Thursday, September21, 2017

Marine Weather and Tides
Hercules, CA

Version 3.4
What's New / NOTES
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.
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 6:55AMSunset 7:07PM Thursday September 21, 2017 2:14 PM PDT (21:14 UTC) Moonrise 7:20AMMoonset 7:19PM Illumination 1% Phase: Waxing Crescent; Moon at 1 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- 850 Am Pdt Thu Sep 21 2017
.small craft advisory in effect from 1 pm pdt this afternoon through this evening...
Today..NW winds 5 to 15 kt...becoming W 15 to 25 kt in the afternoon.
Tonight..W winds 15 to 25 kt...decreasing to 5 to 15 kt after midnight.
Fri..W winds 5 to 15 kt.
Fri night..W winds 10 to 20 kt.
Sat..W winds 5 to 15 kt.
Sun..N winds 10 kt...becoming w.
Mon..NE winds 5 to 15 kt...becoming w.
PZZ500 850 Am Pdt Thu Sep 21 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Increasing northwest winds today as a trough moves through the region. Winds subside slightly late tonight through the weekend. Northwest swell will continue to decrease through the coming days while steep wind waves continue through Friday.

7 Day Forecast for Marine Location Near Hercules, CA
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location: 38.02, -122.29     debug

Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 212005
area forecast discussion
national weather service san francisco bay area
105 pm pdt Thu sep 21 2017

Synopsis A cool, upper level trough will dominate the western
portion of the country through the workweek maintaining cooler
than average temperatures and breezy conditions. Aside from the
potential for isolated showers offshore or near the coast Thursday,
dry weather conditions will prevail. A gradual warming trend is
then expected to begin this weekend and persist into early next

Discussion As of 1:05 pm pdt Thursday... Visible satellite
reveals a mostly sunny to sunny afternoon across the region. The
cold front that passed through overnight was able to sufficiently
mix-out the marine layer with mostly clear skies extending over
the waters as well. There have been a few areas of post-frontal
cumulus development over the santa lucias, diablo range, and
santa cruz mountains this morning that will continue this
afternoon. Can't rule out a stray sprinkle in these areas, but
aside that, dry conditions are expected across the san francisco
bay area and central coast this afternoon. High temperatures will
be in the 60s along the coast and 70s for inland areas. Compared
to climatology, these highs are about 5 to 15 degrees below what
we would normally expect for a middle late september afternoon.

Winds will be breezy again this afternoon with some gusts along
the coast or higher elevations reaching 30 to 40 mph.

Low temperatures tonight are expected to be chilly once again.

With 850 mb temperatures hovering around 4 to 6 deg c, the north
bay can expect widespread 40s once again for Friday morning some
locations dipping to the mid upper 30s. On Friday we'll begin to
see a gradual and continuous warming trend as an upper level ridge
begins to build in the eastern pacific. Expect Friday's highs to
be about 2 to 5 degrees warmer than today with some communities in
the interior east bay climbing to the upper 70s. Tomorrow also
marks the autumnal equinox, which will occur at 1:02 pm pdt.

One more seasonably cool night is forecast on Saturday morning
with lows in the 40s and 50s. The building pacific ridge will
allow for 500 mb heights to continue to rise through the afternoon
and even into next week. Consequently, we'll watch temperatures
go from below normal back to above normal by Sunday with
widespread 80s emerging for inland areas and even parts of the
south bay. The warming will continue into early next week with 90s
starting to appear back on the map. With the north to
northeasterly flow, do expect drying conditions with decreasing
afternoon relative humidities by the second half of the weekend
and early next week. This will lead to increased fire weather
concerns across parts of central and northern california.

Aviation As of 10:55 am pdt Thursday for 18z tafs...

postfrontal environment bringing well mixed marine layer and
widespreadVFR CIGS this morning. Unstable postfrontal airmass is
firing some shallow convection over the higher terrain over the
south bay, east bay, santa lucia mountains and santa cruz
mountains. A few sprinkles possible today in these areas if
convection deepens, however this is unlikely. Otherwise, breezy
onshore winds forecast today, with sust winds 10-20 kt, with peak
gusts 20 to 30 kt. Some high clouds will arrive late today. Dirty
feed of sct-bkn AOA 2000-4000 ft agl will bring intermittent MVFR
cigs in a window from 10-18z fri, depending on location. High
confidence for today, low confidence on exact details for tomorrow
mornings dirty feed.

Vicinity of ksfo...VFR. Sustained onshore winds 15 to 20 kt, gusts
25 to 30 kt. MVFR CIGS possible Fri morning from 12-17z with dirty
onshore feed as trough shifts through.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR. Shallow convection distant south
and east with few-sct at 3000 to 5000 ft agl. Breezy onshore winds
10 to 15 kt with gusts up to 20kt possible, locally stronger along
the immediate coastline. Intermittent MVFR CIGS posbl 12 to 18z
fri W sct-bkn from 2000-4000 ft.

Marine As of 1:03 pm pdt Thursday... Increasing northwest winds
today as a trough moves through the region. Winds subside
slightly late tonight through the weekend. Northwest swell will
continue to decrease through the coming days while steep wind
waves continue through Friday.

