Marine Weather and Tides
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
|Sunrise 5:56AM||Sunset 8:34PM||Saturday July 11, 2020 2:12 PM PDT (21:12 UTC)||Moonrise 11:59PM||Moonset 11:33AM||Illumination 61%|
7 Day Forecast for Marine Location Near Point Arena, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS66 KMTR 111743 AFDMTR
Area Forecast Discussion National Weather Service San Francisco Bay Area 1043 AM PDT Sat Jul 11 2020
SYNOPSIS. High pressure will dominate the weather pattern over the region this weekend resulting in very warm temperatures across the interior. Continued onshore flow will keep conditions near the coast cooler, yet still mild. A subtle cooling trend is on track to occur early next week.
DISCUSSION. as of 09:16 AM PDT Saturday . Low clouds and fog have begun to dissipate this morning along the coast, with patchy areas primarily over Santa Cruz county, Marin County, and the San Francisco Peninsula. Pressure gradient between SFO and ACV remained steady at around 5mb, indicative of our compressed marine layer. Fort Ord Profiler captured the shallow layer overnight, with some recovery this morning before going back to its gradual dissipation. As of this morning the most notable patch of the marine layer is a small, but growing marine layer deck due west of the San Francisco Peninsula. Expect that area to be the deepest spot for the marine layer along the CWA coastline today. In terms of temperatures and humidity overnight, RH values over higher terrain locations primarily along the East and North Bay were fairly low, with similar conditions expected Saturday night owing to the upper-level ridge setup.
The 590dm 500mb ridge over the Southwestern US has continued its expansion and will be the primary driver for our weather this weekend. Mild conditions are expected along the coast owing to greater diurnal heating as the marine layer influence remains low, while interior locations from Hollister up to Napa Valley will reach well over 90 degrees today. Some isolated areas can also expect to hit and surpass the 100 degree mark this afternoon.
Weak onshore flow is expected tonight, which will likely result in poor humidity recoveries in areas and overnight lows ranging between 60s and low 70s along our interior, especially in our higher elevations.
Sunday will be our warmest day, with mild coastal temperatures along with hot interior temperatures expected. Temps along the coast will land within the 65-75 F range while some of our interior locations should expect to reach the mid-90s. Moreover,some areas across the interior could easily experience highs in the 100-105 F range. Thankfully, models are suggesting there will be weak offshore flow owing to the stable conditions from the upper-level ridge. Nevertheless, the poor humidity recoveries along with the warmth this weekend will still result in elevated fire weather and heat concerns, especially for Sunday.
Looking ahead into next week, heights will fall across the CWA as the upper-level ridge weakens and allows for the intrusion of a disturbance off the Pacific into BC. Temperatures will return closer to seasonal averages by the first half of next week as a result. This disturbance will also allow for the marine layer to recover, bringing coastal locations back to their seasonal averages as well. Expect the main setup for next week to be the gradual shift in our upper-level setup as the ridge weakens and makes its way out of the southwest as this trough takes over.
AVIATION. as of 10:45 AM PDT Saturday . Widespread VFR with only a few hints of the marine layer left along the Marin headlands and offshore of the San Francisco Peninsula. Generally light onshore winds are prevailing this morning but will give way to moderate onshore winds, particularly through coastal gaps such as near KSFO, through the remainder of the day. For tonight, a compressed marine layer may bring a few clouds along the coast and bayshore, but otherwise VFR is expected. Tomorrow will see similar moderate onshore winds and VFR conditions as well.
Vicinity of KSFO . VFR, west to northwest wind increasing to 20 to 25 knots by early afternoon. Gusts should be infrequent but may approach 30kt if they develop. Wind easing tonight and Sunday morning but pick up again Sunday afternoon.
SFO Bridge Approach . Similar to KSFO.
Monterey Bay Terminals . VFR today. Calm winds shifting to west to northwest 10 to 15 knots by early afternoon. Generally VFR tonight though a few patches of low BKN/OVC clouds may develop late into the night for a few hours near KMRY/KWVI.
MARINE. as of 10:38 AM PDT Saturday . Moderate locally gusty northwest winds through the weekend. These winds will generate steep fresh wind driven northwest swell which will result in hazardous conditions for small craft vessels in the coastal waters. Otherwise, a light longer period south swell will be mixed in with the steep fresh northwest swell.
MTR WATCHES/WARNINGS/ADVISORIES. Tday. SCA . Pt Reyes to Pigeon Pt 0-10 nm until 3 PM SCA . Pigeon Pt to Pt Pinos 0-10 nm until 3 PM SCA . Pt Arena to Pigeon Pt 10-60 nm SCA . Pt Arena to Pt Reyes 0-10 nm SCA . Pt Pinos to Pt Piedras Blancas 0-10 nm SCA . Pigeon Pt to Pt Piedras Blancas 10-60 nm
PUBLIC FORECAST: Diaz/MM AVIATION: DRP MARINE: DRP
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NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for San Francisco/Monterey Bay Area, CA (17,4,5,8)(on/off)  Help
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