A second morning flight — this one to Seattle — was also delayed because the same plane that flies to Los Angeles is typically used for the Seattle journey, Stout said. Alaska Airlines was able to bring in a backup plane to take Seattle-bound passengers to their destination about an hour behind schedule, he said.

Official lows in Healdsburg hit 24 degrees, while lows in Petaluma hit 19 degrees in Petaluma, 30 degrees in Pt. Reyes, 31 degrees in Bodega Bay and 24 degrees in Sebastopol.

In Napa County, Calistoga's low was 30 degrees while down valley in downtown Napa, it reached 24 degrees. and in parts of Graton and Petaluma it got down to 19 degrees, said Benjamin.

The relative warm spots early Monday were in the areas of Occidental and Bodega Bay, with 31 degrees, and Cazadero at 32 degrees.

"If you want to call that warm ..." said Benjamin.

The morning lows were falling 15-20 degrees below normal.

Despite the chilly temperatures, no records were broken Monday.

"Back in 1972 we had some really really cold temperatures," he said.

Santa Rosa that Dec. 9, 1972 morning dipped to 16 degrees.

The weather service issued a freeze warning through 9 a.m. today and another one to start at 10 p.m. tonight. Yet another such warning is probable for Tuesday.

The forecast for the next week is cold and dry.

Morning lows were expected to stay in the mid 20s in the Santa Rosa area on Tuesday.

The Bay Area air quality officials issued the seventh winter Spare the Air alert for the season for Tuesday because the cold, stagnant weather keeps air pollution at dangerously high levels, according to the agency.

Fireplaces, wood stoves and other wood-burning structures must again remain dormant for 24 hours starting at midnight.

Homes where wood stoves or fireplaces are the only sources of heat are exempt from the ban.

By Wednesday, morning lows should reach about 30 and get to the high 30s by the end of the weekend.

Monday's high in Santa Rosa was only due to get to about 50 degrees. A gradual warming trend by a degree or two each day should get to almost 60 degrees by Sunday.

Average temperatures for Santa Rosa for this day are 37 and 57.

Meanwhile, no rain is expected for at least a week.

The CHP reported no major traffic problems Monday. Icy road reports were few and included some major routes in the Sonoma Valley, including stretches Watmaugh Road, Arnold Drive and Highway 116.

Those areas were being treated to eliminate the ice, said the CHP.