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 5:53AM||Sunset 8:31PM||Sunday July 5, 2020 6:48 PM PDT (01:48 UTC)||Moonrise 8:26PM||Moonset 5:26AM||Illumination 100%|
7 Day Forecast for Marine Location Near Carmel-by-the-Sea, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS66 KMTR 060044 AFDMTR
Area Forecast Discussion National Weather Service San Francisco Bay Area 544 PM PDT Sun Jul 5 2020
SYNOPSIS. Temperatures are warm and conditions are dry with breezy onshore winds. Monday afternoon high temperatures will be slightly cooler as onshore flow increases with a likely return of the marine layer for the immediate coastline. Temperatures are expected to be similar day- to- day midweek before warming likely late in the week and into next weekend.
DISCUSSION. as of 01:42 PM PDT Sunday . Temperatures Sunday are running similar to yesterday given the high pressure still located over the Bay Area region. A few observations in the North Bay are slightly warmer, but generally speaking the pattern and conditions are consistent to yesterday. Winds remain on onshore and have started to increase this afternoon. Despite the onshore direction, coupled with the dry conditions over inland areas, the winds could make fire containment challenging. However, as an update to the previous discussion, it appears that the Park Fire is now improved to 50% contained and crews and stopped its forward progress. Sky conditions remain clear as the nearest bit of cloud cover is over 100 miles off the California coast.
The pattern changes slightly beginning overnight tonight, being driven by an upper level trough currently northwest of the state of Washington. As it moves down the Pacific coast tonight, expect a deeper marine layer and a return of low clouds around the Monterey Peninsula. Winds will remain onshore but increase overnight as well, reaching farther inland. These cooler northwesterly winds will drive 5-7 degrees cooler temperatures on Monday, with isolated locations seeing a 10 degree cool down.
As the trough moves through, these cooler temperatures in the 70s and 80s will remain through the midweek. Winds will remain onshore and be breezy. In a return to the weather pattern from last week, high pressure to the southeast will once again build by the end of the week. The return of higher pressure puts a warming trend in the forecast for the weekend. Drier conditions prevail with no precipitation forecast.
AVIATION. as of 5:44 PM PDT Sunday . for 00Z TAFS. It's VFR, a few patches of coastal stratus and fog may redevelop tonight and Monday morning. At this time similar to yesterday a dry mid-latitude flow continues to prevent fog and stratus development. 24 hr trends in temperatures and dew point temperatures support high confidence VFR forecast for the evening and VFR continuing for the Bay Area tonight and Monday morning due to sufficient northerly pressure gradient and winds. Lower level cooling and weakening of the flat 500 mb height ridge is forecast tonight, Monday and Monday night which will likely weaken the marine layer temperature inversion at least a little bit and increase the marine layer depth.
The marine layer depth varies from 1,200 to 1,600 feet. A surface high pressure ridge over northern California is producing a 7.4 mb ACV-SFO pressure gradient and 2.2 mb UKI-STS gradient. The 18z NAM is under-forecasting the ACV-SFO pressure gradient by almost 2 mb which is quite likely resulting in stronger northwest winds over the coast than modeled. Also, visible imagery shows clear conditions over the coastal waters thus turbulent mixing and diffusion of much drier air at or above the marine temperature inversion continues to enter the boundary layer preventing marine fog and stratus from developing. On the flip side both UKI-STS and SFO-SMX gradients are over-forecast by the 18z NAM, although as mentioned the UKI-STS gradient is 2.2 mb, the gradient now strengthening closer to 18z NAM forecasts; the northerly gradient and winds is causing downsloping warming and drying over the North Bay, e.g. STS has sustained NW wind near 15 knots.
Not much let up in the strength of the aforementioned pressure gradients is forecast tonight and Monday morning.
Vicinity of KSFO . VFR. 5 minute obs showing a stronger west wind with gusts up over 30 knots likely into the evening close to airport weather warning criteria for winds, criteria is 35 knots or higher sustained or gusts. Looks good for VFR through the taf period given overall conditions mainly due to a strengthening northerly ACV-SFO pressure gradient, currently 7.4 mb. Similarly, a gusty west wind is forecast Monday and Tuesday afternoons and evenings per statistical guidance.
SFO Bridge Approach . Similar to KSFO.
Monterey Bay Terminals . VFR. Not a clear cut VFR forecast for tonight with strengthening northerly gradients, though at least at the onset for the evening with plenty of mixing of drier air into the boundary layer should keep VFR going. Later tonight and Monday morning there's the possibility of patchy IFR in fog and stratus briefly forming until diurnal mixing mixes out any fog and/or stratus by late Monday morning.
MARINE. as of 01:42 PM PDT Sunday . A 1030 mb high centered 1000 miles west of Cape Mendocino will move closer to the coast through Monday. As a result, gusty northwest winds will continue over the coastal waters into midweek. Gale force gusts are possible along the Big Sur coast Monday afternoon and evening. Strong northwest winds will generate steep fresh swell resulting in hazardous seas conditions. A long- period southerly swell will continue through Monday before swell periods begin to subside.
MTR WATCHES/WARNINGS/ADVISORIES. Tngt. SCA . Pt Arena to Pt Reyes 0-10 nm SCA . Pt Reyes to Pigeon Pt 0-10 nm SCA . Pigeon Pt to Pt Pinos 0-10 nm SCA . Pt Arena to Pigeon Pt 10-60 nm SCA . Pigeon Pt to Pt Piedras Blancas 10-60 nm SCA . Pt Pinos to Pt Piedras Blancas 0-10 nm SCA . Mry Bay until 9 PM
PUBLIC FORECAST: DK AVIATION: Canepa MARINE: RGass
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Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|46028 - CAPE SAN MARTIN - 55NM West Northwest of Morro Bay, CA||97 mi||38 min||NW 27 G 33||58°F||56°F||1013.1 hPa||55°F|
|46239 - Point Sur, CA (157)||100 mi||52 min||56°F||9 ft|
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Monterey Regional Airport, CA||120 mi||54 min||W 9 G 16||10.00 mi||Fair||69°F||46°F||45%||1016.9 hPa|
Link to 5 minute data for KMRY
Wind History from MRY (wind in knots)
|1 day ago||NW||NW||W||W||W||E||E||Calm||Calm||Calm||Calm||SE||Calm||Calm||NW||N||N||N||N||N||NW||N||NW|
|2 days ago||SW|
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GEOS Local Image of CentralWestCoast EDIT
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.
Link to Loop
Other links: Northern Pacific Contential US Full GOES-East
Wind Forecast for San Francisco/Monterey Bay Area, CA (21,6,7,8)(on/off)  Help
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