A warmer storm system brings widespread precipitation today. Significant mountain travel impacts are expected with periods of heavy snow and gusty winds. Drier conditions return later Sunday into early next week.

Heavy snow is expected in the mountains through Sunday morning. Snow-covered roads, reduced visibility, travel delays, chain controls and road closures are all possible. Check the forecast/roads before you travel, especially to the mountains.

Discussion

Rain amounts of 0.30 to 1.50 inches are forecast across the Valley (heaviest in the northern Sacramento Valley), with 1 to 2.5 inches in the foothills through tonight. Slick roads and longer than normal travel times are expected for those aforementioned areas today.

A weather system will bring light to moderate precipitation today, with the highest Valley amounts from Sacramento northward. Be prepared for slick roads and a longer than normal commute.

As far as winter weather, heavy mountain snow is expected, with the heaviest amounts above 6000 feet in the Sierra Nevada. The Winter Storm Warning remains in effect for Western Plumas/Lassen area and for the northern Sierra through tonight for 1-2 feet of snow above 5000 feet.

Snow rates of 1-2" per hour, heaviest between 11 AM and 11 PM PST today

High resolution guidance shows snow rates of 1-2 inches per hour, with the heaviest expected between 11 AM and 11 PM PST today. Snow covered roads, chain controls, travel delays and reduced visibility are all likely, with road closures possible. For portions of the Shasta County mountains, Coast Range and Burney Basin, expect 4 to 8 inches of snow above 3000 feet through this evening.

A warmer system moves in tonight through Saturday, bringing major travel impacts from heavy mountain snow above 6000 feet. Expect difficult travel conditions, chain controls, & reductions in visibility at times.

Snow levels will generally be around 4500-6500 feet today, locally down to 3000 feet in some parts of Shasta County. Mountain travel is discouraged through tonight. Travelers should always be checking the forecast and roads before heading out the door!

Gusty southerly winds are expected this afternoon and evening. Gusts up to 35-40 mph are possible across portions of the eastern side of the Sacramento Valley. Expect difficult driving conditions for high profile vehicles, downed tree branches and local power outages.

Gusty southerly winds are also forecast with this system today. Winds will be increasing through the day, strongest in the afternoon and evening hours. The NBM advertises a 40 to 70 percent probability of 40 mph gusts or greater today, mainly in the northern/central Sacramento Valley, and a 65 to 95 percent probability for the same threshold in the mountains where winds are expected to be the strongest.

Gusty southerly winds will develop this afternoon and evening, a Wind Advisory is in effect for the northern/central Sacramento Valley east of I-5.

The Wind Advisory remains in effect from this afternoon through this evening to address those gusty southerly winds, and potential impacts such as unsecured objects blowing around, downed tree limbs or branches, and local power outages.

Precipitation is expected to taper off overnight into Sunday, with just a few lingering showers/snow showers possible mainly in the morning.

Dry weather looks to prevail for the rest of the weekend and into early next week as the system exits the region and an upper levelridge builds in, with perhaps some foggy mornings in the Valley.

Extended Discussion (Wednesday through Saturday)

Ensemble guidance and cluster analysis indicate a ridging pattern setting up over the region over much of the extended forecast period, allowing for drier conditions to prevail, as well as a slight warming trend from mid to late week. Daytime high temperatures in the Valley are expected to be in the upper 50s to 60s for much of this timeframe, which will be trending above normal for mid January climatology.

The National Blend of Models (NBM) keeps some chances for precipitation on Wednesday, mainly in the morning, as a weak system exits the region, and then again late Friday into Saturday as another trough approaches the West Coast. There is still some uncertainty with this to be sure to stay up to date with the latest forecast.