Sunday, May20, 2018 L-36.com


Marine Weather and Tides
Tamalpais-Homestead Valley, CA

Version 3.4
What's New / NOTES
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 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.

Sunrise 5:53AMSunset 8:19PM Sunday May 20, 2018 2:54 PM PDT (21:54 UTC) Moonrise 10:16AMMoonset 12:00AM Illumination 35% Phase: Waxing Crescent; Moon at 6 days in cycle
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.
Marine Forecasts
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PZZ530 San Pablo Bay, Suisun Bay, The West Delta And The San Francisco Bay North Of The Bay Bridge- 241 Pm Pdt Sun May 20 2018
.small craft advisory in effect until 9 pm pdt this evening...
Tonight..W winds 10 to 20 kt with gusts up to 35 kt... Becoming sw 5 to 15 kt with gusts up to 25 kt after midnight. Patchy drizzle after midnight.
Mon..SW winds 10 to 20 kt with gusts up to 30 kt.
Mon night..SW winds 10 to 20 kt with gusts up to 30 kt.
Tue..SW winds 10 to 20 kt with gusts up to 30 kt.
Tue night..SW winds 10 to 20 kt with gusts up to 30 kt.
Wed..SW winds 10 to 20 kt with gusts up to 25 kt.
Wed night..SW winds 10 to 20 kt with gusts up to 25 kt.
Thu..SW winds up to 10 kt.
Fri..SW winds up to 10 kt.
PZZ500 241 Pm Pdt Sun May 20 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Moderate to strong northwesterly winds will persist over the coastal waters through Monday in response to a tight north to south pressure gradient along the coast. These winds will result in steep wind waves as well and produce hazardous conditions for small crafts. A long period southerly swell will increase and mix with northwesterly swell by Monday morning, gradually increasing through much of the week.

7 Day Forecast for Marine Location Near Tamalpais-Homestead Valley, CA
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location: 37.89, -122.57     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 202042
afdmtr
area forecast discussion
national weather service san francisco bay area
142 pm pdt Sun may 20 2018

Synopsis Upper low over california will keep temperatures below
normal at least through Tuesday. Weak ridge builds around midweek
with temperatures near normal before another trough approaches
Friday through Sunday with onshore winds keeping temperatures on
the cool side of normal while mainly dry conditions are forecast.

Discussion As of 1:42 pm pdt Sunday... Below normal
temperatures and breezy onshore winds continue to be the main
forecast trend. So far this afternoon temps generally running from
the upper 50s beaches, 60s around the bay and 70s well inland.

Cloud decks are around 2500 feet deep along the coast due to an
upper low over the region. The ben lomond raws up in the santa
cruz mountains is sitting in the cloud layer and so far reporting
a high of only 49 degrees so far this afternoon. Onshore gradient
of 2.5 mb from sfo to sac is pushing some gusty winds from the
golden gate out into the delta with sfo gusting to 33 mph last
hour.

Looking forward the last few NAM runs have generated some coastal
drizzle tonight with cyclonic flow aloft and moist onshore flow
lifting the boundary layer. Coastal hills from san mateo southward
to monterey that are exposed to NW winds off the ocean is where
the modeling is showing some measurable drizzle type QPF that
should it develop will be localized.

Main forecast theme to start the work week will be continued below
normal temps and breezy onshore winds. The north bay may see the
most sunshine on Monday with drier north northeast flow around
the upper low. MOS data showing 79 degrees for santa rosa on
Monday while most cities around the bay will see 60s once again
with some lower 70s for the santa clara valley.

The upper low slowly ejects inland by Tuesday but a deep marine
layer and onshore flow will likely remain in its wake with
continued trend of below normal temps and onshore breezes.

Some weak ridging or zonal type flow develops weds afternoon into
Thursday sending temps back to near normal.

