Thursday, May25, 2017 L-36.com


Marine Weather and Tides
Tamalpais-Homestead Valley, CA

Version 3.4
What's New / NOTES
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 5:50AMSunset 8:24PM Thursday May 25, 2017 11:22 AM PDT (18:22 UTC) Moonrise 5:06AMMoonset 7:24PM Illumination 0% Phase: New Moon; Moon at 0 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 San Francisco Bay North Of The Bay Bridge- 830 Am Pdt Thu May 25 2017
.small craft advisory in effect from 3 pm pdt this afternoon through this evening...
Today..SW winds 10 to 20 kt...increasing to 15 to 25 in the afternoon. Gusts up to 35 kt in the afternoon.
Tonight..SW winds 15 to 25 kt...decreasing to 5 to 15 kt after midnight. Patchy fog after midnight.
Fri..SW winds 5 to 15 kt. Patchy fog in the morning.
Fri night..W winds 5 to 15 kt. Patchy fog after midnight.
Sat..SW winds 10 to 20 kt. Patchy fog in the morning.
Sun..SW winds 5 to 15 kt.
Memorial day..SW winds 10 kt.
PZZ500 830 Am Pdt Thu May 25 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Increasing south to southwest winds are expected near the coastline and across the bays today...strongest along the big sur coast. These winds will generate steep fresh swell in the vicinity. Otherwise...light seas. High pressure will redevelop over the eastern pacific just prior to the memorial day weekend bringing a return to more typical afternoon and evening onshore winds to the coastal waters and bays.

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 251750
afdmtr
area forecast discussion
national weather service san francisco bay area
1050 am pdt Thu may 25 2017

Synopsis Seasonably cool today into Friday with a deep marine
layer near the coast. Seasonable temperatures on Saturday should
trend warmer inland by Sunday and memorial day Monday. Aside from
the isolated coastal drizzle, dry weather forecast through the
next 7 to 10 days.

Discussion As of 08:00 am pdt Thursday... Only made minor
tweaks to the short-term forecast with sky cover. Satellite
reveals an extensive marine layer intruding well inland through
the delta pushing up against the sierra foothills. Fort ord
profiler indicates the marine layer depth has steadily deepened
over the past 24 hours to over 3500 ft this morning and is
approaching 4000 ft. There have also been some reports of drizzle
or even light rain associated with the low clouds in the north
bay. Santa rosa ASOS has reported several one-hundreds of an inch
since midnight.

Upper level low continues to approach the central california coast
and will help to maintain the downward trend in afternoon highs
through the end of the work week. MAX temps for many inland
locations will be anywhere from 5 to perhaps as much as 15 degrees
below normal for late may. The cool weather will be short-lived,
however, as a ridge will be quick to build over the west coast for
the holiday weekend with temperatures rebounding back to normal or
even several degrees above normal. Guidance suggests that the
southern salinas valley may return back to low 90s as early as
Sunday. While the inland areas ride their temperature roller
coaster, coastal locations influenced by low clouds will struggle
to see temperatures change any more than 5 degrees over the
forecast period. The only chance for precipitation over the next 7
days will be for coastal areas that may see isolated drizzle or
light rain.

Prev discussion As of 3:23 am pdt Thursday... Profiler data shows
the marine layer has deepened in excess of 3000 feet with cooler
air aloft keeping the inversion weak. This has allowed deep inland
penetration of marine clouds with a finger now pushing out into
the delta while nearly the entire north bay is completely
inundated as well. Onshore gradient is only 2 mb from sfo to sac
but gusts from 20 to 30 kt are showing up at angel island, concord
and travis which is a sure sign of another cool day for inland
areas with highs struggling to reach 70. In addition to the
extensive cloud cover and onshore push the models continue to show
some drizzle along the coast from half moon bay to big sur this
morning. Forecast grids will continue to show some patchy drizzle
this morning as the Sun comes up, just enough to wet the surfaces
but only expecting trace amounts.

The upper pattern wont change too much on Friday with cyclonic
flow aloft and onshore flow at the surface keeping temps on the
cool side of normal.

