A pre-evacuation warning issued for Monday by Santa Barbara County emergency services officials was upgraded Tuesday evening to a recommended evacuation warning for residents below areas burned by the Thomas, Whittier and Sherpa fires.

The warning was primarily directed at residents of Goleta, Santa Barbara, Montecito, Summerland and Carpinteria, but officials said those in lower-risk areas throughout the county should also be prepared for the storm now expected to roll in later than anticipated Thursday night.

A flash flood watch was issued for those areas from 9 p.m. Thursday to 9 a.m. Friday.

The storm was initially expected to make landfall about 6 p.m. Thursday, but forecasters pushed that back to midnight, when the most intense rainfall is expected to begin and continue for up to six hours.

National Weather Service meteorologists said rain could fall at a rate of one-quarter to one-half of an inch per hour, which is less than initially predicted, but anticipated periods of heavy rain still could be enough to trigger mud and debris flows on slopes denuded by the fires.

Eric Boldt, warning meteorologist for the National Weather Service office in Oxnard, used a baseball analogy to describe the approaching rain.

“This will be a Minor League storm,” he said, not like the Major League storm that hit Jan. 9. “But we have to be careful, because even a Minor League player can hit one out of the park.”

Boldt said forecasters are not expecting any thunderstorms to develop.

“This is a wind-driven event,” he said, but he noted, “The Thomas fire area is a hotspot for heavy rain with its upslope condition.”

He said steady rain is forecast to begin shortly after midnight and continue for three to five hours, becoming heavy at times.

County Office of Emergency Management staff said people living below those burn areas are “strongly recommended to relocate” for their own safety due to a “high risk for loss of life and property.”

“We recommend you evacuate now,” Sheriff Bill Brown said late Wednesday afternoon. “If you do not evacuate, be prepared to evacuate at a moment’s notice.”

Brown said those with access and functional needs and those with large animals should leave immediately, and he also advised people living below he Alamo fire burn area to also prepare for evacuation.

If the storm remains at its currently forecast level or if the prediction calls for increased intensity, a mandatory evacuation order could be issued, Brown said.

“This is right on the cusp of (the level of) making a decision on evacuation,” Brown said, explaining the rate of rainfall that could trigger a debris flow is assumed to be one-half to 1 inch per hour.

He said that’s why officials are looking at potential mandatory evacuations.

The pre-evacuation advisory and recommended evacuation warning are part of the county’s new protocol for dealing with natural disasters, which was developed from lessons learned during the Thomas fire in December and especially the 1/9 Debris Flow that devastated Montecito.

Matt Pontes, who is directing recovery from the debris flow, said the advisory and warning were issued based on anticipated storm events.

“It’s possible we could get 2 inches from the storm, but that would be over the course of hours,” Pontes said, and that would likely not be intense enough to trigger debris flows, although brief periods of highly intense rainfall could.

He added the county has cleared mud and debris left by the Jan. 9 slides from all the roadways, 92 percent of the debris basins and 74 percent of the creek channels.

“We’re well ahead of schedule on cleaning those channels,” added Rob Lewin, director of the County Office of Emergency Management.

In response to the increased risk, Santa Barbara County Fire Department will increase staffing levels at its stations from 8 a.m. Thursday to 8 a.m. Friday, said Capt. Dave Zaniboni, department spokesman.

The step-up will add hand crews, an urban search and rescue team and a swift water rescue team along with fire engines, bulldozers, excavators and helicopters that can respond to emergencies throughout the county, Zaniboni said.

He added that staffing will also be increased at fire departments in Santa Maria, Lompoc, Vandenberg Air Force Base, Santa Barbara, Montecito and Carpinteria/Summerland.

Lewin said a state Office of Emergency Services water rescue team is scheduled to arrive Thursday morning from out of the area.

As part of preparations for Thursday’s storm, an American Red Cross of the Pacific Coast evacuation center opened at noon Wednesday at the Earl Warren Showgrounds on Calle Real in Santa Barbara, where an evacuation center for large animals was also set up.

Red Cross officials said the organization was prepared to transition to a full sheltering operation if necessary, and additional volunteers at locations throughout the region were on alert to respond if severe weather continues to move through.

John Lindsey, meteorologist for Pacific Gas and Electric Co. at Diablo Canyon Power Plant, said the higher peaks of the Santa Lucia Mountains may be dusted white from this storm, as snow levels could drop to 3,000 feet along the Central Coast.

The area will get a rain break as high pressure will produce Santa Lucia winds and dry conditions Sunday through Tuesday, Lindsey said.

But then another low-pressure system is expected to arrive, bringing southerly winds and rain Wednesday and Thursday.

County Office of Emeregency Management officials initially issued the pre-evacuation warning for Monday’s storm, which turned out to be less intense than anticipated. In fact, neither Goleta nor Santa Barbara recorded any rainfall.

The highest totals in hundredths of an inch included 0.11 in Cuyama, 0.12 at Cachuma Lake’s Bradley Dam, 0.14 in Lompoc, 0.15 at Sisquoc, 0.17 in Los Alamos and 0.19 in Santa Maria.

Other totals from around the area in hundredths of an inch were 0.01 in Carpinteria, 0.05 at Gibraltar Dam, 0.05 at San Marcos Pass, 0.06 in Buellton and 0.06 in Santa Ynez.