Thursday, January18, 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 7:20AMSunset 5:20PM Thursday January 18, 2018 5:22 AM PST (13:22 UTC) Moonrise 8:24AMMoonset 7:03PM Illumination 3% Phase: Waxing Crescent; Moon at 2 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- 222 Am Pst Thu Jan 18 2018
.small craft advisory for rough bar in effect through Friday afternoon...
.small craft advisory for hazardous seas in effect through Friday afternoon...
Today..S winds 5 to 15 kt...becoming W in the afternoon. Wind waves 3 to 4 ft. W swell 15 to 18 ft at 19 seconds. Rain likely in the morning, then chance of rain in the afternoon.
Tonight..SW winds 10 to 20 kt...becoming nw 5 to 15 kt after midnight. Wind waves 3 to 5 ft. W swell 15 to 18 ft at 16 seconds. Chance of rain in the evening, then chance of showers after midnight.
Fri..NW winds 5 to 15 kt. Wind waves 1 to 3 ft. W swell 13 to 16 ft at 15 seconds. Chance of showers and slight chance of Thunderstorms.
Fri night..NW winds 10 to 20 kt. Wind waves 2 to 4 ft. W swell 11 to 14 ft at 14 seconds. Slight chance of showers.
Sat..NW winds 15 to 25 kt. Wind waves 3 to 5 ft. W swell 10 to 13 ft at 14 seconds. Slight chance of showers in the morning.
Sun..SE winds 15 to 25 kt. Wind waves 3 to 5 ft. W swell 7 to 9 ft. Chance of rain.
Mon..NW winds 5 to 15 kt. Wind waves 1 to 3 ft. W swell 9 to 12 ft. Chance of showers.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 8 to 10 ft at 14 seconds...increasing to 12 to 15 ft at 20 seconds later this morning. Across the bar...combined seas 8 to 10 ft at 14 seconds... Increasing to 14 to 17 ft at 20 seconds later this morning. Maximum ebb current of 1.5 knots at 05:31 am Thursday and 2.9 knots at 05:01 pm Thursday.
PZZ500 222 Am Pst Thu Jan 18 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... A large long period westerly swell will continue to impact the coastal waters through the remainder of the week. This swell will bring hazardous seas to the region as well as large breaking waves to the coastline through Friday. A cold front will pass over the waters later this morning, switching winds out of the west or northwest by this afternoon or evening. Rain chances will increase through the morning and will continue through the weekend.

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 181205
afdmtr
area forecast discussion
national weather service san francisco bay area
405 am pst Thu jan 18 2018

Synopsis A weather system approaching form the northwest will
spread rain across the north bay this morning and then southward
across the remainder of the forecast area by this evening.

Scattered showers are forecast for Thursday night and Friday as
much colder air settles over the region. A few showers may linger
into early Saturday morning, but for the most part Saturday
should be a dry day. The next front will bring rain chances late
Sunday into Monday.

Discussion As of 3:15 am pst Thursday... Latest satellite
imagery shows a cold frontal boundary approaching the northern
california coast this morning. Models forecast light rain to begin
spreading into the north bay this morning then reach the northern
san francisco bay area by late morning then across the rest of
the sf bay area by mid-afternoon and then into the monterey bay
area by late afternoon. Rain will turn to scattered showers
Thursday night and Friday after the front passes. The best chance
for showers will be Friday morning when the upper trough is moving
southeast across the coastal waters towards southern california.

The flow will be northwest by then so shower chances are a little
higher along the coast.

Colder air will settle into the area with 850 mb temps dropping
from about 12 degrees c currently to -2 degrees c by Friday
morning. Cold air instability will bring a slight chance of
thunderstorms along the north bay coast and the coastal waters
where the trough will be passing through. Snow level will drop as
low as 3500 feet by Friday but by then there will only be scattered
light showers so only a dusting of snow is expected. Rainfall
amounts from this system will range from 1 2 inch in the north
bay... 1 4 inch around the san francisco bay area... And 1 10 inch
from monterey bay area south. Up to 3 4 inch is possible in the
coastal hills.

Lingering showers Friday night should remain over the waters.

Clearing skies will lead to a cold night with lows dropping to
the mid to upper 30s in the inland valleys.

Another system from the northwest will bring a chance of rain to
the north bay Sunday afternoon and the san francisco bay area
Sunday night. The front washes out as it moves southeast with rain
only getting as far as the monterey bay area Monday morning.

Rainfall amounts could be locally moderate in the north bay but
light elsewhere. The system is fast-moving so hydro issues are
not expected.

Medium range models show another fast-moving system moving through
around the middle of next week. But after that an upper level
ridge will build off the coast leading to an extended dry period.

Aviation As of 3:54 am pst Thursday... For 12z tafs... Widespread
ifr lifr CIGS & vsbys across the district this morning as an
upper level trough and cold front approach from the northwest. The
trough will introduce some rain and showers this morning. In
fact, ksts is already reporting -ra as of 1130z. Expect rain to
move north to south through the morning, becoming widespread by
this afternoon. Showers will linger this evening and into Friday.

S SW winds will turn westerly this afternoon.

Vicinity of ksfo... Lifr to vlifr conditions will prevail through
at least 15z, perhaps later, with vsbys down to 1 2sm-2sm and
fog at times. Wet runways by late morning or early afternoon,
with low confidence on exact timing. Light winds.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... Lifr vlifr expected through the morning.

Ksns still reporting clr skies. Will have to see if low clouds
make it through the salinas valley later on this morning. Rain
will begin around 22z-00z Thursday afternoon. Light winds.

