Thursday, October19, 2017 L-36.com


Marine Weather and Tides
Belvedere, 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 7:21AMSunset 6:26PM Thursday October 19, 2017 8:23 PM PDT (03:23 UTC) Moonrise 6:08AMMoonset 5:51PM Illumination 0% Phase: New Moon; Moon at 29 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- 216 Pm Pdt Thu Oct 19 2017
.small craft advisory in effect from 9 pm pdt this evening through late tonight...
Tonight..W winds 15 to 25 kt. Chance of rain in the evening, then chance of showers after midnight.
Fri..W winds 10 to 20 kt.
Fri night..W winds 10 to 20 kt.
Sat..W winds 5 to 15 kt.
Sat night..NW winds 5 to 15 kt.
Sun..W winds 5 to 15 kt.
Mon..N winds 5 kt.
Tue..N winds 10 kt.
PZZ500 216 Pm Pdt Thu Oct 19 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... A cold front will pass over the region later this evening, bringing the first rain of the wet season, a wind shift, and small craft criteria winds to the waters, with occasional gusts up to or exceeding 30 mph. A very robust northwest, long period, large swell train will arrive late this afternoon and through the evening, generating large waves and hazardous seas through at least Saturday. Operators of small crafts are urged to use extreme caution if out at sea over the next several days.

7 Day Forecast for Marine Location Near Belvedere, CA
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location: 37.83, -122.44     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 200055
afdmtr
area forecast discussion
national weather service san francisco bay area
555 pm pdt Thu oct 19 2017

Synopsis A cold front is still expected to move through the
area later today and tonight bringing widespread rainfall to the
region. The bulk of the rain will be in the north bay mountains
and coastal ranges. Along with precipitation, expect cooler
temperatures and breezy onshore winds through Friday. By late
Friday morning dry conditions will return lasting through the
forecast period. A warming trend is then on the way over the
weekend and into early next week. Temperatures are predicted to be
well above average during the beginning of next week.

Discussion As of 1:52 pm pdt Thursday... Current satellite
imagery showing parts of the bay area still under this morning's
stratus deck as the marine layer remains around 1500 ft. The
approaching cold front can also be seen on the satellite as it
nears the northern california coast. Rainfall is expected to reach
the sonoma and marin county coastal areas later this afternoon
before becoming more widespread late this evening and eventually
covering the remainder of the CWA by around midnight. Rainfall is
expected to be out of the san francisco bay area by tomorrow
morning's commute. Along with precipitation breezy southwesterly
winds will accompany the frontal passage.

Forecast rainfall totals have been updated to increase the amount
of precipitation for the north bay mountains. Latest model runs
indicate the north bay mountains could receive around 0.75" with
locally higher amounts possible in parts of sonoma county.

Otherwise, little changes have been made for the north bay
valleys. The santa cruz and santa lucia mountains are expected to
receive around 0.25" with less than two tenths of an inch
expected for most valley locations. Some areas in the southern and
far eastern portions of the CWA may see little to no rain. Cool
and breezy conditions are expected for the rest of the day Friday
after the precipitation has ended.

A warming trend is on tap for the weekend as an upper level ridge
starts to build over california. The ridge is expected to
strengthen as we head into the beginning of next week. 850 mb
temperatures are forecast to approach 25 degrees celsius through
mid week flirting with maximum climatological values for this
area. The ridge along with light offshore flow will result in warm
and dry conditions across the area Monday and Tuesday. Widespread
highs in the 80s and low to mid 90s are expected. Slight cooling
is possible on Wednesday for coastal areas, but warm conditions
will continue inland.

Aviation As of 5:15 pm pdt Thursday... For 00z tafs. CIGS are
beginning to lower as a cold front approaches from the northwest.

MVFR CIGS of 1000 ft are being reported in the north bay with
light rain and ifr vsbys of 2 sm. MVFR conditions are expected to
spread across the bay area with periods of light rain and wet
runways expected after 03z this evening as the front moves across
the area. Light to moderate southwesterly winds will continue
through this evening ahead of the front with winds anticipated to
veer to the west and become temporarily gusty around the time of
fropa. Gusts to 30 kt possible.

