By midafternoon, there had been more than 200 serious accidents on Bay Area roads, according to the CHP and local police agencies.
To say the commute resembled molasses would be kind. Drives everywhere took nearly twice as long as normal, as people crept along on asphalt made slick by the accumulated water and motor oil that built up over the summer.
"Any time we have a big storm that comes in like this, we'll have these kinds of incidents. That's just the way it is," said Chase, who spent the day dashing from crash to crash. "The oil left from the summer comes up in the roadway, people don't slow down, and all you need is one person sliding into another and you get a chain reaction."
People who slogged along the roads to get to San Francisco International Airport found their flights delayed by as much as three hours because of the weather.
The National Weather Service posted a rare storm warning, predicting possible hurricane winds for San Francisco, San Pablo and Suisun bays and for the western part of the Sacramento-San Joaquin River Delta. The danger to boaters was so severe the U.S. Coast Guard advised mariners to keep their boats tied up at dock until Wednesday.
Winds between 50 to 65 mph are expected, and gusts of up to 75 mph are possible this afternoon, said forecaster Diana Henderson. Sustained winds of 74 mph are considered hurricane-force.
The wind predictions also caused the CHP to advise motorists to take extra care on all Bay Area bridges.
Rainfall totals, fed by the remnants of a Japanese typhoon, were impressive. The 2.18 inches that San Francisco received by 3 p.m. obliterated the previous mark for an Oct. 13 - 1.8 inches, set in 1962. It's also about 10 percent of what the city normally receives during an entire year.
"This rain is just sort of a blanket over everybody, and a fire hose in some places," Henderson said. "And we've got quite a bit more rain to come today."
The high-water mark by mid-afternoon was set in Ben Lomond in the Santa Cruz Mountains, which had received 8.2 inches. Elsewhere, 5.27 inches had fallen in San Rafael, 2.58 in Concord, 3.42 at the Oakland Museum and 1.74 in San Jose.