Marine Weather and Tide Forecast for San Anselmo, CA

SHORT TERM
Issued at 115 AM PST Fri Feb 6 2026 (Today through Saturday)

Recent KMUX imagery shows scattered returns moving northward over the Central Coast this morning. This is in response to mid level moisture moving northward along a passing upper level low that will travel southeastward over the ocean down the Central Coast today. No measurable precipitation is expected, but given that KMUX is getting some echos between 20-30 dBz, went ahead and threw in mention of isolated sprinkles down the Big Sur coast for this morning. Regardless, the vast majority of the area will remain dry, with only an increase in cloud cover today. However, that increased cloud cover will help minimize any valley fog this morning. Temperatures are expected to still climb just slightly above seasonal norms today, but with the increased cloud cover and cooler air moving in with the low, it should feel a little cooler compared to recently.

Weak ridging is expected to return tonight and into Saturday.
This should help clear some of the skies out tonight which may allow for radiational fog development in valley locations.
Otherwise, the cooler airmass should provide similar temperatures on Saturday with highs in the 60s and upper 50s/low 60s along the coastline.

LONG TERM
Issued at 115 AM PST Fri Feb 6 2026 (Saturday Night through Thursday)

The pattern begins to shift on Sunday. While the weak ridge will remain in place over Central California during the day on Sunday, a longwave trough in the northeast Pacific will begin to make it slow movement southward down the British Columbia coastline. This wave will eventually send a couple of shorter waves that can provide additional chances for rain through the middle of next week.

The first weak short wave is expected to eject away from this parent wave and move over the Pacific northwest Sunday evening.
With the majority of ensemble members continuing to highlight the higher QPF in the Pacific northwest, blended PoPs were adjusted down for Sunday evening to confine the highest chances (20 to 40 percent) to the North Bay. This left just a 15 to 20 percent chance that light rain makes it to the city of San Francisco with a less than 15 percent chance it makes it to the South Bay (and even then it probably would not reach the South Bay until around or after midnight). Regardless, the amount of rain is expected to be only a couple hundredths in the North Bay and less to the south.

Models are projecting a more stout shortwave trough to descend down the coastline Tuesday through Wednesday. Cluster analysis is highlighting that models are still struggling with the depth and track of the upper level trough. However, with increased moisture and better forcing, it looks like a better chance for rain across the forecast area. Higher coastal elevations could see over a quarter of an inch of rain, but inland areas could be impacted by the rain shadow and see much less. Lastly, a cooler air mass aloft will accompany this trough, allowing for temperatures next week to return to more seasonable norms.

Once that trough passes there could be a break in the precip toward the end of next week. However, models are keeping an active pattern aloft which may bring another rainy system to the area next weekend. It is still a little too early for the details, but something to certainly keep an eye on.

AVIATION
(12Z TAFS)
Issued at 447 AM PST Fri Feb 6 2026

A combination of high and mid level clouds, a few sprinkles, virga aloft with a 500 mb trough to our west-southwest, including likely isolated very weak negative (downward directed) instability due to evaporative cooling of showers in dry sub-cloud air resulting in weak disruptive winds reaching land and/or sea surface e.g. KMRY had a sudden, temporary southwest wind to 15 mph at midnight - are all adding up to greatly limiting fog patches. All of the described is also limiting and potentially mixing out much if not all stratus clouds over our coastal waters. METAR observations heavily lean VFR though there this the occasional IFR reported e.g. at KHAF and KLVK.
Hazy to haze conditions in the Bay Area are reducing surface visibility, including slant range visibility mainly at sunrise and sunset.

