A sprinkling of rain Friday did little to stop this month from likely going down as the second driest December on record — but it was enough to play havoc with drivers.

Between 6 a.m. and 1:30 p.m., CHP officers responded to eight accidents on local highways, nearly twice the typical amount for a full 24-hour period.

Nearly all the accidents were weather related, including a five-car rear-ender that blocked northbound Highway 101 for 30 minutes.

"When you have a dry month and then finally get a little bit of rain, people seem to forget they need to slow down," Officer Jon Sloat said.

Certainly there hasn't been much chance to practice wet-weather driving this winter.

As of Friday, just .09 inches of rain had fallen in downtown Santa Rosa, the second driest December in more than 80 years.

Aside from 1989, when no rainfall fell in Santa Rosa, there's not a December on record that comes close to matching 2011 for lack of precipitation.

In 1956, the third driest December, 0.38 inches fell in Santa Rosa. Friday's rain, measured as a trace, did little to close the gap.

Blame lies with a high-pressure system that's been sitting over the region for weeks, forcing approaching weather patterns around it, said Diana Henderson of the National Weather Service.

That blocking system appears to eroding, however, increasing chances for winter rains in the New Year, which perhaps nobody would like to see more than the county's cattle ranchers.

On some ranches, arid conditions and cold weather have stunted grasses used for grazing and endangered silage crops for spring feeding.

Cheryl LaFranchi, who has about 400 cows on 4,100 acres in Knights Valley, said she just paid about $12,000 for two loads of hay she wouldn't have needed in a wetter year.

"It's getting a little scary," said Doug Beretta, an organic dairy farmer near Santa Rosa.

Normally by December, his cows have relocated to a barn to avoid getting mired in muck or causing manure-related water-run off problems, he said.

It's the first December he can remember when they've remained in pasture, an image that's even rarer given the dust that rises when the animals gather for feed.

"That's not supposed to happen in December," he said.

Still he said it's too soon to really worry. A wet winter should take care of the problem, he said.

"If we get rains in January or February, we are probably going to be okay," he said.

Grapegrowers have less to be concerned about. As long as rains come before bud break starting in March, the now dormant vines should be in good shape, said Nick Frey, president of the Sonoma County Winegrape Commission.