As is typical this time of year day to day changes can be hard to
nail down as the subtle marine perturbations can drive the daily
patterns. However the general trend of the holiday weekend shows
near normal temperatures on Saturday then climbing back to above
normal for inland areas on Saturday and Sunday as high pressure
briefly rebuilds. All in all it looks to be a nice holiday weekend
with dry conditions and no excessively hot inland weather. Longer
range trends portend a dry and seasonable pattern through much of
next week as we head into june.

Aviation As of 10:37 am pdt Thursday... Deep marine intrusion
continues over the region with south southwest winds pushing lower
clouds over the coastal ranges. Bases are lifting at times,
especially inland away from the coast. Do expect some inland areas
to see clouds scattering out briefly this afternoon, while coastal
and potentially north bay terminals remain under a cloud deck
through much of the day. Stratus returns late this evening and
will likely lower overnight into early Friday morning. Otherwise,
breezy to occasionally gusty west to southwest winds, especially
along the coast in the afternoon and evening.

Vicinity of ksfo... Bkn cloud deck over the terminal for much of
the morning is beginning to scatter out and should give way to
vfr CIGS by 1830z-1900z. Breezy and gusty southerly winds are
forecast to become more westerly by the early afternoon. Winds
diminish slightly late this evening with stratus deck returning
between 0500z-0700z. Similar burn-off time likely on Friday.

Moderate confidence.

Sfo bridge approach... Bkn cloud deck may linger over the approach
through 20z. Otherwise, similar to ksfo.

Monterey bay terminals... MVFR CIGS through the day with cloud
deck potentially scattering out or lifting above 3kft at times
this afternoon. Otherwise, breezy onshore winds are expected
through the afternoon and evening. Winds diminish late in the
evening with lowering CIGS likely overnight.

Moderate confidence.

Marine As of 10:37 am pdt Thursday... Increasing south to
southwest winds are expected near the coastline and across the
bays today, strongest along the big sur coast. These winds will
generate steep fresh swell in the vicinity. Otherwise, light
seas. High pressure will redevelop over the eastern pacific just
prior to the memorial day weekend bringing a return to more
typical afternoon and evening onshore winds to the coastal waters
and bays.

Mtr watches warnings advisories
Tday Sca... Mry bay
sca... Pt pinos to pt piedras blancas 0-10 nm
sca... Pt arena to pigeon pt 10-60 nm
sca... Sf bay from 3 pm
public forecast: rowe rww
aviation: rgass
marine: rgass
visit us at

Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
TIBC1 - Tiburon Pier, San Francisco Bay, CA 7 mi75 min SE 5.1 55°F 1009 hPa
FTPC1 - 9414290 - San Francisco, CA 8 mi64 min WSW 7 G 14 55°F 57°F1008.9 hPa
46237 - San Francisco Bar, CA (142) 8 mi82 min 54°F5 ft
RCMC1 - 9414863 - Richmond, CA 9 mi64 min SSW 13 G 18 55°F 59°F1008.4 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 11 mi64 min SW 18 G 20 56°F 1008.6 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 11 mi70 min N 4.1 G 8 58°F 1007.4 hPa
PXSC1 11 mi64 min 58°F 51°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 14 mi64 min SSW 13 G 15
OBXC1 14 mi64 min 58°F 51°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 14 mi64 min SSW 9.9 G 13 60°F 1008.4 hPa
AAMC1 - 9414750 - Alameda, CA 16 mi64 min SSW 12 G 17 58°F 62°F1008.9 hPa
LNDC1 17 mi70 min SW 11 G 15 58°F 1008.4 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 17 mi92 min SSW 7.8 G 7.8 51°F 53°F5 ft1008.7 hPa (+1.2)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 20 mi64 min WSW 12 G 15 58°F 1008.2 hPa
PRYC1 - 9415020 - Point Reyes, CA 23 mi64 min SE 6 G 14 54°F 56°F1008.1 hPa
UPBC1 26 mi64 min W 6 G 14
MZXC1 - 9415102 - Martinez-Amorco CA 26 mi64 min SW 8 G 11 60°F 65°F1008.4 hPa50°F
PCOC1 - 9415144 - Port Chicago, CA 30 mi58 min SW 8.9 G 14 60°F 64°F1007.9 hPa
RTYC1 - 9414523 - Redwood City, CA 33 mi64 min SSW 7 G 13 61°F 68°F1007.8 hPa
SFXC1 - San Francisco Bay Reserve, CA 36 mi97 min W 8.9 59°F 1008 hPa52°F
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 38 mi64 min WNW 14 G 17 62°F 1007.4 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 40 mi92 min SW 7.8 G 9.7 52°F 54°F7 ft1008.6 hPa (+1.1)
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 46 mi42 min E 3.9 G 5.8 51°F 51°F1008.5 hPa49°F
46214 - Point Reyes, CA (029) 48 mi82 min 52°F9 ft

