Marine Weather and Tides
3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
|Sunrise 6:19AM||Sunset 7:53PM||Monday April 23, 2018 8:01 PM PDT (03:01 UTC)||Moonrise 12:22PM||Moonset 1:48AM||Illumination 63%|
EDIT (on/off)  Help
|PZZ530 San Pablo Bay Suisun Bay The West Delta And San Francisco Bay North Of The Bay Bridge- 721 Pm Pdt Mon Apr 23 2018 |
.small craft advisory in effect until 10 pm pdt this evening...
Tonight..SW winds 15 to 30 kt...winds decreasing to 10 to 20 kt late.
Tue..SW winds 10 to 20 kt...with afternoon gusts to 25 kt possible.
Tue night..SW winds 10 to 20 kt...evening gusts to 25 kt.
Wed..SW winds 5 to 15 kt.
Wed night..SW winds 10 to 20 kt.
Thu..SW winds 10 to 20 kt...decreasing to 10 kt.
Fri..SW winds 5 to 15 kt.
Sat..W winds 5 to 15 kt. Slight chance of showers.
|PZZ500 721 Pm Pdt Mon Apr 23 2018 |
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Northwest winds will remain light to moderate through most of the week as an area of low pressure approaches the coast. Onshore winds will remain strong and gusty north of the bay bridge this evening, possibly gusty into the overnight hours. Light to moderate seas will prevail through the forecast period with a mixed southerly and northwesterly swell developing late this week.
7 Day Forecast for Marine Location Near Shell Ridge, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus66 kmtr 240043|
area forecast discussion
national weather service san francisco bay area
543 pm pdt Mon apr 23 2018
Synopsis Dry and seasonably warm conditions will continue
today. A cooling trend is forecast from Tuesday through the end of
the week as an area of low pressure offshore slowly approaches the
coast. This low pressure may produce scattered showers from late
Friday into Saturday, mainly across the north.
Discussion As of 01:27 pm pdt Monday... Sunny skies prevail
across most of the bay area this afternoon. The sunshine and light
winds have allowed for well above normal temperatures away from
the coast. Afternoon temps will likely top out in the 70s to mid
80s. Just like during the summer months, different story at the
coast. Weak pressure gradients n-s and e-w have kept low clouds
along the coast, mainly san mateo coast southward. Made some late
day adjust to the forecast to lower temps around the monterey bay
and keep clouds through the afternoon.
Otherwise, only minor tweaks were made to the forecast. High
pressure will continue to weaken as an upper low currently
spinning off the west coast slowly tracks eastward. Night and
morning low clouds will continue through Wednesday and possibly
mix out completely by Thursday Friday. The lower 500mb heights and
cooler 850mb temps will translate to a slight downward trend in
daytime high temperatures. Temps by Wednesday will be closer to
normal (60s coast, 70s to lower 80s inland) and possibly below
normal by Thursday (60s 70s).
The track of upper lows are always difficult to forecast,
especially in the medium to long range. The 12z model run didn't
shed any new light on the rain potential Friday into Saturday.
Model consensus brings an upper low into far norcal with some
precip possible across the north bay. Confidence is low and will
maintain the slight chc of showers sf bay northward. QPF looks to
be minimal at this point.
Aviation As of 5:43 pm pdt Monday... It's a summer-like
afternoon, cooler ocean to warmer hot land temperature (and
pressure) contrasts have steepened, coastal stratus and fog are
hugging the coastline. The onshore pressure gradient sfo-sac is
1.4 mb while southerly pressure gradients smx-sfo and sns-sjc are
a bit stronger at 2.0 mb and 3.3 mb (strong) respectively, under-
forecast by recent NAM output and sufficient for the development
of a coastally trapped southerly wind reversal if these readings
held, however coastal buoys are mostly showing wsw-w wind
direction and stratus and fog motion following suite presently.
The southerly gradients may relax by mid-late evening, however|
it'll be relatively short-lived as southerly gradients should
strengthen again Tuesday into Tuesday night. The marine layer
slopes from approx 1000 feet in the bay area to 1400 feet north
central coast per profiler data.