Mtr watches warnings advisories
Tngt Sca... Sf bay until 9 pm
sca... Mry bay until 9 pm
sca... Pt arena to pt reyes 0-10 nm until 9 pm
sca... Pt reyes to pigeon pt 0-10 nm until 9 pm
sca... Pigeon pt to pt pinos 0-10 nm until 9 pm
sca... Pt pinos to pt piedras blancas 0-10 nm until 9 pm
sca... Pigeon pt to pt piedras blancas 10-60 nm until 9 pm
sca... Pt arena to pigeon pt 10-60 nm
public forecast: rowe
aviation: drp
marine: drp
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 3 mi45 min SW 4.1 G 5.1 65°F 1011.3 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 9 mi45 min WNW 8 G 11 65°F 68°F1011.7 hPa37°F
RCMC1 - 9414863 - Richmond, CA 9 mi45 min S 7 G 8.9 65°F 66°F1011.7 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 9 mi45 min SSW 9.9 G 13 66°F 1012.2 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 12 mi53 min SE 8.9 64°F 1012 hPa
PCOC1 - 9415144 - Port Chicago, CA 14 mi45 min WNW 5.1 G 6 65°F 68°F1011.4 hPa
OKXC1 - 9414776 - Oakland (Berth 34), CA 15 mi45 min W 11 G 13 63°F 1012.1 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 15 mi45 min W 12 G 14
OBXC1 15 mi45 min 63°F 49°F
PXSC1 16 mi45 min 64°F 48°F
PXOC1 - 9414311 - San Francisco (Pier 1), CA 16 mi45 min W 11 G 16 63°F 1011.2 hPa
LNDC1 16 mi45 min W 8.9 G 13 64°F 1012.1 hPa
FTPC1 - 9414290 - San Francisco, CA 17 mi45 min W 7 G 12 61°F 63°F1012.6 hPa
AAMC1 - 9414750 - Alameda, CA 17 mi45 min W 8.9 G 12 65°F 67°F1012.7 hPa
SFXC1 - San Francisco Bay Reserve, CA 19 mi90 min SW 7 68°F 1011 hPa45°F
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 21 mi45 min NNW 7 G 8.9 67°F 1011.1 hPa
46237 - San Francisco Bar, CA (142) 24 mi45 min 59°F5 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 34 mi85 min NW 18 G 21 57°F 56°F7 ft1012.9 hPa (+0.0)
RTYC1 - 9414523 - Redwood City, CA 36 mi45 min W 13 G 17 63°F 69°F1012.2 hPa
PRYC1 - 9415020 - Point Reyes, CA 36 mi45 min WNW 23 G 28 63°F 55°F1012.5 hPa

Wind History for Union Pacific Rail Road Bridge (UPRR), CA
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1 day
2 days

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Concord, Buchanan Field, CA13 mi82 minS 710.00 miPartly Cloudy69°F41°F36%1010.5 hPa
Napa, Napa County Airport, CA13 mi81 minSW 510.00 miA Few Clouds71°F39°F31%1010.6 hPa
Novato / Gnoss Field, CA16 mi80 minVar 3 G 1410.00 miFair72°F39°F31%1011.8 hPa
Oakland, Metro Oakland International Airport, CA22 mi82 minW 810.00 miA Few Clouds66°F43°F43%1012.4 hPa
Petaluma Municipal Airport, CA23 mi80 minW 1210.00 miA Few Clouds70°F42°F38%1011.5 hPa

Wind History from APC (wind in knots)
Last 24hrW17
1 day agoSW14SW11W15W20
2 days agoW15

Tide / Current Tables for Hercules, Refugio Landing, San Pablo Bay, California
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Thu -- 01:54 AM PDT     6.42 feet High Tide
Thu -- 06:56 AM PDT     Sunrise
Thu -- 08:19 AM PDT     Moonrise
Thu -- 08:25 AM PDT     0.71 feet Low Tide
Thu -- 02:23 PM PDT     6.46 feet High Tide
Thu -- 07:07 PM PDT     Sunset
Thu -- 08:18 PM PDT     Moonset
Thu -- 08:51 PM PDT     0.78 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

Tide / Current Tables for Davis Point, California Current
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Davis Point
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Thu -- 12:10 AM PDT     1.52 knots Max Flood
Thu -- 03:29 AM PDT     -0.00 knots Slack
Thu -- 06:56 AM PDT     Sunrise
Thu -- 07:29 AM PDT     -2.02 knots Max Ebb
Thu -- 08:19 AM PDT     Moonrise
Thu -- 10:09 AM PDT     0.00 knots Slack
Thu -- 12:25 PM PDT     1.55 knots Max Flood
Thu -- 04:02 PM PDT     -0.00 knots Slack
Thu -- 07:07 PM PDT     Sunset
Thu -- 08:07 PM PDT     -1.93 knots Max Ebb
Thu -- 08:18 PM PDT     Moonset
Thu -- 10:42 PM PDT     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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

GOES Local Image of CentralWestCoast    EDIT

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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weather_mapweather_map weather_map

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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 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 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.