Wednesday, May23, 2018

Marine Weather and Tides
Hercules, 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 5:50AMSunset 8:21PM Wednesday May 23, 2018 3:52 AM PDT (10:52 UTC) Moonrise 1:34PMMoonset 1:51AM Illumination 61% Phase: Waxing Gibbous; Moon at 8 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- 231 Am Pdt Wed May 23 2018
.small craft advisory in effect from 9 am pdt this morning through this afternoon...
Today..SW winds 10 to 20 kt...increasing to 15 to 25 kt before noon. Areas of drizzle in the morning.
Tonight..W winds 10 to 20 kt.
Thu..SW winds 10 to 20 kt.
Thu night..SW winds 10 to 20 kt. Slight chance of showers after midnight.
Fri..W winds 5 to 15 kt. Slight chance of showers.
Sat..SW winds 10 kt.
Sun..SW winds 10 kt.
PZZ500 231 Am Pdt Wed May 23 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Light northwest winds will prevail through midweek for the coastal waters. Winds are expected to increase through the golden gate gap, around angel island, and in the west delta by mid morning into mid afternoon today. Thus, a small craft advisory is in place for the northern san francisco bay and west delta for persistent wind gusts over 20 knots. By Thursday morning, winds are forecast to turn southerly as a weak low pressure system approaches from the west. This low will bring a chance of showers Thursday and Friday. Long period southwest swell will persist with a shorter period northwest swell through the week, decreasing by 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 231012
area forecast discussion
national weather service san francisco bay area
312 am pdt Wed may 23 2018

Synopsis Cool weather and morning low clouds will continue
through most of the week with inland temperatures remaining below
normal for this time of year as a deep marine layer continues to
influence the region. An upper level low will move through the
area late Thursday into Friday bringing a chance of showers to
most of the area. Showers will end by Saturday morning before a
warming trend brings inland temperatures back to near seasonal
normals by Sunday.

Discussion As of 3:10 am pdt Wednesday... Deep marine layer
near 3000 feet and strong east-west onshore flow has allowed
stratus to spread well inland this morning. Many places around the
cwa are reporting measurable drizzle. An upper level low over
nevada will move slowly NE today with a weak transient ridge
moving over the state later today. This may compress the marine
layer a little bit but temperatures will still be cool with inland
temperatures remaining 5 to 10 degrees below normal. Another
breezy day is expected due to the persistently strong onshore

Cool temperatures continue the rest of the week as another upper
low is approaching from the west. Models in agreement in moving
this low through the bay area late Thursday and Friday. A frontal
system is forecast to dissipate as it nears the coast precip but
there will be a chance of showers in the sfo bay area Thursday
night through Friday afternoon with a slight chance of showers
south of there. Coastal low clouds should finally mix out on

The low moves through Friday night and shower chances diminish.

A warming trend takes place this weekend as upper level ridge
builds off the california and oregon coast. Temperatures should
return to near normal conditions by Sunday or memorial day. There
may even be some offshore flow as a surface ridge builds into the
washington and oregon coast.

Aviation As of 10:55 pm pdt Tuesday for 06z tafs... A deep
marine layer and a moderately strong pressure gradient persists
across the region spreading widespread low clouds inland. MVFR to
borderline ifr CIGS expected to continue through tonight and
through Tuesday morning. Onshore flow will continue to diminish

Vicinity of ksfo... A deep marine layer will maintain MVFR cigs
across area terminals through much of the forecast period.

Temporary clearing possible Tuesday afternoon. Onshore winds
around 10 kt will continue through tonight. Winds will ramp up
again Tuesday afternoon to around 15 kt with occasional higher
gusts possible.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... MVFR ifr CIGS will continue across area
terminals through tonight. Temporary clearing possible Tuesday
afternoon evening. Light onshore winds will continue through
tonight. Winds will ramp up again Tuesday afternoon to around 10
to 15 kt.

Marine As of 9:02 pm pdt Tuesday... Generally light northwest
winds are expected this evening and overnight, though locally
breezy conditions are possible near the golden gate and angel
island. Winds will become southerly by Thursday morning as a weak
low pressure system approaches from the west. This low will bring
a chance of showers Thursday through Friday night. A long period
southwest swell will persist with a shorter period northwest swell
through the week.

