Monday, September25, 2017 L-36.com


Marine Weather and Tides
Piedmont, 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 6:58AMSunset 7:00PM Monday September 25, 2017 11:54 AM PDT (18:54 UTC) Moonrise 11:11AMMoonset 9:39PM Illumination 26% Phase: Waxing Crescent; Moon at 5 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- 832 Am Pdt Mon Sep 25 2017
Today..W winds 5 kt...becoming nw 5 to 15 kt in the afternoon.
Tonight..W winds 5 to 15 kt.
Tue..NE winds 10 kt.
Tue night..NW winds 5 kt.
Wed..NE winds 5 kt...becoming sw.
Thu..W winds 10 kt.
Fri..SW winds 10 kt.
PZZ500 832 Am Pdt Mon Sep 25 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Moderate northwesterly winds will continue over the northern outer waters as high pressure sits over the eastern pacific and a thermal trough resides over california. Winds will begin to decrease on Tuesday as the trough shifts towards the coast.

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 251730
afdmtr
area forecast discussion
national weather service san francisco bay area
1030 am pdt Mon sep 25 2017

Synopsis Warm offshore pattern will continue at least through
Wednesday with mild nights and breezy winds in the hills. Some
coastal cooling possible by Thursday with a gradual cooling trend
back to more seasonable temperatures by next weekend but with a
continued dry weather pattern.

Discussion As of 08:35 am pdt Monday... Mainly clear skies
prevail over the region again this morning as high pressure builds
over the eastern pacific. With warming conditions aloft, surface
temperatures are generally running a few degrees warmer compared
to 24 hours ago along with slightly lower relative humidity
values. This is setting the stage for the warming trend to
continue today with most areas a few to as much as 8 degrees
warmer than yesterday. With this said, the ongoing forecast for
today remains on track and no updates are needed at this time.

Please see the previous forecast discussion below for additional
details.

Prev discussion As of 3:37 am pdt Monday... Classic september
offshore weather pattern is forecast for much of the upcoming work
week. Synoptic pattern features northerly wind flow aloft with a
thermal trough at the surface over coastal california while the
center of the surface high remains well offshore. Current surface
gradients include 4 mb northerly down the coast with about 6 mb
offshore from the nevada deserts towards the coast. This is
occurring with mostly clear skies to start the day. Winds in the
hills are generally light this morning with lows from the mid 50s
to mid 60s on average, mildest where the winds are strongest.

Humidity values remain under 30 percent for many of the hill
locations so red flag warnings will continue for the north and
east bay hills through at least Wednesday.

Expect warm to locally hot weather today through Wednesday under
offshore wind regime. However, low dewpoints will keep heat
indices and impacts to a minimum along with longer early fall
nights allowing for night time cooling, even for buildings without
ac. To be clear the magnitude and overall set-up of this heat
event is not nearly as extreme as what was observed at the start
of sept.

For tonight, the models are showing another burst of gusty
northeast east winds, strongest over the napa and east bay hills.

Further drying of the airmass will persist right through Tuesday.

The combination of hot day time temps, dry offshore winds and
prolonged periods of low humidity values has prompted the red
flag warning to run through weds. No appreciable rain has fallen
and fuels remain critically dry so use extra precaution with any
ignitions sources including nigh-time warming fires.

By weds we'll lose some of the offshore adiabatic warming but no
strong onshore return is forecast so will likely squeeze another
warm to hot today, even near the coast. By Thursday the ridge will
finally weaken and allow for some cooling but temperatures to
remain on the warm side of normal through late week and likely
into the weekend as well with no rain in sight.

Aviation As of 10:30 am pdt Monday... For 18z tafs. Satellite
imagery this morning showing clear skies across the region
bringingVFR conditions to all sites. Aside from a few high
clouds, expecting relatively clear skies through the period.

Winds generally light with westerly winds 10-15 kt expected this
afternoon.

Vicinity of ksfo...VFR. West winds to 15 kt this afternoon.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR with mostly clear skies. Not
expecting any stratus through the period. Generally light winds
this morning with westerly winds this afternoon at around 10 kt.

Fire weather As of 3:37 am pdt Monday... Red flag warnings in
effect through weds afternoon for the north and east bay hills.

Temps will warm up and rh values dry out again today. Expect
stronger offshore winds in the hills tonight with continued
lowering of humidity into Tuesday. Models show another burst of
gusty northeast winds in the north and east bay hills Tuesday
night into early weds. Winds will finally ease by weds afternoon
but by then the fuels will be very dry with low humidity and
likely the hottest day of the week with widespread readings into
the upper 80s and 90s. We are near the peak of bay area fire
season and this is a classic critical fire weather pattern.

Marine As of 08:32 am pdt Monday... Moderate northwesterly
winds will continue over the northern outer waters as high
pressure sits over the eastern pacific and a thermal trough
resides over california. Winds will begin to decrease on Tuesday
as the trough shifts towards the coast.

Mtr watches warnings advisories
Tday Sca... Pt arena to pigeon pt 10-60 nm
public forecast: rgass
aviation: as
marine: as
fire weather: rww
visit us at

Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
LNDC1 5 mi55 min SW 5.1 G 6 68°F 1014.2 hPa (+0.0)
OBXC1 7 mi55 min 65°F 56°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 7 mi55 min SSW 6 G 7
OKXC1 - 9414776 - Oakland (Berth 34), CA 7 mi55 min SW 5.1 G 6 67°F 1014.2 hPa (-0.3)
AAMC1 - 9414750 - Alameda, CA 7 mi55 min SSW 2.9 G 4.1 66°F 67°F1014.8 hPa (+0.0)
PPXC1 - 9414847 - Richmond (Point Potrero), CA 9 mi55 min SSW 2.9 G 4.1 70°F 1014.6 hPa (+0.0)
PXOC1 - 9414311 - San Francisco (Pier 1), CA 10 mi55 min E 8 G 8.9 64°F 1013.1 hPa (-0.3)
PXSC1 10 mi55 min 66°F 59°F
RCMC1 - 9414863 - Richmond, CA 11 mi55 min S 1.9 G 4.1 65°F 64°F1014.1 hPa (+0.0)
FTPC1 - 9414290 - San Francisco, CA 13 mi55 min NW 1.9 G 4.1 63°F 62°F1014.6 hPa (+0.0)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 14 mi55 min W 2.9 G 5.1 67°F 1013.8 hPa (-0.4)
MZXC1 - 9415102 - Martinez-Amorco CA 14 mi55 min Calm G 2.9 68°F 67°F1014.3 hPa (-0.4)56°F
PCOC1 - 9415144 - Port Chicago, CA 17 mi55 min NE 5.1 G 6 70°F 67°F1014 hPa (-0.3)
46237 - San Francisco Bar, CA (142) 22 mi55 min 61°F3 ft
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 22 mi55 min WNW 2.9 G 4.1 71°F 1013.9 hPa (+0.0)
RTYC1 - 9414523 - Redwood City, CA 24 mi55 min Calm G 1.9 69°F 67°F1013.8 hPa (+0.0)
SFXC1 - San Francisco Bay Reserve, CA 26 mi70 min WSW 2.9 73°F 1014 hPa49°F
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 33 mi65 min NW 7.8 G 9.7 58°F 59°F5 ft1014.5 hPa (+0.4)
PRYC1 - 9415020 - Point Reyes, CA 41 mi55 min E 1 G 1.9 69°F 57°F1014 hPa (+0.0)
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 49 mi65 min NW 7.8 G 9.7 61°F 62°F6 ft1013.9 hPa (+0.3)

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 mi62 minS 510.00 miA Few Clouds68°F48°F51%1014.2 hPa
Concord, Buchanan Field, CA13 mi62 minN 010.00 miFair76°F39°F26%1012.6 hPa
Hayward, Hayward Air Terminal, CA14 mi61 minWSW 510.00 miFair71°F42°F35%1015 hPa
San Francisco, San Francisco International Airport, CA18 mi59 minE 410.00 miA Few Clouds68°F55°F63%1014 hPa
San Carlos Airport, CA22 mi65 minN 010.00 miA Few Clouds70°F53°F57%1014.6 hPa
Livermore, Livermore Municipal Airport, CA24 mi62 minSW 310.00 miFair73°F39°F30%1013.7 hPa

Wind History from OAK (wind in knots)
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Last 24hrW53S6W13W15W16NW7NW6NW6NW5W4CalmCalmCalmNE4NE4NE3NE3NE3NE3E33S4S5
1 day agoNW11W13W13W16W16W16W12NW8NW8W5NW3CalmE3NE6NE3NE3NE3NE3E3E3NE3SE44SW5
2 days agoSW4SW5W8W10W13W11W9W11W9NW4NE3E3CalmE4E3NE3E3NE3NE4NE3NE4CalmS3S7

Tide / Current Tables for Berkeley, San Francisco Bay, California
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Berkeley
Click for Map
Mon -- 04:29 AM PDT     4.51 feet High Tide
Mon -- 06:59 AM PDT     Sunrise
Mon -- 09:58 AM PDT     2.53 feet Low Tide
Mon -- 12:10 PM PDT     Moonrise
Mon -- 03:52 PM PDT     5.38 feet High Tide
Mon -- 07:00 PM PDT     Sunset
Mon -- 10:39 PM PDT     Moonset
Mon -- 10:48 PM PDT     0.88 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.72.63.44.14.54.54.23.63.12.72.52.73.23.94.75.25.45.14.43.52.41.610.9

Tide / Current Tables for Oakland Harbor WebStreeter Street, San Francisco Bay, California Current
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Oakland Harbor WebStreeter Street
Click for Map
Mon -- 01:13 AM PDT     0.85 knots Max Flood
Mon -- 04:30 AM PDT     -0.00 knots Slack
Mon -- 06:44 AM PDT     -0.70 knots Max Ebb
Mon -- 06:59 AM PDT     Sunrise
Mon -- 10:10 AM PDT     0.00 knots Slack
Mon -- 12:10 PM PDT     Moonrise
Mon -- 01:09 PM PDT     0.62 knots Max Flood
Mon -- 03:59 PM PDT     -0.00 knots Slack
Mon -- 07:00 PM PDT     Sunset
Mon -- 07:01 PM PDT     -1.06 knots Max Ebb
Mon -- 10:39 PM PDT     Moonset
Mon -- 10:59 PM PDT     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.70.80.80.60.2-0.2-0.6-0.7-0.5-0.3-00.20.50.60.60.3-0-0.5-0.9-1.1-0.9-0.7-0.40

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.