Longwave trough approaches by Friday afternoon with onshore winds
and approaching upper low sending inland temps back below normal
once again for Saturday and Sunday of the upcoming memorial day
weekend. Latest ECMWF does indicate system may be progressive
with warmer high pressure by memorial day Monday but that scenario
may be dubious with developing tropical system in the gulf of
mexico potentially slowing the large scale west to east flow
across the us.

Aviation As of 10:35 am pdt Sunday... For 18z tafs. MVFR
ceilings continue to impact the san francisco bay and monterey bay
terminals this morning. Should see some partial clearing this
afternoon for the san francisco bay terminals with low clouds
likely to remain in place over the monterey bay terminals though
much of the day. Onshore winds will also increase and become gusty
at times through the afternoon and evening hours. Low clouds make
an early return once again given the deep marine layer in place
with winds diminishing slightly into Monday morning.

Moderate forecast confidence.

Vicinity of ksfo... MVFR ceilings through at least 20-21z, with
the possibility of only partial clearing this afternoon. Westerly
breezy gusty winds will continue through the day and evening. Low
MVFR ceilings, if they do scatter out, likely to make early return
late this evening.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... MVFR ceilings likely to persist over the
monterey bay terminals through the forecast period. Slight chance
of brief clearing at ksns this afternoon, but confidence is low.

Ceilings may lower to ifr tonight and into early Monday morning.

Breezy onshore winds, occasionally gusty this afternoon and
evening.

Marine As of 01:17 pm pdt Sunday... A strong north to south
pressure gradient along the california coast will maintain
moderate to strong northwesterly winds over the coastal waters
through Monday. As a result, steep wind waves will produce
hazardous conditions for small crafts. A long period southerly
swell will increase and mix with northwesterly swell by Monday
morning, gradually increasing through much of the week.

Mtr watches warnings advisories
Tngt Sca... Sf bay until 9 pm
sca... Mry bay until 9 pm
sca... Pigeon pt to pt pinos 0-10 nm until 9 pm
sca... Pt arena to pt reyes 0-10 nm
sca... Pt reyes to pigeon pt 0-10 nm
sca... Pt pinos to pt piedras blancas 0-10 nm
sca... Pt arena to pigeon pt 10-60 nm
sca... Pigeon pt to pt piedras blancas 10-60 nm
public forecast: rww
aviation: rgass
marine: rgass
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
TIBC1 - Tiburon Pier, San Francisco Bay, CA 7 mi116 min SE 5.1 60°F 1014 hPa
FTPC1 - 9414290 - San Francisco, CA 8 mi55 min W 11 G 19 56°F 59°F1014.6 hPa (-0.7)
46237 - San Francisco Bar, CA (142) 8 mi55 min 56°F5 ft
RCMC1 - 9414863 - Richmond, CA 9 mi55 min SSE 5.1 G 6 60°F 60°F1013.5 hPa (-1.0)
PPXC1 - 9414847 - Richmond (Point Potrero), CA 11 mi55 min S 4.1 G 5.1 62°F 1014.2 hPa (-0.9)
PXOC1 - 9414311 - San Francisco (Pier 1), CA 11 mi55 min WSW 8.9 G 20 59°F 1013.3 hPa (-0.7)
PXSC1 11 mi55 min 59°F 49°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 14 mi55 min WSW 19 G 21
OBXC1 14 mi55 min 57°F 50°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 14 mi55 min W 15 G 20 58°F 1014 hPa (-1.0)
AAMC1 - 9414750 - Alameda, CA 16 mi55 min W 8.9 G 13 59°F 64°F1014.7 hPa (-0.7)
LNDC1 17 mi55 min WSW 11 G 16 58°F 1014.4 hPa (-0.7)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 17 mi45 min WNW 18 G 23 53°F 51°F1015.9 hPa51°F
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 20 mi55 min WSW 6 G 12 63°F 1013.1 hPa (-1.2)
PRYC1 - 9415020 - Point Reyes, CA 23 mi55 min WNW 24 G 31 55°F1014.5 hPa (-0.6)
MZXC1 - 9415102 - Martinez-Amorco CA 26 mi55 min W 12 G 16 63°F 64°F1013.1 hPa (-1.3)51°F
PCOC1 - 9415144 - Port Chicago, CA 30 mi55 min SSW 9.9 G 17 65°F 64°F1012.7 hPa (-1.4)
RTYC1 - 9414523 - Redwood City, CA 33 mi55 min W 11 G 18 58°F 65°F1015.9 hPa (-1.0)
SFXC1 - San Francisco Bay Reserve, CA 36 mi70 min W 8.9 69°F 1013 hPa52°F
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 38 mi55 min WNW 12 G 18 65°F 1012.3 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 40 mi65 min WNW 16 G 21 54°F 54°F7 ft1016.1 hPa (-0.6)
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 46 mi45 min NW 29 G 35 54°F 1014.8 hPa49°F
46214 - Point Reyes, CA (029) 48 mi55 min 52°F9 ft