Mtr watches warnings advisories
Tday Sca... Sf bay from 9 am until 3 pm
public forecast: W pi
aviation: cw
marine: cw rowe
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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 mi53 min W 11 G 15 57°F 1011.7 hPa (-0.4)
RCMC1 - 9414863 - Richmond, CA 9 mi53 min SW 5.1 G 8.9 1012.2 hPa (-0.4)
PPXC1 - 9414847 - Richmond (Point Potrero), CA 9 mi53 min SW 8 G 9.9 56°F 1012.7 hPa (-0.5)
MZXC1 - 9415102 - Martinez-Amorco CA 9 mi53 min SW 11 G 18 56°F 64°F1011.9 hPa56°F
PCOC1 - 9415144 - Port Chicago, CA 14 mi53 min WSW 15 G 19 55°F 64°F1011.6 hPa (-0.5)
OBXC1 15 mi53 min 55°F 54°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 15 mi53 min SW 7 G 8.9 54°F 1012.7 hPa (-0.5)
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 15 mi53 min SW 8 G 8.9
PXOC1 - 9414311 - San Francisco (Pier 1), CA 16 mi53 min SW 5.1 G 9.9 53°F 1011.7 hPa (-0.5)
LNDC1 16 mi53 min SW 6 G 8 55°F 1012.6 hPa (-0.6)
PXSC1 16 mi53 min 55°F 55°F
FTPC1 - 9414290 - San Francisco, CA 17 mi53 min SSW 2.9 G 6 1012.9 hPa (-0.5)
AAMC1 - 9414750 - Alameda, CA 17 mi53 min SW 7 G 8.9 1012.9 hPa (-0.6)
SFXC1 - San Francisco Bay Reserve, CA 19 mi68 min WNW 12 56°F 1011 hPa52°F
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 21 mi77 min W 12 G 19 56°F 1010.9 hPa
46237 - San Francisco Bar, CA (142) 24 mi53 min 55°F4 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 34 mi43 min WSW 7.8 G 9.7 52°F 51°F1013.2 hPa
RTYC1 - 9414523 - Redwood City, CA 36 mi53 min W 6 G 9.9 55°F 65°F1013.4 hPa (-0.5)
PRYC1 - 9415020 - Point Reyes, CA 36 mi53 min W 7 G 11 50°F1012.2 hPa (-0.5)

Wind History for Union Pacific Rail Road Bridge (UPRR), CA
(wind in knots)    EDIT      (on/off)   Help
1 day
2 days

Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Concord, Buchanan Field, CA13 mi60 minWSW 1010.00 miOvercast57°F50°F78%1010.7 hPa
Napa, Napa County Airport, CA13 mi2 hrsW 810.00 miOvercast56°F51°F84%1011.2 hPa
Novato / Gnoss Field, CA16 mi78 minWSW 4 G 1110.00 miOvercast55°F51°F88%1012.2 hPa
Oakland, Metro Oakland International Airport, CA22 mi60 minSW 97.00 miOvercast54°F52°F93%1012.8 hPa
Petaluma Municipal Airport, CA23 mi78 minW 34.00 miFog/Mist54°F53°F100%1012.2 hPa

Wind History from APC (wind in knots)
Last 24hrW5W4S11S9S12S12
1 day agoCalmCalmCalmCalmCalmSW5SW10SW10S10S12S15S18S18S15S15S14S13S13
2 days agoW9W12W8W9W8W7W4S10S10SW12S16

Tide / Current Tables for Hercules, Refugio Landing, San Pablo Bay, California
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Wed -- 02:50 AM PDT     Moonset
Wed -- 03:20 AM PDT     1.83 feet Low Tide
Wed -- 05:52 AM PDT     Sunrise
Wed -- 08:21 AM PDT     5.00 feet High Tide
Wed -- 02:33 PM PDT     Moonrise
Wed -- 03:12 PM PDT     0.18 feet Low Tide
Wed -- 08:19 PM PDT     Sunset
Wed -- 09:44 PM PDT     6.23 feet High 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
Click for Map
Wed -- 02:13 AM PDT     -1.81 knots Max Ebb
Wed -- 02:50 AM PDT     Moonset
Wed -- 04:46 AM PDT     0.00 knots Slack
Wed -- 05:52 AM PDT     Sunrise
Wed -- 06:49 AM PDT     1.05 knots Max Flood
Wed -- 09:58 AM PDT     -0.00 knots Slack
Wed -- 02:14 PM PDT     -2.06 knots Max Ebb
Wed -- 02:33 PM PDT     Moonrise
Wed -- 05:03 PM PDT     0.00 knots Slack
Wed -- 08:05 PM PDT     1.55 knots Max Flood
Wed -- 08:19 PM PDT     Sunset
Wed -- 11:51 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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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 (6,6,7,8)
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Ground Weather Radar Station Sacramento, CA
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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.