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Marine Weather and Tides Belvedere, CA Version 3.4

NOTICE 6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen

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Sunrise 5:45AM

Sunset 8:35PM

Monday June 17, 2019 4:40 AM PDT (11:40 UTC)

Moonrise 8:07PM

Moonset 5:08AM

Illumination 100%

NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.

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7 Day Forecast for Marine Location Near Belvedere, CA

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Area Discussion for - San Francisco/Monterey Bay Area, CA

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Fxus66 kmtr 171003 afdmtr area forecast discussion national weather service san francisco bay area 303 am pdt Mon jun 17 2019 Synopsis Warmer temperatures are forecast for today and Tuesday as high pressure strengthens over california, and onshore flow weakens. However, warming at coastal areas will be limited due to persistent onshore winds. Seasonable temperatures, along with areas of night and morning low clouds, are forecast through the end of the week and into next weekend. Discussion As of 3:00 am pdt Monday... Low clouds have developed well inland, and into most valleys, once again this morning as the marine layer remains relatively deep (2000 feet currently at fort ord). Patchy drizzle is occurring in coastal areas, but drizzle is not as widespread, or generating as much measurable precipitation, compared to early yesterday morning. The marine layer is expected to compress today as an upper ridge over the eastern pacific starts to build inland across northern california. Also, surface onshore pressure gradients are trending weaker. These developments are expected to result in earlier inland clearing of low clouds today as well as warmer temperatures. Today's high temperatures are forecast to be 5 to 10 degrees warmer than yesterday in most areas, which would bring our temps back to about seasonal averages. Persistent onshore flow and only partial afternoon clearing near the ocean will mean warming near the coast today will only be about 5 degrees, or less. The most robust warming will occur in the hills and inland valleys. The national blend of models (nbm) has been too warm over the past few days, and this warm bias by the nbm appears to be continuing. Therefore, maximum temperatures for today, and through much of the week ahead, have been adjusted downward from the nbm by an average of about five degrees. Another area where the nbm appears to be deficient is in how it's handling marine layer clouds. Specifically, low clouds are more widespread at present than indicated by the nbm, and the nbm is indicating a significant reduction in night and morning low clouds as the week progresses, something that doesn't appear to be rooted in reality given the persistent onshore flow depicted by the models. Therefore, cloud cover has been increased, particularly in coastal areas, over what is forecast by the nbm. Warmer temperatures are expected to persist into Tuesday. In fact, we will likely see a few additional degrees of warming on Tuesday as h5 heights increase to 588 dm and 850 mb temps warm to

25 deg c. However, temperatures at the surface are not expected to warm anywhere near the record-breaking heat of a weak ago when offshore flow developed. By contrast, onshore flow is expected to persist this week which will keep surface temperatures in check, particularly in coastal areas. An upper trough currently in the gulf of alaska is forecast to slide to the southeast and into the pacific northwest by midweek. This will likely result in slight cooling on Wednesday, and a few additional degrees of cooling on Thursday as the trough digs into the northern great basin, forcing the ridge to retreat offshore. Temperatures are then forecast to warm slightly at the end of the week and into the early part of the weekend. But beyond that, both the GFS and ECMWF ensemble means indicate that an upper trough will be centered along the west coast, which will likely mean cooler than normal temperatures late in the weekend and into the first part of next week. Aviation As of 10:45 pm pdt Sunday... The strong north-south component of the onshore gradient has kept stratus out of sfo so far this evening but satellite image shows it is expanding inside the bay. Therefore look for low clouds to spread over sfo bay overnight. Ft ord profiler shows the marine layer is trending lower so the cloud bases will be in the ifr range. The clouds should also burn off earlier on Monday. As an upper level ridge builds into the pacific northwest Monday night the flow above the inversion will become more offshore. This will bring drier air down to the surface resulting in less clouds for Monday night. Vicinity of ksfo... Ifr CIGS after 06z with bases 800-1000 feet. Sfo bridge approach... Similar to ksfo. Monterey bay terminals... Ifr CIGS clearing after 18z at sns and 19z at mry. Marine As of 10:40 pm pdt Sunday... High pressure off the pacific northwest will keep the strongest winds over the northern outer waters through next week. Mtr watches warnings advisories Tday Sca... Pt arena to pt reyes 0-10 nm sca... Pt arena to pigeon pt 10-60 nm sca... Pigeon pt to pt piedras blancas 10-60 nm until 3 pm public forecast: dykema aviation: W pi marine: W pi visit us at

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
TIBC1 - Tiburon Pier, San Francisco Bay, CA	4 mi	54 min	S 8.9	54°F			1010 hPa
46237 - San Francisco Bar, CA (142)	11 mi	71 min			56°F	5 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA	22 mi	31 min	NNW 9.7 G 14	54°F	56°F		1010.1 hPa
SFXC1 - San Francisco Bay Reserve, CA	34 mi	116 min	WNW 6	56°F			1009 hPa	52°F

Wind History for San Francisco, CA

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Oakland, Metro Oakland International Airport, CA	15 mi	48 min	SW 4	10.00 mi	Overcast	59°F	52°F	78%	1009.9 hPa
San Francisco, San Francisco International Airport, CA	15 mi	45 min	S 5	10.00 mi	A Few Clouds	56°F	48°F	77%	1009.8 hPa
Hayward, Hayward Air Terminal, CA	21 mi	47 min	N 0	10.00 mi	Overcast	58°F	53°F	84%	1010.7 hPa
Half Moon Bay Airport, CA	22 mi	46 min	SSE 8	4.00 mi	Fog/Mist	54°F	50°F	88%	1010.8 hPa
Concord, Buchanan Field, CA	23 mi	48 min	no data	10.00 mi	Fair	58°F	50°F	75%	1007.4 hPa
Novato / Gnoss Field, CA	23 mi	46 min	N 0	10.00 mi	Fair	52°F	51°F	100%	1009.8 hPa

Wind History from SFO (wind in knots)

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Tide / Current Tables for Alcatraz Island, San Francisco Bay, California

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Tide / Current Tables for Alcatraz Island W, San Francisco Bay, California Current

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Weather Map and Satellite Images

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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

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Wind Forecast for San Francisco/Monterey Bay Area, CA (7,2,3,4)

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Ground Weather Radar Station San Francisco Bay Area, CA

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Disclaimer: 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.