Freeze Watch issued December 3 at 12:45PM PST expiring December 6 at 9:00AM PST by NWS Sacramento CA
Areas Affected: Central Sacramento Valley; Carquinez Strait and Delta; Southern Sacramento Valley
• A cold dry airmass filtering over the region will result in the possibility of freezing morning temperatures in the valley.
• Tuesday morning freezing temperatures will be possible in the San Joaquin Valley and over Southern Lake County. Lighter winds Tuesday night will allow for a greater area to potentially reach the freezing mark by Wednesday morning.
• The National Weather Service in Sacramento has issued a Freeze Watch, which is in effect from late Tuesday night through Wednesday morning.
* TEMPERATURE…Coldest lows ranging from 28 to 32.
* IMPACTS…Freezing temperatures can damage or kill plants that are sensitive to cold. Please check on the elderly and make sure your animals have a warm shelter.
•A Freeze Watch means sub-freezing temperatures are possible.
•These conditions could kill crops and other sensitive vegetation.
A weak frontal band dropping southeastward over the northern Sierra this morning is currently dropping snow down to about the 5000 foot elevation. About an inch or two of snow has fallen so far and Caltrans sites are reporting chain controls on interstate 80 above 5000 feet. Snow levels will continue to fall behind the frontal band this morning, possibly down to the 3000 to 4000 foot level, but precipitation amounts will be waning by mid morning. Expect about 1 or 2 more inches of additional snowfall will be possible before the front moves through and precipitation ends. Precipitation has mainly ended in the valley this morning where only a couple of hundredths of an inch of rainfall fell. Some fog has formed in the central valley this morning but lingering cloud cover will hopefully keep it from becoming dense. By this afternoon, only a few lingering showers are expected over the Sierra crest with clearing skies elsewhere.
Behind the front tonight into Monday a northerly surface gradient will increase as upper flow becomes northerly. This will produce breezy to locally windy conditions most locations on Monday. At this time, wind speed forecasts in the valley remain a little under advisory speeds but surface gradients and upper support for north winds look good so winds could come in higher than forecast.
Cold air advecting into the region behind the front will lead to colder nighttime temperatures next week but daytime highs will warm as the airmass warms up under a building ridge. The coldest mornings look like they will be on Tuesday and Wednesday under lighter wind conditions and some locations in the valley could drop to around freezing. Otherwise a dry weather pattern with slightly above normal daytime temperatures will continue through mid week under anomalously strong high pressure.