Authorities on Friday pleaded with Glendora residents to heed evacuation orders as the second of two winter storms continued to douse the region with more rain than the area has seen in years, sending mud and debris down hillside streets.

Officials warned residents who chose to stay put -- as some have -- that if disaster struck they would have to hunker down and wait it out until it was safe for crews to come in and assist.

"As long as the mud is flowing, we cannot go into moving mud and debris and risk our personnel," Steve Martin of the Los Angeles County Fire Department said at a news conference. "Understand this: If there is mud coming down, fire personnel cannot get to you."

About 1,000 homes are in the section affected by the Colby fire last month in Azusa and Glendora are covered by the mandatory evacuation order, issued amid fears that mud and debris could inundate them.

Police are urging residents to leave, warning that they face "injury and/or death."

"There's a reason for these evacuations," Martin said, adding that the rains are "starting to intensify, the mud and debris are starting to come down more."

Glendora Police Chief Tim Staab echoed those sentiments.

"We understand that you want to stay and protect your home, but once that mud starts flowing, it can be too late to get out," he said.

Public works crews were busy throughout the day as streams of soupy mud poured onto streets, clogging drains and leaving piles of dirt and debris. The rain let up briefly after 11 a.m., providing a brief respite, but another round of heavy rain was expected to hit later in the day, forecaster warned.

"It's starting to flow .... Now's a good time," Staab said. "There's nothing you can do when the mud starts flowing."

Still, some residents were resolved to stay put. Among them was Dennis Madvig, 66, who said he decided not to evacuate from his Glendora home even though there appeared to be a mudslide threat nearby.

Early Friday morning he walked along Hicrest Road after mud and debris from the hills had rolled down. He said the road was built as a flood control channel after a major flood in the area more than four decades ago.

“This is nothing yet,” he said.

Glendora City Manager Chris Jeffers acknowledged the tough job of getting residents out of their homes.

"We know that a number of people have evacuated, but we are cognizant that a number of people are still in those neighborhoods," Jeffers said. "If you haven't left, this would be a good time."

Jeffers also said weather officials had just issued a flash-flood warning until about 1 p.m. for the area. Various weather warnings have been issued throughout the entire county and most of California, including wind alerts.

In Glendora, the evacuation orders apply to residents north of Sierra Madre Avenue between Yucca Ridge Road and Glendora Mountain Road.

In nearby Azusa, the evacuation order applies to residents on Ridge View Drive.

Glendora officials said Friday that they had began preparing for mudslides as soon as the Colby fire, which burned more than 1,900 acres in the San Gabriel Mountains, was extinguished in January.

However, they haven't had much time.