Tuesday, January16, 2018 L-36.com


Marine Weather and Tides
Muir Beach, 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 5:18PM Tuesday January 16, 2018 5:20 AM PST (13:20 UTC) Moonrise 7:03AMMoonset 5:14PM 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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PZZ545 Point Reyes To Pigeon Point To 10 Nm- 240 Am Pst Tue Jan 16 2018
.small craft advisory for rough bar in effect through this evening...
Today..NW winds 10 kt. Wind waves 2 ft or less. W swell 12 to 14 ft at 16 seconds. Slight chance of rain in the morning.
Tonight..N winds 10 kt. Wind waves 2 ft or less. W swell 11 to 13 ft at 15 seconds.
Wed..SE winds 10 kt...becoming sw in the afternoon. Wind waves 3 to 4 ft. W swell 9 to 12 ft at 15 seconds.
Wed night..SW winds 5 to 15 kt. Wind waves 1 to 3 ft. W swell 8 to 9 ft at 21 seconds. Slight chance of rain.
Thu..S winds 10 to 20 kt...becoming w. Wind waves 3 to 5 ft. W swell 16 to 19 ft at 21 seconds. Rain likely in the morning, then chance of rain in the afternoon. Chance of showers.
Fri..NW winds 10 to 20 kt. Wind waves 2 to 4 ft. W swell 13 to 16 ft. Chance of showers, then slight chance of showers.
Sat..NW winds 15 to 25 kt. Wind waves 3 to 5 ft. W swell 11 to 14 ft. Slight chance of rain.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 10 to 13 ft at 17 seconds. Across the bar...combined seas 12 to 15 ft at 17 seconds. Maximum ebb current of 1.4 knots at 04:01 am Tuesday and 2.8 knots at 03:43 pm Tuesday.
PZZ500 240 Am Pst Tue Jan 16 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Weak high pressure off the california coast will keep light northwest winds for today. Winds will switch southerly late tonight and Wednesday as a low pressure system deveops off the british columbia coast and pushes the high south. Large swells will impact the beaches through early tonight before decreasing. A larger swell with long period will arrive Thursday.

7 Day Forecast for Marine Location Near Muir Beach, CA
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location: 37.78, -122.67     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 161159
afdmtr
area forecast discussion
national weather service san francisco bay area
359 am pst Tue jan 16 2018

Synopsis A few lingering showers this morning otherwise dry but
continued cloudy today. Dry and continued mostly cloudy Wednesday
as moist flow comes in off the pacific. Next front moves in
Thursday with rain spreading north to south across the district
reaching the central coast by Thursday night. Precip will turn
showery later Thursday night into Friday as the cold upper trough
passes over the region with one of the colder airmass so far this
season. Dry but cool on Saturday before clouds increase again on
Sunday as the next front arrives with rain later Sunday into
Monday.

Discussion As of 3:38 am pst Tuesday... Radar still picking up
returns over bay area but most activity will be east of the area
by rush hour sunrise. Coastal sonoma county had a few sites report
upwards of half an inch at sea ranch on the coast and the oak
ridge raws located in the wet coastal hills. Most other locations
are reporting only a few hundredths with little or no rain south
of about the dumbarton bridge. So by the time most people start
the day any precip will have ended. However a moist zonal flow is
set up across the pacific and clouds will continue to stream
across the region today keeping daytime highs stuck around 60.

No changes of note for weds with a forecast of partly mostly
cloudy skies but continued dry and seasonably mild with highs
upper 50s to upper 60s.

The next front of interest is due to arrive later Thursday. The
models have been remarkably consistent with the timing and
intensity of this system, even beyond 240 hour forecasts! High
confidence that a well organized frontal boundary will move into
the north bay Thursday morning and then charge southward through
the bay area and reach the central coast by Thursday evening. The
fast moving nature of the system will limit rainfall potential
with current QPF forecasts showing 0.25-0.75 on average. So this
looks like a typical moderate winter-time storm. Winds will
briefly gust to around 35 mph during frontal passage as rain
drags down higher momentum air. The fast nature of the frontal
passage and modest rain totals should preclude any significant
hydro issues outside of typical commute impacts and blocked storm
drains. As always will need to monitor for brief heavy rain-rates
over the north bay burn scars, as its often the short duration
bursts versus long term heavy rain that can cause debris flows.

