Marine Weather and Tide Forecast for East Richmond Heights, CA

UPDATE
Issued at 845 PM PDT Thu May 15 2025

No changes in the forecast this evening. A series of upper level shortwave energy will continue to transect NoCal and the Central Coast tomorrow into the weekend. Gusty winds at higher elevations tomorrow will become more wide spread into the lower elevations and coastal areas on Saturday. Marine layer stratus will be spotty tonight, with an increase in coverage expected by late Friday night into Saturday as more robust onshore flow along the coast develops for the weekend.

SHORT TERM
(This evening through Friday)
Issued at 1241 PM PDT Thu May 15 2025

Satellite imagery shows lingering stratus at the immediate coast of the San Mateo Peninsula and the Big Sur Coast. With an upper level ridge across the West Coast, overall conditions remain dry and seasonably warm throughout the region with highs ranging from the middle 70s to the lower 80s inland and the middle 60s to lower 70s along the Bayshore, while onshore flow keeps the coastal regions cool with highs in the upper 50s to lower 60s. Friday's forecast is quite similar in the inland areas, but a stronger onshore flow should result in slightly cooler conditions in the coastal valleys, such as the southern reaches of the SF Bay (Redwood City and Fremont southwards), the Santa Clara valley, and the northern Salinas Valley, where around 3 to 5 degrees of cooling are expected. Meanwhile, morning lows hover around the upper 40s to the middle 50s for most people, with pockets of lower to middle 40s in the highest peaks.

LONG TERM
(Friday night through next Wednesday)
Issued at 1241 PM PDT Thu May 15 2025

Later on Friday through Saturday, an upper level trough will develop off the Pacific Northwest and deepen as it travels into the Great Basin, causing a dip in temperatures for the upcoming weekend. The ensemble models are starting to converge on a more open trough to continue into the Intermountain West or perhaps the Great Plains, as opposed to the Great Basin cutoff low that we had anticipated at this time yesterday, but this is a distinction without a difference for Saturday's high temperatures, which will dip by around 10 degrees in the interior valleys, to around the middle 60s to lower 70s, while the Bayshore drops into the lower to middle 60s. Although the trough will continue to move eastwards, leaving a classic "inside slider" scenario less likely, the pressure gradient between the cutoff low and a ridge in the eastern Pacific will still result in gusty winds across the region later on Friday into Sunday. The current forecast continues to show wind gusts reaching 25 to 35 mph across the region with gusts up to 45 mph possible at the ridgelines, along the coast, and through favored gaps and passes.

Warming temperatures will return for the early part of next week with high temperatures rising to the middle 80s to lower 90s inland, or around 5 to 10 degrees above seasonal averages. Low temperatures should remain relatively stable near the upper 40s to middle 50s for the lower elevations, which should help alleviate concerns for heat- related illnesses for all but the most sensitive populations. Late Sunday and Monday, northerly winds could develop on the backside of the trough in the interior regions, especially in Napa County and the interior East Bay, helping to reinforce the warmer and drier conditions in those areas. Towards, and beyond, the end of the 7 day forecast, ensemble model clusters begin to diverge on the upper level pattern, with around 20% of ensembles developing an upper level trough heading into the start of the Memorial Day weekend, another 20-30% anticipating more zonal flow, and the remaining 50- 60% holding onto the ridge.

AVIATION
(00Z TAFS)
Issued at 451 PM PDT Thu May 15 2025

Patchy stratus is expected overnight with highest confidence in stratus at MRY and SNS. Confidence is low to moderate that stratus will reach HAF with high resolution HRRR guidance showing stratus persisting south of HAF along the San Mateo Peninsula. Otherwise, high level clouds will move in overnight with all other sites to remain VFR through the period. Fog is not expected to develop at STS and APC overnight with high clouds and drier conditions keeping the chance for fog development low. Breezy onshore winds develop tomorrow with most sites gusting between 15 to 25 knots tomorrow afternoon/evening. Some potential for low level wind shear around 1000-1500 ft at STS and APC overnight into tomorrow morning but confidence is low.

Vicinity of SFO...Diurnally breezy winds continue today and tomorrow with gusts up to 29 knots possible but are expected to weaken overnight. SFO is expected to stay VFR through the TAF period with a low chance of MVFR CIGs between 12Z-18Z. Conditions look to dry to support BKN/OVC CIGs but FEW/SCT low clouds may develop early tomorrow morning.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR becoming MVFR overnight. CIGs are expected to build in later this evening around 10Z with patchy CIGs possible from 06Z-10Z. CIGs look to clear around 19Z for SNS and between 20-21Z at MRY. Confidence is low to moderate on clearing time for MRY with a few models suggesting clearing could occur closer to 22Z. Winds remain onshore through the forecast period with diurnally breezy winds during the day today and tomorrow. Winds will be slightly breezier tomorrow with gusts to around 15-20 knots possible.

MARINE
(Tonight through next Wednesday)
Issued at 845 PM PDT Thu May 15 2025

Fresh to strong northwest winds continue over the coastal waters with gale force gusts over the outer waters. Near gale force to gale force gusts will become more widespread Friday morning into Saturday. Winds will further increase late Saturday night into Sunday with widespread gale force gusts to continue through the early work week. Moderate seas and steep, wind-driven fresh swell will continue through the early work week with significant wave heights between 10 to 12 feet. Conditions over the outer waters will worsen Sunday into the early work week as winds increase.
Hazardous conditions will continue through the end of the forecast period.

MTR WATCHES/WARNINGS/ADVISORIES
CA...None.
PZ...Small Craft Advisory from 3 PM Friday to 3 AM PDT Saturday for Mry Bay-SF Bay N of Bay Bridge.

Small Craft Advisory until 9 PM PDT this evening for Mry Bay.

Gale Warning until 3 AM PDT Saturday 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 Reyes to Pigeon Pt 0-10 nm.

Small Craft Advisory until 3 PM PDT Friday for Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.

Gale Warning from 3 PM Friday to 3 AM PDT Saturday for Pigeon Pt to Pt Pinos 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm.