Thursday, May25, 2017 L-36.com


Marine Weather and Tides
Piedmont, 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 5:49AMSunset 8:22PM Thursday May 25, 2017 1:06 PM PDT (20:06 UTC) Moonrise 5:05AMMoonset 7:23PM 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 Piedmont, CA
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location: 37.85, -122.22     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
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
LNDC1 5 mi49 min SW 13 G 17 59°F 1008.8 hPa
OBXC1 7 mi49 min 57°F 52°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 7 mi49 min WSW 8 G 12 60°F 1009 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 7 mi49 min SW 11 G 16
AAMC1 - 9414750 - Alameda, CA 7 mi49 min SW 14 G 16 59°F 62°F1009.5 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 9 mi49 min SW 17 G 22 57°F 1009.1 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 10 mi67 min S 4.1 G 11 59°F 1007.9 hPa (+0.6)
PXSC1 10 mi49 min 59°F 51°F
RCMC1 - 9414863 - Richmond, CA 11 mi49 min SSW 8.9 G 16 57°F 59°F1008.9 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 12 mi55 min S 14 56°F 1009 hPa
FTPC1 - 9414290 - San Francisco, CA 13 mi49 min W 11 G 16 55°F 55°F1009.6 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 14 mi49 min W 12 G 16 58°F 1008.6 hPa
UPBC1 14 mi49 min W 14 G 18
MZXC1 - 9415102 - Martinez-Amorco CA 14 mi49 min W 12 G 17 60°F 65°F1008.7 hPa53°F
PCOC1 - 9415144 - Port Chicago, CA 17 mi49 min SSW 6 G 9.9 63°F 65°F1008.3 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 22 mi49 min WNW 13 G 16 65°F 1007.6 hPa
46237 - San Francisco Bar, CA (142) 22 mi67 min 54°F5 ft
RTYC1 - 9414523 - Redwood City, CA 24 mi49 min SSW 12 G 16 63°F 68°F1008 hPa
SFXC1 - San Francisco Bay Reserve, CA 26 mi82 min WNW 9.9 62°F 1009 hPa53°F
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 33 mi77 min SSW 9.7 G 12 52°F 54°F5 ft1009 hPa (+0.5)
PRYC1 - 9415020 - Point Reyes, CA 41 mi49 min SE 5.1 G 9.9 55°F 56°F1008.8 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 49 mi77 min SSW 7.8 G 9.7 53°F 54°F7 ft1009 hPa (+0.7)

Wind History for Oakland Middle Harbor, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Oakland, Metro Oakland International Airport, CA10 mi74 minSW 1910.00 miOvercast and Breezy64°F52°F65%1008.9 hPa
Concord, Buchanan Field, CA13 mi74 minSW 1110.00 miOvercast66°F50°F56%1007.1 hPa
Hayward, Hayward Air Terminal, CA14 mi73 minW 610.00 miOvercast66°F46°F50%1009.4 hPa
San Francisco, San Francisco International Airport, CA18 mi71 minSSW 18 G 2610.00 miPartly Cloudy and Breezy64°F48°F58%1008.9 hPa
San Carlos Airport, CA22 mi80 minSSW 11 G 1710.00 miMostly Cloudy64°F48°F56%1008.5 hPa
Livermore, Livermore Municipal Airport, CA24 mi74 minWSW 1310.00 miA Few Clouds68°F48°F49%1007.5 hPa

Wind History from OAK (wind in knots)
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Last 24hrNW11NW13NW14NW13W13NW11NW7W9W9W7SW14SW17SW14SW20
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1 day agoW11W16NW16W14NW18W17
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W17NW12NW9NW5NW10NW7NW7W9W9W11NW6W5W6NW6W4W53NW8
2 days agoNW9W13W14NW12NW14NW12NW13NW10NW9NW6NW8NW6NW7NW7NW5NW6NW6NW4NW4W5W4NW10W9NW8

Tide / Current Tables for Berkeley, San Francisco Bay, California
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Berkeley
Click for Map
Thu -- 05:51 AM PDT     Sunrise
Thu -- 06:05 AM PDT     Moonrise
Thu -- 06:23 AM PDT     -1.36 feet Low Tide
Thu -- 12:46 PM PDT     New Moon
Thu -- 01:07 PM PDT     5.01 feet High Tide
Thu -- 06:13 PM PDT     1.71 feet Low Tide
Thu -- 08:21 PM PDT     Sunset
Thu -- 08:22 PM PDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
6.65.94.52.60.8-0.6-1.3-1.2-0.40.82.23.54.654.8432.11.71.92.73.95.26.2

Tide / Current Tables for Oakland Harbor WebStreeter Street, San Francisco Bay, California Current
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Oakland Harbor WebStreeter Street
Click for Map
Thu -- 02:43 AM PDT     -1.75 knots Max Ebb
Thu -- 05:51 AM PDT     Sunrise
Thu -- 06:05 AM PDT     Moonrise
Thu -- 06:26 AM PDT     0.00 knots Slack
Thu -- 09:41 AM PDT     1.41 knots Max Flood
Thu -- 12:46 PM PDT     New Moon
Thu -- 12:59 PM PDT     -0.00 knots Slack
Thu -- 03:16 PM PDT     -1.03 knots Max Ebb
Thu -- 06:23 PM PDT     0.00 knots Slack
Thu -- 08:20 PM PDT     Sunset
Thu -- 08:22 PM PDT     Moonset
Thu -- 09:31 PM PDT     1.10 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.3-1.1-1.6-1.7-1.5-1-0.30.411.31.41.20.7-0-0.7-1-0.9-0.6-0.20.30.81.11.10.7

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 (16,3,4,5)
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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.