Marine Weather and Tide Forecast for Los Altos, CA

SHORT TERM
Issued at 1135 PM PDT Sun Mar 22 2026 (Tonight through Tuesday)

Upper level ridging gradually rebuilds on Monday with above normal temperatures continuing. High temperatures will be in the upper 70s to low 80s across the interior with 60s to 70s along the coastline.
The warmest areas will be in the interior Central Coast where high temperatures will reach the mid to upper 80s. High temperatures are running 10-15 degrees above normal which is cooler than the 20-30 degrees above normal that we saw last week. One of the reasons for this difference is that the upper level ridge is weaker with heights peaking around 5850 meters over the Bay Area (compared to over 5900 meters we saw last week). The center of the ridge is located to our south over the desert southwest. We can expect temperatures to cool down overnight with morning lows on Monday and Tuesday in the upper 40s to mid 50s. Minor HeatRisk is forecast across the region through the entire week which primarily impacts those who are extremely sensitive to heat. Guidance is showing some potential for a shallow 500-750 ft marine layer developing tonight but confidence is on the lower end given the rebuilding ridge.

LONG TERM
Issued at 1135 PM PDT Sun Mar 22 2026 (Tuesday night through next Sunday)

Above normal temperatures continue through the Long Term forecast with some potential for rain to return end of March/start of April.
Upper level ridging persists through at least Tuesday with highs in the upper 70s to low 80s across the interior, 60s to 70s along the coast, and upper 80s to low 90s across the interior Central Coast.
Heading into Wednesday, the forecast gets a little more interesting. Both the Euro and the GFS show a cut-off upper level low over the Pacific being reabsorbed into the large scale pattern and moving through southern CA as a shortwave trough. This displaces center of the upper level ridge further eastward (vicinity of AZ/NM) and coincides with the passage of a weak surface based cold front. Temperatures will drop 3-5 degrees Wednesday and Thursday with highs largely in the mid to upper 70s across the interior, 60s along the coast, and mid 80s across the interior Central Coast. A look at the Precipitable Water forecast shows PWAT values between 0.8-0.9" across the North Bay before the front falls apart as it moves south of the Golden Gate. Don't go getting to hopeful for rain just yet though. Models aren't showing any rain associated with this frontal passage, but, it may be enough moisture to generate some coastal drizzle. WRF guidance shows a shallow marine layer redeveloping on Wednesday which may increase coastal drizzle odds for the North Bay. Gusty winds briefly return Wednesday as frontal passage occurs but the windiest conditions largely stay over the marine environment and the higher elevations. Upper level ridging makes an effort to redevelop late week but, with the center of the ridge displaced farther east, we are only looking at a temperature increase of 2-3 degrees Friday into the weekend.

For any rain fans out there, long range guidance shows a deep upper level trough moving onshore at the end of March/beginning of April.
The current forecast shows precipitation chances increasing as early as March 30th but this is likely to be pushed backwards in time.
Cluster guidance maintains ridging influence over the West Coast through at least the 31st with troughing becoming more likely starting April 1st. The clusters are not fully in agreement on this scenario yet either with 3 out of 5 showing troughing, 1 showing more zonal flow, and 1 showing ridging over the West Coast on April 1st. While there is uncertainty as to when precisely the trough will arrive, models are in agreement that rain will in fact return at the beginning of April. It is worth mentioning that nearly all the Euro and GFS ensembles are picking up on light rain returning in the 4/1- 4/3 timeframe. Do the current ensemble rain amounts look impressive? Not terribly. Most models are showing around 0.5" with only a handful showing over 1" to 1.5" of precipitation. Still, it's better than nothing especially as the rainy season is winding down. The CPC maintains the potential for above normal precipitation across our CWA through April 5th with a return to below normal precipitation expected after that in the Weeks 3-4 outlook.

AVIATION
(06Z TAFS)
Issued at 933 PM PDT Sun Mar 22 2026

Currently VFR at all terminals with high clouds streaming in overhead. High confidence on VFR through the TAF period. Low probability for sub-VFR conditions returning to the terminals tonight with the relatively greatest potential at HAF, MRY, and SNS. Onshore winds will prevail. Haze will reduce slant range visibilities.

Vicinity of SFO...Currently VFR with westerly flow. High confidence in VFR through the TAF period. Westerly winds will prevail.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with southwesterly flow at MRY and VFR with northwesterly flow at SNS. Low confidence on the return of IFR conditions to the terminals tonight; if they do return, it will likely be brief and/or intermittent in the 12Z-16Z time frame. Onshore winds will prevail.

MARINE
(Tonight through next Saturday)
Issued at 933 PM PDT Sun Mar 22 2026

Strong northerly winds will slowly begin to diminish tonight with moderate to fresh northwesterly breezes prevailing Monday and Tuesday. Widespread hazardous marine conditions return Wednesday with strong to near gale northerly breezes and rough to very rough seas.

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...Small Craft Advisory until 9 AM PDT Monday for Pigeon Pt to Pt Pinos 10-60 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-Pt Reyes to Pigeon Pt 0-10 nm.