river" of sub-tropic moisture off the coast, is expected to drop light rain on the region with periods of moderate-to-heavy rainfall, said Stuart Seto, a meteorologist with the National Weather Service in Oxnard.

Authorities were watching for minor debris flows as of Wednesday morning, he said, and there has been reported minor flooding throughout the county.

The storm is expected to continue through Thursday, with more potential for debris-flow-causing rainfall later Wednesday into Thursday morning for Santa Barbara County.

A flash flood watch is in effect through 5 p.m. Thursday.

“Public safety officials are referring to this moment as a ‘half time’ for this storm because we are seeing a slight lull,” Santa Barbara County said mid-morning. ”Steady and higher intensity of rainfall is expected later Wednesday into Thursday. Stay safe and remain vigilant!”

United canceled multiple flights out of the Santa Barbara Airport on Wednesday morning, and the Amtrak Pacific Surfliner reported a train delayed in Carpinteria as of 1:45 p.m. while Union Pacific crews removed a mudslide near the tracks.

There were multiple vehicle accidents throughout Santa Barbara County, including jack-knifed semi trucks, but no injuries were reported.

The California Highway Patrol was prepared to close Highway 101, between Santa Barbara and Carpinteria, if necessary, and had closed Highway 33 north of Ojai in Ventura County due to a debris flow Wednesday morning.

This story was originally published March 21, 2018 at 6:42 PM with the headline "Emergency responders keep close eye on Montecito as storm intensifies in Santa Barbara County."