Marine Weather and Tide Forecast for Rancho Calaveras, CA

DISCUSSION

Today

A weather system will continue to bring scattered showers, light to locally moderate mountain snow, breezy winds and isolated thunderstorms through this evening. A Winter Weather Advisory remains in effect until 4 pm today for the northern Sierra and the southern Cascades and Lassen Park above 6000 feet. Expect mountain travel delays and chain controls at times. The latest probability of thunderstorms sits around 15-25% for this afternoon and evening across portions of the Valley and foothills. Main storm hazards include lightning, small hail, brief heavy rain and gusty winds. Breezy southerly winds are also expected across portions of the southern Sacramento Valley and northern San Joaquin Valley through late this afternoon and early evening, with gusts to around 20-25 mph.

Thursday through Friday

Dry conditions return Thursday through Friday as system drops down into SoCal and brief ridging develops over the area.
Seasonable temperatures are anticipated, with Valley and foothill highs generally in the upper 50s to mid 60s. Patchy morning fog may develop across portions of the southern Sacramento and northern San Joaquin valleys on Friday.

...Saturday through Mid-Next Week...

A potentially wetter and colder system arrives later this weekend through mid-next week, which could bring periods of moderate to heavy mountain snow, widespread rain and breezy southerly winds.
Precipitation will likely remain mainly over the mountains north of I-80 on Saturday, then gradually spreads across the area Sunday night into mid-next week. At this point, the heaviest precipitation appears to be Sunday night into early next week. NBM indicates a 50-85% probability of at least 1 inch of precipitation in the Valley, with a 60-85% probability of greater than 2 inches over the foothills and mountains through Wednesday morning.

NBM indicates a 65-90% probability of at least 2 feet of snow above 4000 feet through Wednesday morning, with potentially moderate to major travel impacts early next week. Snow levels start around 4500-5500 feet Sunday, falling to 3000-4500 feet on Monday-Tuesday (but there is a 10% chance it could be as low as 2500 feet by Tuesday morning). The colder air associated with this system means lower snow levels, possibly into the upper foothills by early next week. Model uncertainty remains regarding timing, exact snow levels and precipitation amounts. Stay tuned as more details become available!



AVIATION

VFR conditions with MVFR/IFR conditions next 24 hours due to weather system moving through the area. VCSH and VCTS at Valley TAF sites through 05z Thursday. BR conditions may develop at Sacramento Area TAF sites around 16z Thursday bringing a short period of MVFR conditions. Mountain snow through 05z Thursday; snow levels around 4500-5500 feet. Southerly wind gusts up to 30 knots through 02z Thursday, then north winds below 12 kts.

STO WATCHES/WARNINGS/ADVISORIES
Winter Weather Advisory until 4 PM PST this afternoon for West Slope Northern Sierra Nevada-Western Plumas County/Lassen Park.