Overall forecast confidence: moderate
vicinity of ksfo... . MVFR CIGS currently being reported with
light rain and MVFR vsbys anticipated after 03z this evening.

Moderate southwesterly winds will veer to the west with fropa.

Gusty conditions are also expected with fropa. Wet runways
expected tonight with improving conditions expected by morning.

Llws also remains a possibility with FROPA (light at surface
gusting to 25-30mph at 2000ft agl).

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... MVFR CIGS will gradually to lower to ifr
around 700 ft around 04z-06z tonight. Light to moderate west to
southwesterly winds anticipated to continue through tonight. Light
rain will accompany fropa. Wet runways expected tonight with
improving conditions expected by morning.

Fire weather As of 5:55 pm pdt Thursday... Cooling occurred
today as onshore flow increased ahead of an approaching cold
front and widespread cloud cover began to overspread the area.

Relative humidity values increased significantly as well,
especially across the north bay hills. By late Thursday afternoon
light rain had begun to fall across the north bay. Expect light
rain to gradually spread south across the remainder of the
district Thursday night. Rainfall amounts will mostly be a quarter
of an inch or less, except locally more than a half inch in the
north bay mountains. Wetting rains are most likely across the
north bay and locally in the santa cruz mountains. Rainfall should
end in most areas by Friday morning. Friday will be a cool day
with brisk northwest winds.

A warming trend will get underway over the upcoming weekend as a
high pressure ridge begins to build over california. This ridge
will strengthen into early next week and result in warm and dry
conditions districtwide from Monday through Wednesday. Will need
to be wary of possible gusty offshore winds in the hills beginning
late in the weekend and continuing into Monday night.

Marine As of 05:00 pm pdt Thursday... A cold front will pass
over the region later this evening, bringing the first rain of
the wet season, a wind shift, and small craft criteria winds to
the waters, with occasional gusts up to or exceeding 30 mph. A
very robust northwest, long period, large swell train will arrive
late this afternoon and through the evening, generating large
waves and hazardous seas through at least Saturday. Operators of
small crafts are urged to use extreme caution if out at sea over
the next several days.

Mtr watches warnings advisories
Tngt High surf advisory... Coast from sonoma county south to
monterey county
sca... Mry bay from 9 pm
sca... Pt arena to pt reyes 0-10 nm from 9 pm
sca... Pt reyes to pigeon pt 0-10 nm from 9 pm
sca... Pigeon pt to pt pinos 0-10 nm from 9 pm
sca... Pt pinos to pt piedras blancas 0-10 nm from 9 pm
sca... Pigeon pt to pt piedras blancas 10-60 nm from 9 pm
sca... Pt arena to pigeon pt 10-60 nm
sca... Rough bar advisory for sf bar from 9 pm
sca... Sf bay from 9 pm until 3 am
public forecast: as
aviation: cw
marine: drp
fire weather: dykema
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
FTPC1 - 9414290 - San Francisco, CA 2 mi54 min SSW 8 G 16 60°F 58°F1012.2 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 3 mi84 min SSE 2.9 G 6 61°F 1011.1 hPa
PXSC1 3 mi54 min 62°F
TIBC1 - Tiburon Pier, San Francisco Bay, CA 4 mi67 min SE 4.1 58°F 1012 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 6 mi54 min S 9.9 G 14
OBXC1 6 mi54 min 62°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 6 mi54 min S 11 G 14 61°F 1011.9 hPa
RCMC1 - 9414863 - Richmond, CA 7 mi54 min S 8.9 G 12 59°F 60°F1011.7 hPa
AAMC1 - 9414750 - Alameda, CA 8 mi54 min S 9.9 G 14 61°F 63°F1012.7 hPa
LNDC1 9 mi54 min SSW 11 G 14 61°F 1012.2 hPa
46237 - San Francisco Bar, CA (142) 11 mi84 min 55°F5 ft
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 18 mi84 min WSW 12 G 14 60°F 1011.5 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 22 mi54 min S 7 G 8.9 61°F 63°F1012 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 22 mi94 min S 14 G 16 56°F 55°F4 ft1012.3 hPa (-1.4)
RTYC1 - 9414523 - Redwood City, CA 25 mi54 min S 5.1 G 8.9 62°F 65°F1012.3 hPa
PCOC1 - 9415144 - Port Chicago, CA 26 mi54 min SSW 8 G 13 61°F 63°F1011.8 hPa
PRYC1 - 9415020 - Point Reyes, CA 31 mi54 min N 4.1 G 8.9 55°F1011.1 hPa
SFXC1 - San Francisco Bay Reserve, CA 34 mi99 min W 8.9 60°F 1011 hPa55°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 40 mi94 min S 12 G 14 59°F 58°F5 ft1012.2 hPa (-1.5)

