San Francisco Bay north of the Bay Bridge, including San Pablo Bay, Suisun Bay, and West Delta, CA Marine Forecast
| Today...Nw Winds Around 5 Knots, Becoming Sw 10 To 15 Knots This Afternoon. |
| Tonight...W Winds 10 To 15 Knots. |
| Fri...Sw Winds 5 To 10 Knots. |
| Fri Night...W Winds 10 To 15 Knots. |
| Sat...S Winds 5 To 10 Knots. |
| Sat Night...Sw Winds 10 To 15 Knots. |
| Sun...W Winds 10 To 15 Knots. |
| Mon...Nw Winds 10 To 20 Knots With Gusts Up To 30 Knots. |
| Area Forecast Discussion National Weather Service San Francisco Bay Area 430am PDT Thu Mar 30 2023 Synopsis Showers ending this morning with below average temperatures into the weekend. Light rain chances return for this weekend into early next week, but amounts should be on the light side. As of 01:00am PDT Thursday... Today And Tonight A closed upper low -- initially across the Bay Area this morning -- will progress into SoCal and the Desert Southwest while devolving to an open-wave trough. Geopotential heigheights will rise in its wake as surface high pressure noses in from the subtropical Pacific. Cool northerly post-frontal flow will ensue with low-level winds turning onshore this afternoon. Any showers should be waning this morning but with residual 1000-850 mb moisture expect some lower clouds to hang around through the day. High temperatures should be around 6 to 8 degrees below the seasonal average and mostly in the mid to upper 50s for the lower elevations. Readings will be coolest along the immediate coast and bays given the modest onshore wind component. Lows tonight should drop into the upper 30s to around 40 with the coolest readings within the interior valleys. Frost is possible in sheltered locations within the North Bay towards morning. Friday through Sunday: Upper troughing will prevail from the Gulf of Alaska through the Pacific Northwest. The associated moisture tap will be modest and largely focused to our north on Friday. However enough moisture will accompany a weak frontal boundary drifting south over the weekend to produce low-end (~25%) light rain chances for the North Bay over the weekend. This is not looking to be an impactful event however as rain totals should remain on the light side. Temperatures will remain below seasonal norms with highs in the 50s to lower 60s and lows in the upper 30s and 40s. Sunday night through Tuesday: Large-scale troughing will encompass much of the western CONUS while dropping from the northeast Pacific through the Four Corners region. Some precipitation may accompany this system, but the inland progression of the trough suggests somewhat meager moisture to work with. This is reflected in ensemble solutions which generally produce light (to no) rain totals across the region. However the increasing meridional flow pattern should set up a decent pressure gradient with strong high pressure over the eastern Pacific and lower pressures across the Great Basin. This suggests that gusty northerly winds may become a concern towards early next week. We'll still need time to fine tune the details however regarding exact wind magnitudes. No real changes in the temperature department with readings remaining below seasonal averages. Wednesday And Thursday There is increasing spread in deterministic model and ensemble solutions during this period leading to lower than average forecast confidence. There are some suggestions of a trough dropping south across the eastern Pacific, however the upper features are being handled quite differently among the various deterministic solutions. The deterministic GFS (Global Forecast System) spreads moisture and light rain chances onshore by late week while the ECMWF (European Centre for Medium-Range Weather Forecasts) keeps the better moisture well offshore. There's still more time for this to come into focus so for now will stick with the dry solution in our forecast as provided by the National Blend of Models through the end of the forecast period. Looking forward, it's noted in the Climate Prediction Center's Center's 6-10 and 8-14 day outlooks show lessening probabilities for above normal precipitation as we head forward into April. That would be welcome news as I think we're all ready for a break. Marine as of 04:30am PDT Thursday...Winds continue to diminish as a low moves towards the south of Point Piedras Blancas. Breezy northwest flow through the day with some higher gusts in coastal jets north of Point Reyes, south of Davenport, and south of Point Lobos. Winds diminishing through the weekend, turning southerly in the northern waters before a new storm system arrives early next week. Seas continuing to diminish through the weekend. NOAA San Francisco Bay Area Office: Watches - Warnings - Advisories Today: Frost Advisory...CAZ506 |
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