Conditions today favor VFR over the forecast area with exception of MVFR surface visibilities at times in the Bay Area due to haze.
Another potential component in the mix today is the potential of a southerly wind reversal reaching the north Central Coast, however the NAM, HRRR model output show e.g. the SMX-SFO pressure gradient weakens by late morning and afternoon, detrimental to a southerly wind reversal (advection of stratus). Elsewhere today with the departure of the high and mid clouds, there'll be a greater amount of incoming solar radiation and diurnal mixing including over the coastal waters where stratus will likely mix out under these conditions. Also, sea surface temps are running 3-4F above Feb normal and coastal buoy data so far show little if any evidence of cooler air temps relative to sea surface temps which is unfavorable for stratus/fog development. The NAM does however show a shallow, cooler air mass arriving tonight into the Bay Area, this coupled to nocturnal radiative cooling will increase the probability of stratus /MVFR-IFR/ arriving on onshore winds tonight and Saturday morning. In the world of stratus and fog prediction, tonight and tomorrow is a long time from now, a lot as in this case depends on the level of mixing today as to how well the stratus holds together before any benefit from cool air advection and/or radiative cooling post sunset tonight. Currently the 12z TAFs are a low to moderate confidence forecast with MVFR-IFR ceilings generally introduced for tonight and Saturday morning.

Vicinity of SFO...Near high confidence VFR today into the evening, then there is an increasing probability of stratus /MVFR/ arriving beginning 11z Saturday with the ceiling potentially continuing through 18z Saturday before mixing out. Northwest wind 5 to 10 knots today becoming westerly near 5 knots tonight and light and variable Saturday morning.

SFO Bridge Approach...Slant range visibility potentially lower at sunrise and sunset due to hazy conditions. These conditions may improve during the afternoon depending if a westerly wind can strengthen and bring in a fresher sea breeze, the cooler air also deepening and weakening the marine layer. Otherwise similar to SFO.

Vicinity of SJC and OAK...Here too, the slant range visibility may be potentially lower at sunrise and sunset due to hazy conditions. If SFO Bridge Approach sees improvement then here too there may be improvement during the afternoon. Generally low to moderate confidence on stratus /MVFR/ arriving tonight and Saturday morning.

Monterey Bay Terminals...Near high confidence VFR today into the early to mid evening before stratus /MVFR-IFR/ arrives here. It does not look favorable for a southerly wind reversal (and stratus advection) today based on what was described above, however of course the caveat is need to monitor SMX-SFO, SBA-SFO pressure gradients, winds and satellite closely during the day. With the onset of nocturnal cooling and near surface cool air advection, stratus development has a better chance to arrive here; the 12z TAFs advertise timing of IFR by midnight tonight. Light southeast winds shift to onshore 5 to 10 knots in the afternoon then light and variable tonight and early Saturday.

MARINE
(Today through Wednesday)
Issued at 247 AM PST Fri Feb 6 2026

A shallow cool air mass drifting over the coastal waters will result in light to gentle northwest winds today in to Saturday.
Hazardous seas over the coastal waters today continues tonight and early Saturday morning before seas diminish. A cold front moves southeastward over the coastal waters and bays Sunday night resulting in an increase in northwesterly winds Monday and Tuesday.

BEACHES
Issued at 247 AM PST Fri Feb 6 2026

A High Surf Advisory will be in effect beginning 4 AM PST today at all Pacific Coast beaches, the High Surf Advisory continues through 9 PM Saturday. Westerly swell will bring an increased risk for sneaker waves and strong rip currents with breaking waves 17 to 22 feet.

Remember to stay off of jetties, piers, rocks, and other waterside infrastructure, remain out of the water, and never turn your back on the ocean!

MTR WATCHES/WARNINGS/ADVISORIES
CA...Beach Hazards Statement until 4 AM PST early this morning for CAZ006-505-509-529-530.

High Surf Advisory until 9 PM PST Saturday for CAZ006-505-509- 529-530.

PZ...Small Craft Advisory until 3 AM PST Saturday for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM-Pt Pinos to Pt Piedras Blancas 0- 10 nm.

Small Craft Advisory until 9 PM PST this evening for Pt Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory until 9 AM PST Saturday for Pigeon Pt to Pt Pinos 10-60 NM.