Wind History for San Francisco, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
San Francisco, San Francisco International Airport, CA15 mi28 minS 1110.00 miOvercast62°F57°F84%1012.1 hPa
Oakland, Metro Oakland International Airport, CA15 mi31 minSSW 1310.00 miMostly Cloudy61°F57°F90%1012.3 hPa
Hayward, Hayward Air Terminal, CA21 mi30 minS 89.00 miLight Rain63°F54°F73%1013.4 hPa
Half Moon Bay Airport, CA22 mi29 minSSE 99.00 miOvercast57°F55°F94%1011.8 hPa
Novato / Gnoss Field, CA23 mi29 minSW 910.00 miOvercast59°F57°F94%1011.8 hPa
San Carlos Airport, CA23 mi37 minSE 1010.00 miMostly Cloudy61°F57°F88%1012.9 hPa
Concord, Buchanan Field, CA23 mi31 minS 96.00 miLight Rain Fog/Mist62°F57°F86%1010.3 hPa

Wind History from SFO (wind in knots)
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Last 24hrW12W6W10W11
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W7W5SW5W8W7W6W3W5W3SW4SW4SW5NW6SW11W13
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1 day agoNW12W11W13W12W11NW14NW12W6W6W7W7W4CalmS5CalmE3E4N5NW14W19W21W17W17W15
2 days agoW5CalmCalmCalmCalmCalmCalmW5CalmCalmCalmS3CalmN3CalmE4N3NE4NW8NW8NW13NW14NW15NW12

Tide / Current Tables for Alcatraz Island, San Francisco Bay, California
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Alcatraz Island
Click for Map
Thu -- 12:10 AM PDT     5.35 feet High Tide
Thu -- 05:46 AM PDT     1.14 feet Low Tide
Thu -- 07:08 AM PDT     Moonrise
Thu -- 07:22 AM PDT     Sunrise
Thu -- 12:12 PM PDT     New Moon
Thu -- 12:14 PM PDT     5.97 feet High Tide
Thu -- 06:23 PM PDT     0.23 feet Low Tide
Thu -- 06:26 PM PDT     Sunset
Thu -- 06:50 PM PDT     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
5.35.14.33.22.11.31.21.62.43.54.65.55.95.84.93.52.10.90.30.3123.14.1

Tide / Current Tables for Alcatraz Island W, San Francisco Bay, California Current
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Alcatraz Island W
Click for Map
Thu -- 01:32 AM PDT     -0.00 knots Slack
Thu -- 04:10 AM PDT     -2.09 knots Max Ebb
Thu -- 07:08 AM PDT     Moonrise
Thu -- 07:22 AM PDT     Sunrise
Thu -- 07:25 AM PDT     0.00 knots Slack
Thu -- 10:23 AM PDT     2.71 knots Max Flood
Thu -- 12:12 PM PDT     New Moon
Thu -- 01:34 PM PDT     -0.01 knots Slack
Thu -- 04:27 PM PDT     -2.56 knots Max Ebb
Thu -- 06:26 PM PDT     Sunset
Thu -- 06:50 PM PDT     Moonset
Thu -- 07:54 PM PDT     0.00 knots Slack
Thu -- 10:58 PM PDT     2.97 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.10.9-0.6-1.7-2.1-1.9-1.4-0.50.82.12.72.620.9-0.6-1.8-2.5-2.5-2-1.10.11.72.73

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 (23,6,7,8)
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Ground Weather Radar Station San Francisco Bay Area, 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.