Marine Weather and Tide Forecast for Napa, CA

UPDATE
Issued at 910 AM PST Fri Nov 14 2025

The short term forecast is in good shape with the only minor change being to update PoPs for ongoing trends. An upper low, currently churning just offshore, will continue to send ribbons of moist ascent across the area. This will encourage showers through at least late afternoon. Instability is greatest offshore and at this time, I'm anticipating largely showers, though a rumble of thunder cannot be completely ruled out. PoPs range from near 10% across the North Bay to around 40% across the Central Coast.
Additional rainfall amounts through this afternoon should peak near around 0.10" across the higher terrain of the Santa Lucia and Diablo Ranges, with largely up to 0.05" elsewhere across the Central Coast and East Bay. The afternoon forecast update will feature a closer examination of the active weather pattern this weekend and into next week.

SHORT TERM
Issued at 204 AM PST Fri Nov 14 2025 (Today and tonight)

Rain has largely stopped across the Bay Area with only a few scattered showers remaining over the Central Coast and South Bay.
The North Bay Mountains, Santa Cruz Mountains, and Santa Lucia Range saw the highest precipitation totals between 4"-6". In the Santa Lucia Range, the Mining Ridge site (MNRC1) was our big winner and saw a total of 6.5" over the last 24 hours. Elsewhere, the lower elevations of the North Bay, East Bay, and San Francisco Peninsula saw 1-2.5", the South Bay saw 1-2", and the Central Coast saw between 0.5-2". A look at the California Nevada River Forecast Center (CNRFC) shows that nearly every site in the Bay Area and Monterey/San Benito is running anywhere from 100% to over 200% of normal for the water year so far. A promising start to our water year so far!

The upper level low to our northwest is expected to weaken, gradually move southward, and become a cut-off low offshore of Southern California by later today. This will continue to bring light rain across the region with totals ranging from a few hundredths of an inch to around a tenth of an inch. There is a low (5%) chance of thunderstorms across the Central Coast and South Bay late this morning and afternoon. NAM guidance shows at least a few hundred J/kg of most unstable CAPE across the South Bay and Central Coast today but the 700-500 mb lapse rates (the change in temperature over the 700 mb to 500 mb layer) don't look that impressive. Lapse rates are forecast to be in the 6-7 C/km range which suggests a more stable to slightly conditionally unstable environment. Morning low temperatures are feeling a bit chillier with lows in the mid 40s to low 50s expected today. Temperatures across the higher elevations of the Central Coast will be even cooler, with lows potentially dropping into the upper 30s to low 40s. The combination of light rain and cooler mornings may result in a chillier than normal early morning commute so make sure to dress adequately. High temperatures will be in the low to mid 60s across the region on Friday with cooler temperatures in the upper 40s to 50s expected across the highest mountain peaks.

LONG TERM
Issued at 204 AM PST Fri Nov 14 2025 (Saturday through Thursday)

Rainy weather continues on Saturday as the cut-off low off of southern California moves inland. This will bring a surge of into Southern California which will gradually move northward into the Central Coast and result in an additional 0.5-1.5" of rain. While the bulk of the rain on Saturday will be over the Central Coast, portions of the South Bay and Santa Cruz County will see up to 0.5" while the rest of the Bay Area sees between a few hundredths to 0.25" of rain. This cut-off low will be ejected eastward by an incoming deep, upper level trough Sunday into Monday. This system will bring widespread rain to the Bay Area and Central Coast Sunday into Monday. The North Bay looks to see between 0.5-1.5", the Santa Cruz Mountains and Santa Lucia Range will see between 0.5-1.0", and the rest of the Bay Area and Central Coast will generally see around 0.5-0.75". Gustier winds return Sunday into Monday but do not look to be as widespread as they were earlier this week. We briefly manage to dry out Monday night through Wednesday morning before another potential system rolls through mid to late next week.

While rain is the eyecatcher of the forecast, temperatures will noticeably cool (both highs and lows) starting Sunday. Saturday will be the warmest day through the remainder of the long term forecast with highs in the mid to upper 60s across the Bay Area and upper 50s to low 60s for the Central Coast. As our upcoming Sunday to Monday system brings widespread rain, it will also bring in a much cooler airmass. Guidance shows 850 mb temperatures around 8-9C on Saturday dropping to 5-6C by Sunday and 3-4C by Monday/Tuesday. This will keep our high temperatures in the mid 50s to low 60s for much of the next week. Morning low temperatures will drop into the low to mid 40s across the lower elevations and into the mid to upper 30s across the higher elevations. Tuesday and Wednesday mornings are currently the coldest of the forecast period so anyone outside early in the morning will want to bundle up. With the combination of cooler temperatures and a potential system mid to late next week, the NBM is highlighting a low potential for snow on the highest peaks of the Santa Lucia and Gabilan Ranges next week. Hopefully you aren't tired of cooler and wetter weather already as the CPC indicates below normal temperatures and above normal precipitation is likely to continue through at least early December. Remember to stay up to date on the forecast as our next few systems arrive this week.

AVIATION
(12Z TAFS)
Issued at 313 AM PST Fri Nov 14 2025

The low pressure center and associated cold front have moved into Southern California, leaving a mixture of isolated mist and fog, with widespread low, mid, and high level clouds across the Bay Area and Central Coast. A few isolated showers remain this morning, but most terminals should stay dry today. Winds will be much lighter than yesterday, and the lower clouds will start to clear through the afternoon.

Vicinity of SFO...There is only a slight and decreasing chance for low ceilings this morning, though with nearly saturated air and light winds at the surface, we could still be in for a sunrise surprise of reduced visibility. Fortunately a blanket of high clouds is reducing radiational cooling and suppressing this chance. Otherwise winds will be light and variable through the morning before a gentle onshore breeze becomes established through the afternoon. There is another slight chance for ceilings Saturday morning, but the most likely outcome is VFR conditions through the TAF period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...The best chance for rain is at the Monterey Bay Terminals this morning, but any showers should be light and brief. Otherwise VFR conditions are expected with a steady supply of mid level clouds through the TAF period.

MARINE
(Today through Wednesday)
Issued at 910 AM PST Fri Nov 14 2025

Buoys are reporting a light southerly breeze with very high westerly swell up to 15 feet/15 seconds. The swell will gradually subside through the day with more favorable conditions through the weekend. A fresh to strong northerly breeze arrives Monday, building rough seas across the inner waters and very rough seas in the outer waters. Conditions will improve through midweek.

BEACHES
Issued at 124 AM PST Thu Nov 13 2025

A Beach Hazards Statement is in effect through Friday evening.
Long period westerly swell will result in an increased risk for sneaker waves and rip currents. Breaking waves of 15 to 20 feet are expected. Sneaker waves can unexpectedly run significantly farther up the beach than normal, including over rocks and jetties. Rip currents are typically more frequent and stronger in the vicinity of jetties, inlets, and piers.

MTR WATCHES/WARNINGS/ADVISORIES
CA...Beach Hazards Statement until 9 PM PST this evening for CAZ006- 505-509-529-530.

PZ...Small Craft Advisory until 3 PM PST this afternoon for Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm.

Small Craft Advisory until 9 PM PST this evening for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm.

Small Craft Advisory from 3 PM to 9 PM PST Saturday for Pt Arena to Pt Reyes 10-60 NM.