With exception of ksfo, koak, ksjc, klvk 00z tafs are geared a
little more toward ifr CIGS and visibilities developing this
evening. Conditions are ideal for ifr lifr vlifr tonight into
Tuesday morning along the immediate coast with some inland
intrusion through the golden gate. With exception of a
strengthening offshore pressure gradient wmc-sfo reaching near 10
mb (nam model showing ~ 4 mb onshore bias) by early Tuesday
morning the large scale pattern is otherwise nearly persistence
for tonight into Tuesday. The developing offshore gradient may
tend to hold areal coverage of stratus and fog at a minimum into
the bay area tonight, the offshore gradient will be weaker Tuesday
night into Wednesday thus allowing a better set up for stratus and
fog intrusion at that time.
Vicinity of ksfo...VFR, w-nw wind with occasional gusts to 20-25
knots til 04z. Near high confidenceVFR holds this evening based
on present depth of the marine layer (near 1000 feet) and little
lower level temperature change tonight. Radiative cooling improves
tonight with a clear sky, near surface cooling is a little more
pronounced Tuesday morning which may result in a patch or two of
fog or low stratus, but for now going with aVFR forecast looks
Sfo bridge approach... Similar to ksfo.
Monterey bay terminals... Visible imagery shows stratus and fog
nearby, w-nw wind flow should bring in ifr early this evening.
Tempo ifr 00z-03z, prevailing ifr lifr for the overnight hours.
Late morning mixing should help result in a return ofVFR for the
area terminals. Stratus and fog likely to roll back inland early
Marine As of 4:57 pm pdt Monday... Northwest winds will remain
light to moderate through most of the week as an area of low
pressure approaches the coast. Light to moderate seas will prevail
through the forecast period with a mixed southerly and northwesterly
swell developing late this week.
Mtr watches warnings advisories
Public forecast: mm
visit us at
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Wind History for Union Pacific Rail Road Bridge (UPRR), CA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Concord, Buchanan Field, CA||6 mi||69 min||WNW 9||10.00 mi||Fair||80°F||53°F||39%||1011.2 hPa|
|Oakland, Metro Oakland International Airport, CA||17 mi||69 min||WNW 13||9.00 mi||Partly Cloudy||59°F||52°F||78%||1014.3 hPa|
|Hayward, Hayward Air Terminal, CA||17 mi||68 min||NW 11||10.00 mi||Fair||65°F||50°F||59%||1014.8 hPa|
|Livermore, Livermore Municipal Airport, CA||18 mi||69 min||W 9||10.00 mi||Fair||74°F||54°F||50%||1012.6 hPa|
Wind History from CCR (wind in knots)
|1 day ago||N||Calm||S||Calm||NW||Calm||N||Calm||Calm||NW||E||SW||Calm||Calm||Calm||N||N||NW||NW|
|2 days ago||SW||S||S||S||S||S||S||S||S||W||Calm||S||Calm||Calm||NE||NW||N||W||W||NW |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
|Suisun Point |
Click for Map
Mon -- 02:34 AM PDT 1.88 feet Low Tide
Mon -- 02:48 AM PDT Moonset
Mon -- 06:22 AM PDT Sunrise
Mon -- 08:05 AM PDT 4.50 feet High Tide
Mon -- 01:22 PM PDT Moonrise
Mon -- 03:49 PM PDT -0.25 feet Low Tide
Mon -- 07:52 PM PDT Sunset
Mon -- 10:26 PM PDT 4.41 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|Stake Point .9 Mi NNW |
Click for Map
Mon -- 12:08 AM PDT -0.00 knots Slack
Mon -- 02:35 AM PDT -0.42 knots Max Ebb
Mon -- 02:47 AM PDT Moonset
Mon -- 04:43 AM PDT 0.00 knots Slack
Mon -- 06:21 AM PDT Sunrise
Mon -- 07:57 AM PDT 0.68 knots Max Flood
Mon -- 10:44 AM PDT -0.00 knots Slack
Mon -- 01:21 PM PDT Moonrise
Mon -- 02:20 PM PDT -0.79 knots Max Ebb
Mon -- 05:56 PM PDT 0.00 knots Slack
Mon -- 07:51 PM PDT Sunset
Mon -- 10:14 PM PDT 0.86 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  HelpWeather Map
GOES 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 (23,6,7,8)(on/off)  Help
Ad by Google
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.