Wind History for San Francisco, CA
(wind in knots)    EDIT      (on/off)   Help
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W12
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W7
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W9
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G17

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Novato / Gnoss Field, CA18 mi80 minSW 13 G 2110.00 miFair66°F48°F52%1013.5 hPa
San Francisco, San Francisco International Airport, CA22 mi2 hrsW 18 G 2910.00 miMostly Cloudy and Breezy59°F45°F60%1015.4 hPa
Oakland, Metro Oakland International Airport, CA23 mi62 minWSW 159.00 miMostly Cloudy60°F48°F67%1015.1 hPa

Wind History from DVO (wind in knots)
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Last 24hrSW11
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SW12CalmSW11SW105
G12
NW76CalmCalm5SW74SW5S7
G12
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G18
SW13SW13SW14
G20
1 day agoSW15
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SW21SW18SW12
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SW965CalmCalmCalmNE4CalmCalmCalmCalm4Calm64SW15
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2 days agoSW16SW14
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4SW76SW5SW13NE5CalmCalmCalmCalmCalmCalmCalmCalmNE5SW844SE7E9SE9

Tide / Current Tables for Sausalito, Corps of Engineers Dock, San Francisco Bay, California
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Sausalito
Click for Map
Sun -- 12:48 AM PDT     Moonset
Sun -- 03:40 AM PDT     5.50 feet High Tide
Sun -- 05:55 AM PDT     Sunrise
Sun -- 10:42 AM PDT     -0.97 feet Low Tide
Sun -- 11:15 AM PDT     Moonrise
Sun -- 06:05 PM PDT     4.81 feet High Tide
Sun -- 08:17 PM PDT     Sunset
Sun -- 11:17 PM PDT     2.62 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
3.44.24.95.45.5542.61.1-0.1-0.8-0.9-0.50.31.42.63.74.54.84.64.13.52.92.6

Tide / Current Tables for Richardson Bay Entrance, San Francisco Bay, California Current
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Richardson Bay Entrance
Click for Map
Sun -- 12:48 AM PDT     Moonset
Sun -- 01:16 AM PDT     -0.00 knots Slack
Sun -- 05:49 AM PDT     -0.92 knots Max Ebb
Sun -- 05:55 AM PDT     Sunrise
Sun -- 08:59 AM PDT     0.01 knots Slack
Sun -- 11:15 AM PDT     Moonrise
Sun -- 11:31 AM PDT     1.07 knots Max Flood
Sun -- 03:27 PM PDT     -0.01 knots Slack
Sun -- 06:42 PM PDT     -0.43 knots Max Ebb
Sun -- 08:17 PM PDT     Sunset
Sun -- 09:26 PM PDT     0.00 knots Slack
Sun -- 11:23 PM PDT     0.58 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.40.1-0.2-0.4-0.7-0.9-0.9-0.7-0.400.611.10.90.60.2-0.1-0.3-0.4-0.4-0.3-0.10.20.6

Weather Map and Satellite Images
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wmap_P
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.
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Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for San Francisco/Monterey Bay Area, CA (17,4,5,8)
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Ground Weather Radar Station Sacramento, 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.