Marine Weather and Tide Forecast for Bonny Doon, CA

SHORT TERM
(This evening through Monday)
Issued at 1243 PM PST Sun Jan 12 2025

Today will bring plentiful sunshine and dry conditions with temperatures as much as 10 degrees above normal. Clear conditions overnight will maximize radiational cooling, thus a Frost Advisory has been issued from 1 AM Monday through 9 AM Monday for the East Bay Hills, East Bay Valleys, Santa Clara Valley, Eastern Santa Clara Hills, and Interior Central Coast. The coldest conditions are expected outside of major cities due to the urban heat island effect, i.e. temperatures of 33 to 36 degrees are not expected in San Jose but are expected in southern portions of the Santa Clara Valley along the US-101 corridor. Please make sure that pets and plants have appropriate shelter.

The overall upper air pattern is in an Omega Block; however, by this evening a shortwave trough will dig from north to south and become a cutoff low over the Eastern Pacific Ocean forming a Rex Block. At the surface there is a coastal trough off the West Coast and high pressure across the West. This is a textbook offshore flow setup.
Evidence of that is a -5.7 mb SFO-WMC surface pressure gradient which is forecast to strengthen through Monday morning as the shortwave trough traverses the region. The surface pressure gradient is expected to be tightest over the North Bay, thus a Wind Advisory has been issued from 2 AM Monday through 10 AM Tuesday for the North Bay Interior Mountains for northerly to northeasterly winds of 25 to 35 mph with gusts up to 55 mph. The downsloping (warming) nature of the winds will keep the North Bay just warm enough to remain excluded from the Frost Advisory for tonight.

A Coastal Flood Advisory is in effect from 7 AM to 1 PM Monday for bayshore locations along the San Francisco Bay and San Pablo Bay.
Expect minor coastal flooding from King Tides, particularly in low- lying roadways of Marin County.

LONG TERM
(Monday night through next Saturday)
Issued at 1243 PM PST Sun Jan 12 2025

Tuesday through Saturday is more of the same: dry and mild. The Rex Block is expected to break down Thursday which will allow for the return of at least some onshore flow in the form of the afternoon sea breeze. The dry air mass and lack of clouds will continue to allow for maximal radiational cooling overnight with Frost Advisories likely needed every night this week in at least one zone. Want an inside scoop? CPC has the region leaning below normal for temperatures and precipitation through January 26th.
Now would be a great time to get outdoor projects done like making sure your gutters are cleaned out and loose tree limbs are removed, or you can simply enjoy the beach in January.

AVIATION
(00Z TAFS)
Issued at 312 PM PST Sun Jan 12 2025

Clear skies throughout the region. VFR will prevail through the TAF period. N/NE winds will will remain moderate to breezy into the evening hours before becoming light temporarily. Early Monday morning expect breezy and gusty conditions to return for most terminals and will linger into the early afternoon hours before returning to moderate speeds. LLWS is possible for terminals in the North Bay as a low-level jet passes over the terminal, especially over KSTS.

Vicinity of SFO...VFR through the TAF period with light to variable winds into the night. Near 12Z N/NE winds rebuild to up to 15-16 knots and expected to linger into the early afternoon before moderate speeds return. Timing is a bit uncertain as some models suggest winds ease near 22-23Z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the TAF period. Light winds continue into the night. SE moderate to breezy drainage winds build near the terminals overnight, especially over KSNS.

MARINE
(Tonight through next Friday)
Issued at 312 PM PST Sun Jan 12 2025

Strong winds continue across portions of the northern outer waters with gale force gusts. Breezy to gusty winds continue for the waters through late tonight and early Monday morning, but look to ease into the work week. Hazardous conditions for small crafts will persist through Monday with elevated wave heights between 10 to 15 feet expected. Significant wave heights will remain elevated through the early work week but will subside below small craft criteria by mid week.

MTR WATCHES/WARNINGS/ADVISORIES
CA...Coastal Flood Advisory from 7 AM to 1 PM PST Monday for CAZ006- 506-508.

Wind Advisory from 2 AM Monday to 10 AM PST Tuesday for CAZ504.

Frost Advisory from 1 AM to 9 AM PST Monday for CAZ510-513>518- 528.

PZ...Small Craft Advisory from 3 AM to 3 PM PST Monday for Pt Reyes to Pigeon Pt 0-10 nm-SF Bay N of Bay Bridge.

Small Craft Advisory until 3 PM PST Monday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 0-10 nm.

Gale Warning until 9 AM PST Monday for Pt Arena to Pt Reyes 10- 60 NM.