Marine Weather and Tide Forecast for Pacific Grove, CA

SHORT TERM
(Today and tonight)
Issued at 117 AM PST Mon Dec 9 2024

The forecast for cold temperatures is on track tonight, as clear skies promote radiational cooling throughout the region. As of midnight most of the region is reporting temperatures in the 40s, with the coastal and higher elevation regions seeing temperatures into the low to mid 50s. Across southern Monterey County, temperatures at midnight were 33 at the Bradley RAWS, 35 at the Parkfield RAWS, and 38 at the Fort Hunter Liggett RAWS. A Frost Advisory is now in effect for the southern Salinas Valley (beginning halfway between Soledad and Greenfield, extending to the south) and the area around San Antonio Lake, as low temperatures reach the low to mid 30s across the region. Elsewhere, the inland valleys see lows in the upper 30s to lower 40s while lows in the mid to upper 40s are expected along the coast and Bayshore.

Gusty offshore winds are also developing across the higher elevations of the Bay Area and Santa Cruz Mountains, as an "inside slider" descends through the Great Basin. The highest gusts recorded so far are a pair of 40 mph gusts at Mount Saint Helena and the Santa Fe Geothermal PG&E station. Winds will continue building through the night, with gusts topping out around 35-45 mph across eastern Napa County and 25-35 mph across higher elevations elsewhere in the Bay Area. Significantly lower gusts are expected in the valleys, and across the Central Coast. Winds will start to diminish through the day Monday but will remain gusty into the early hours of Tuesday morning.

High temperatures today range from the middle to upper 60s in the inland valleys, into the upper 50s to lower 60s along the coast, and down into the lower to middle 50s in the higher elevations.

LONG TERM
(Tuesday through Sunday)
Issued at 117 AM PST Mon Dec 9 2024

Upper level ridging will continue to promote clear skies through the next couple of days as high temperatures remain relatively similar through the midweek, with a slight cooling across the North Bay into the northern San Francisco Bay Area on Tuesday. The clear skies will help cooler temperatures take hold on Tuesday morning. A Frost ADvisory has now been issued from midnight through 9 AM on Tuesday, due to low temperatures in the low to mid 30s in the North Bay valleys, the interior East Bay, the Santa Clara Valley and east Santa Clara hills, the southern Salinas Valley, and the interior mountains of Monterey and San Benito counties. Elsewhere, low temperatures in the low to mid 40s are expected along the coastal and Bayshore regions. Wednesday sees the return of high clouds across the region with an advancing front, slightly cooling the daytime temperatures but helping warm the nights by inhibiting radiation of heat into space.

To prepare for these cold temperatures, remember the Four P's of Winter Weather:

People: Dress in layers and wear a hat that covers the ears. Pay special attention to children and the elderly, who are more vulnerable to the cold.
Plants: Bring potted plants indoors and keep outdoor plants and trees protected.
Pets: Bring all pets indoors. Pets and other animals that have to be kept outdoors should have an enclosed shelter.
Pipes: Make sure all external water pipes are insulated. Keep an interior faucet running at a drip to prevent ice buildup.

Model guidance continues to indicate that the pattern will become more active towards the middle and late part of the week. Some scattered rain chances arrive later Wednesday into Thursday, with the possible arrival of a shortwave trough. The ensemble models are beginning to converge onto the shortwave trough coming into the western US, but chances for coastal drizzle remain quite low (up to 10-30% through Wednesday and Thursday) with accumulating precipitation not expected. A stronger low pressure system arrives on Friday, bringing more impressive rain potential but with continuing uncertainty and fluctuation over the rain totals. The overall trends are still the same: greatest totals in the North Bay, with half an inch to an inch of rain in the valleys, potentially up to 2 inches in the higher elevations, with generally less than half of an inch across the rest of the Bay Area and Central Coast.
Throughout all of this, there is still room for fluctuation in the rainfall totals through Friday. Ensemble cluster analysis reveals a group of around 30-40% of the ensemble members that continue to advertise a potential for rainfall totals higher than the current forecast. Thus, continued attention to forecast updates is strongly advised.

Peeking into the early part of next week, ensemble model runs show the potential for a brief lull in the rain towards the end of the upcoming weekend, with another system possible for the early part of the week. CPC outlooks suggest that temperatures lean above seasonal averages into the third week of December, with precipitation total outlook just leaning above seasonal averages across the North Bay, and just leaning below seasonal averages in the Central Coast.

AVIATION
(06Z TAFS)
Issued at 914 PM PST Sun Dec 8 2024

Mostly VFR conditions with clear skies over the terminals but KSNS is experience MVFR visibility due to haze. Although the sounding shows that the temperature inversion is not as strong as the previous nights, there is still a chance that low visibility may develop over the terminals overnight, but confidence is low at this moment. North Bay terminals may see some fog development overnight but confidence is low. VFR is expected to return by 17-18Z, if conditions become poor overnight. Overall winds will remain light to moderate through the TAF period.

Vicinity of SFO...VFR through the TAF period with a chance for MVFR conditions overnight. Confidence is low, but if haze develops over the terminal, expect as low as 4sm near 09-10Z and lasting for a few hours. High confidence that VFR will prevail after 18Z through the remainder of the TAF period. Winds will remain light through the TAF period as well.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR/MVFR with lower visibility occuring over KSNS. There is some uncertainty on when the haze will lift and mix out, as some model suggest as late as Monday afternoon. Higher confidence that conditions should improve near 18Z, when winds start to increase.

MARINE
(Tonight through next Saturday)
Issued at 914 PM PST Sun Dec 8 2024

Northerly winds will continue to decrease tonight into Monday.
This will allow for seas to abate as well by mid- Monday. For the rest of the week, look for light, shifting wind and a moderate NW swell. As the low pressure system moves over our area by late week, expect a chance for rain, increased winds, and building seas going into the weekend.

MTR WATCHES/WARNINGS/ADVISORIES
CA...Frost Advisory from midnight tonight to 9 AM PST Tuesday for CAZ506-510-513>516-518.

Frost Advisory until 9 AM PST this morning for CAZ516.

PZ...Small Craft Advisory until 3 PM PST this afternoon for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.