They might be skiing till July 4 in the Sierras. It could take longer than that for some San Francisco Bay Area residents to put right the damage done by what is being called the worst rainstorm ever recorded in the area.
The latest in a succession of storms that have swept across northern and central California since early November moved in early Sunday evening (Jan. 4). By the time the rain tapered off early Tuesday morning, many rainfall records for the Bay Area had been washed away, an estimated 7,000-plus people had been forced from their homes by flooding or mud slides, most of Sonoma and Marin Counties north of San Francisco were cut off from the city, and up to five feet of new snow had been dumped on the higher elevations of the Sierras in the Lake Tahoe area.
Seven fatalities in northern California were attributed to the storm and property damage is expected to amount to several million dollars. The heavy weather also led to widespread business disruptions and personal inconveniences. Many people employed in San Francisco could not get to work Monday or Tuesday; others who did get in Monday morning were stranded in the city. Downtown hotels put up many at reduced room rates, mostly half-price; the Red Cross and other charitable organizations were furnishing food and shelter.
From Sebastapol in Sonoma County north of San Francisco to Santa Cruz, some 50 miles south on the coast, there was extensive flooding. Most schools were shut down Monday and Tuesday.
Flooding problems stretched east into Alameda and Contra Costa Counties. In Richmond, on the eastern shore of San Francisco Bay, Amtrak's San Francisco Zephyr was derailed by washed-out track; several passengers were injured, none seriously.
There were many dramatic and costly effects of the storm, but the most disruptive was a mudslide in Marin County, just north of the Golden Gate Bridge. The mud and debris (a highway patrol officer said a ''whole mountain came down'') completely blocked US 101 near Sausalito. Officials said it would take at least 36 hours to restore traffic on the only major commuting route to the city from Sonoma and Marin Counties.
After two years of subnormal rainfall, nature has overcompensated in the 1981 -82 ''wet season.'' Since early November, one moisture-laden storm system after another has swept in from the Pacific. The ground has been thoroughly soaked for weeks, the ski season started early around Lake Tahoe, and some say the San Francisco 49ers parlayed a sodden home football field (and more than a little talent) into the best record in professional football this season.
There is some confusion as to whether San Francisco has a new 24-hour rainfall record. The National Weather Service, which takes its measurments at San Francisco International Airport, recorded an official 2.54 inches of rain in 24 hours. The record is 4.67 inches, set in January 1881. But independent meteorologists in the city measured 6.25 inches in 24 hours - 10 p.m. Sunday to 10 p.m. Monday.
Kentfield in Marin County had 12 inches of rain in 24 hours. Santa Cruz - 40 miles south of San Francisco on the shore - had 8.25 inches.
Of more long-term significance is the obvious fact that after two years of near-drought, northern and central California are assured of full fresh-water reservoirs next spring. A great deal of the water received in recent storms, particularly Monday's, could not be conserved. But with the best snowpack in many years in the mountains, there will be plenty of spring runoff that can be stored for later use.