Wind History for San Francisco, CA
(wind in knots)    EDIT      (on/off)   Help
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Novato / Gnoss Field, CA18 mi27 minVar 410.00 miOvercast61°F48°F63%1008.5 hPa
San Francisco, San Francisco International Airport, CA22 mi26 minSSW 20 G 2510.00 miPartly Cloudy and Breezy63°F48°F60%1008.3 hPa
Oakland, Metro Oakland International Airport, CA23 mi29 minSW 1510.00 miOvercast64°F52°F65%1008.5 hPa

Wind History from DVO (wind in knots)
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Last 24hrNE9N9N11S9SW9
G15
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W6CalmCalmSW4SW5W6W7W4SW6CalmSW65CalmCalm
1 day ago3N7N10N9NW7
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N12N12N10
G17
N9N11N6NW6NW4NW7N6SE5CalmCalmCalmSW5SW5CalmN8
2 days agoCalmCalm334N12N12N10N12N10N10N10N9--N8N8N9N6N8N7NW5N7N44

Tide / Current Tables for Sausalito, Corps of Engineers Dock, San Francisco Bay, California
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Sausalito
Click for Map
Thu -- 05:52 AM PDT     Sunrise
Thu -- 06:06 AM PDT     Moonrise
Thu -- 06:06 AM PDT     -1.36 feet Low Tide
Thu -- 12:46 PM PDT     New Moon
Thu -- 12:56 PM PDT     4.81 feet High Tide
Thu -- 05:56 PM PDT     1.71 feet Low Tide
Thu -- 08:21 PM PDT     Sunset
Thu -- 08:23 PM PDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
6.35.43.92.10.3-0.9-1.4-1.1-0.212.43.64.54.84.53.72.721.72.134.15.36.2

Tide / Current Tables for Richardson Bay Entrance, San Francisco Bay, California Current
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Richardson Bay Entrance
Click for Map
Thu -- 01:18 AM PDT     -1.17 knots Max Ebb
Thu -- 04:16 AM PDT     0.00 knots Slack
Thu -- 05:52 AM PDT     Sunrise
Thu -- 06:06 AM PDT     Moonrise
Thu -- 06:40 AM PDT     1.41 knots Max Flood
Thu -- 10:25 AM PDT     -0.00 knots Slack
Thu -- 12:46 PM PDT     New Moon
Thu -- 01:51 PM PDT     -0.68 knots Max Ebb
Thu -- 04:13 PM PDT     0.00 knots Slack
Thu -- 06:30 PM PDT     1.10 knots Max Flood
Thu -- 08:21 PM PDT     Sunset
Thu -- 08:23 PM PDT     Moonset
Thu -- 09:44 PM PDT     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-1-1.2-1.1-0.7-0.20.61.31.41.20.80.3-0.2-0.5-0.6-0.7-0.5-0.10.511.10.80.4-0.1-0.5

Weather Map and Satellite Images
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Weather Map
wmap_P
IR Satellite Image from GEOS
west_satellite

GOES Local Image of CentralWestCoast    EDIT
Geos

Wind Forecast for San Francisco/Monterey Bay Area, CA (14,3,4,5)
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Ground Weather Radar Station Sacramento, CA
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weather_mapweather_map weather_map

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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.