Precip will turn showery later Thursday night into Friday morning
as 1000-500 mb thickness values plummet to around 528 dm with 850
mb temps to around -2 celsius suggesting we should see snow on the
higher peaks of the bay area. On Friday there will be numerous
post-frontal showers, especially for the coastal hills that
benefit from cold northwest wind flow. 700 mb temps as cold as -13
celsius with sea surface temps in the upper 50s will allow for big
delta t in the lower levels. This type of pattern can produce
locally heavy rain for the monterey coast and big sur hills where
the forecast will show accumulating snow above 3500 feet for any
hikers in the los padres forest. Daytime highs on Friday will
struggle to reach 55 for nearly all areas with periodic cold rain
showers dragging down cold air. Although not in the forecast at
this time, small hail and graupel will certainly be possible as
well.

After a cold start Saturday morning, the forecast to start the
weekend looks dry but continued cool.

Will be watching for the next system to arrive later Sunday into
Monday with another round of soaking rain forecast for the
district. Latest model trends suggest front will be fairly fast
moving and pass through sometime Sunday night. Earlier solutions
showed the boundary stalling but not seeing those signals at this
time. These systems have fairly cold air associated with them and
are progressive so hydro issues should be minimal with beneficial
rainfall the main impact.

Aviation As of 4:00 am pst Tuesday... MVFR CIGS fairly
widespread across the north bay and the sfo bay area this morning
as a weak front moves through. Light rain has been reported at
times. Models indicate drier air in the midlevels working its way
down to the surface later this morning. ExpectingVFR conditions
for the north bay and sfo bay area after 18z. Lvk is a tricky
forecast due to the influence of clouds from the central valley
which could keep CIGS through the day.

Vicinity of ksfo... MVFR CIGS through 18z with some light rain
through 15z.

Sfo bridge approach... Same as ksfo.

Monterey bay terminals... Some fog around sns will bring vsbys down
to 1 2 mile at times through 16z. Otherwise MVFR CIGS through 17z.

Marine As of 02:41 am pst Tuesday... Weak high pressure off the
california coast will keep light northwest winds for today. Winds
will switch southerly late tonight and Wednesday as a low
pressure system develops off the british columbia coast and
pushes the high south. Large swells will impact the beaches
through early tonight before decreasing. A larger swell with long
period will arrive Thursday.

Mtr watches warnings advisories
Tday High surf advisory... Sonoma county coast to monterey county coast
sca... Rough bar advisory for sf bar
public forecast: rww
aviation: W pi
marine: W pi
visit us at

Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
46237 - San Francisco Bar, CA (142) 2 mi81 min 54°F11 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 9 mi91 min SSE 9.7 G 12 54°F 54°F11 ft1020.9 hPa (-0.0)
TIBC1 - Tiburon Pier, San Francisco Bay, CA 14 mi57 min NW 1.9 53°F 1022 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 15 mi51 min SSE 4.1 G 5.1 56°F 1020.5 hPa
PXSC1 15 mi51 min 57°F 55°F
RCMC1 - 9414863 - Richmond, CA 17 mi51 min NNW 2.9 G 2.9 54°F 53°F1021.6 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 18 mi51 min Calm G 1
OBXC1 18 mi51 min 54°F 54°F
PPXC1 - 9414847 - Richmond (Point Potrero), CA 18 mi51 min N 4.1 G 5.1 56°F 1022 hPa
OKXC1 - 9414776 - Oakland (Berth 34), CA 18 mi51 min Calm G 1.9 54°F 1021.7 hPa
AAMC1 - 9414750 - Alameda, CA 20 mi51 min E 1 G 1.9 55°F 54°F1021.6 hPa
LNDC1 21 mi51 min Calm G 1 56°F 1021.5 hPa
PRYC1 - 9415020 - Point Reyes, CA 22 mi51 min ESE 1 G 4.1 54°F1021.3 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 29 mi51 min E 9.9 G 11 52°F 1021.7 hPa
RTYC1 - 9414523 - Redwood City, CA 31 mi51 min SE 1.9 G 2.9 55°F 55°F1022 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 31 mi91 min SSE 9.7 G 12 56°F 57°F15 ft1020.8 hPa (+0.5)
MZXC1 - 9415102 - Martinez-Amorco CA 34 mi51 min NE 5.1 G 7 50°F 52°F1022.6 hPa50°F
PCOC1 - 9415144 - Port Chicago, CA 38 mi51 min ENE 13 G 15 50°F 51°F1022.3 hPa
46214 - Point Reyes, CA (029) 44 mi51 min 56°F11 ft
SFXC1 - San Francisco Bay Reserve, CA 45 mi96 min ENE 2.9 49°F 1022 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 45 mi57 min E 5.1 G 6 50°F 1022.7 hPa
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 46 mi41 min ENE 3.9 G 7.8 56°F 56°F1021.5 hPa56°F

Wind History for San Francisco, CA
(wind in knots)    EDIT      (on/off)   Help
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
San Francisco, San Francisco International Airport, CA20 mi25 minN 08.00 miOvercast56°F52°F87%1022 hPa
Half Moon Bay Airport, CA21 mi26 minN 00.75 miFog/Mist55°F55°F100%1021.3 hPa
Oakland, Metro Oakland International Airport, CA24 mi28 minN 09.00 miOvercast55°F52°F90%1022.2 hPa

Wind History from SFO (wind in knots)
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Last 24hrW3NE8N9S5CalmN5NE8NE4N5NE3NW5E5N3N3E4SE3E4NE4SE3E4CalmSE6SW3E3
1 day agoS5E9E8SE5E5E5E5SE5E3E3CalmNE4NE6NE4NE7SE3SE8SW4N5CalmCalmS3SE3SW3
2 days agoCalmS5SE5SE5NE3E6E8SE9E7E7E5E5E4E7NE11E9E7NE6NE12E10E11E12E5E5

Tide / Current Tables for San Francisco Bar, California
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San Francisco Bar
Click for Map
Tue -- 04:05 AM PST     2.93 feet Low Tide
Tue -- 07:02 AM PST     Moonrise
Tue -- 07:24 AM PST     Sunrise
Tue -- 09:58 AM PST     5.94 feet High Tide
Tue -- 04:50 PM PST     -0.42 feet Low Tide
Tue -- 05:14 PM PST     Moonset
Tue -- 05:16 PM PST     Sunset
Tue -- 06:18 PM PST     New Moon
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
4.54.23.63.12.93.13.64.35.15.75.95.64.73.41.90.6-0.2-0.4-0.10.71.62.73.74.4

Tide / Current Tables for South Channel, San Francisco Bay Approach, California Current
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South Channel
Click for Map
Tue -- 12:20 AM PST     -0.00 knots Slack
Tue -- 02:24 AM PST     -0.80 knots Max Ebb
Tue -- 05:20 AM PST     0.00 knots Slack
Tue -- 07:01 AM PST     Moonrise
Tue -- 07:23 AM PST     Sunrise
Tue -- 08:09 AM PST     1.00 knots Max Flood
Tue -- 11:20 AM PST     -0.00 knots Slack
Tue -- 02:29 PM PST     -1.83 knots Max Ebb
Tue -- 05:13 PM PST     Moonset
Tue -- 05:16 PM PST     Sunset
Tue -- 06:14 PM PST     0.01 knots Slack
Tue -- 06:18 PM PST     New Moon
Tue -- 09:18 PM PST     1.38 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.2-0.4-0.8-0.8-0.5-0.20.30.810.90.60.2-0.5-1.3-1.8-1.8-1.4-0.9-0.20.61.11.41.31.1

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 (8,2,3,4)
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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.