Marine As of 02:35 am pst Thursday... A large long period
westerly swell will continue to impact the coastal waters through
the remainder of the week. This swell will bring hazardous seas to
the region as well as large breaking waves to the coastline
through Friday. A cold front will pass over the waters later this
morning, switching winds out of the west or northwest by this
afternoon or evening. Rain chances will increase through the
morning and will continue through the weekend.

Mtr watches warnings advisories
Tday High surf warning... Sonoma county coast to monterey
county coast
sca... Mry bay
sca... Pt reyes to pigeon pt 0-10 nm
sca... Pigeon pt to pt pinos 0-10 nm
sca... Pt pinos to pt piedras blancas 0-10 nm
sca... Pigeon pt to pt piedras blancas 10-60 nm
sca... Pt arena to pt reyes 0-10 nm
sca... Pt arena to pigeon pt 10-60 nm
sca... Rough bar advisory for sf bar
public forecast: W pi
aviation: bam
marine: bam
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 mi53 min 54°F9 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 9 mi93 min SE 7.8 G 12 52°F 55°F8 ft1019.5 hPa (-2.1)
FTPC1 - 9414290 - San Francisco, CA 11 mi53 min E 1.9 G 7 53°F 54°F1019.8 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 15 mi53 min SSE 8.9 G 12 53°F 1018.4 hPa
PXSC1 15 mi53 min 54°F 54°F
RCMC1 - 9414863 - Richmond, CA 17 mi53 min SSW 2.9 G 4.1 52°F 54°F1019.5 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 18 mi53 min S 6 G 8.9
OKXC1 - 9414776 - Oakland (Berth 34), CA 18 mi53 min S 6 G 8.9 53°F 1019.7 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 18 mi53 min S 6 G 7 54°F 1019.8 hPa
OBXC1 18 mi53 min 53°F 53°F
AAMC1 - 9414750 - Alameda, CA 20 mi53 min SSE 6 G 8.9 53°F 55°F1019.7 hPa
LNDC1 21 mi53 min S 7 G 8 53°F 1019.5 hPa
PRYC1 - 9415020 - Point Reyes, CA 22 mi53 min ESE 4.1 G 7 54°F1018.9 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 29 mi53 min Calm G 1 51°F 1019.4 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 31 mi93 min SE 7.8 G 12 54°F 57°F10 ft1019.3 hPa (-1.9)
RTYC1 - 9414523 - Redwood City, CA 31 mi53 min SSE 4.1 G 5.1 51°F 56°F1020.5 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 34 mi53 min ESE 1.9 G 5.1 51°F 52°F1019.8 hPa51°F
PCOC1 - 9415144 - Port Chicago, CA 38 mi53 min ESE 1 G 1.9 50°F 52°F1019.7 hPa
46214 - Point Reyes, CA (029) 44 mi53 min 57°F14 ft
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 45 mi53 min SSE 9.9 G 13 51°F 1019.5 hPa
SFXC1 - San Francisco Bay Reserve, CA 45 mi98 min SSE 2.9 51°F 1020 hPa
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 46 mi43 min SE 12 G 18 55°F 56°F1019.1 hPa55°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 mi27 minSE 70.50 miFog51°F48°F92%1019.5 hPa
Half Moon Bay Airport, CA21 mi28 minN 04.00 miFog/Mist48°F46°F94%1018.6 hPa
Oakland, Metro Oakland International Airport, CA24 mi30 minSSE 104.00 miFog/Mist52°F52°F100%1019.8 hPa

Wind History from SFO (wind in knots)
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Last 24hrCalmE3SE5E4CalmCalmCalmNE4E6N4E4NE4N7N6N6S3N5NE5CalmCalmSW4N4SE5S3
1 day agoCalmCalmCalmNE4NE5N5N5NE5N7N10N7N4N5NE9N5NE5CalmNE5NE3CalmN3N6N4N3
2 days agoW3NE8N9S5CalmN5NE8NE4N5NE3NW5E5N3N3E4SE3E4NE4SE3E4CalmSE6SW3E3

Tide / Current Tables for San Francisco Bar, California
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San Francisco Bar
Click for Map
Thu -- 12:32 AM PST     4.67 feet High Tide
Thu -- 05:17 AM PST     2.90 feet Low Tide
Thu -- 07:23 AM PST     Sunrise
Thu -- 08:24 AM PST     Moonrise
Thu -- 11:09 AM PST     5.75 feet High Tide
Thu -- 05:18 PM PST     Sunset
Thu -- 05:54 PM PST     -0.34 feet Low Tide
Thu -- 07:03 PM PST     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
4.64.64.33.73.22.933.44.14.85.45.75.64.83.52.10.8-0.1-0.3-00.71.72.83.8

Tide / Current Tables for South Channel, San Francisco Bay Approach, California Current
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South Channel
Click for Map
Thu -- 01:36 AM PST     -0.01 knots Slack
Thu -- 03:39 AM PST     -0.88 knots Max Ebb
Thu -- 06:33 AM PST     0.00 knots Slack
Thu -- 07:23 AM PST     Sunrise
Thu -- 08:23 AM PST     Moonrise
Thu -- 09:25 AM PST     0.96 knots Max Flood
Thu -- 12:34 PM PST     -0.01 knots Slack
Thu -- 03:47 PM PST     -1.80 knots Max Ebb
Thu -- 05:18 PM PST     Sunset
Thu -- 07:03 PM PST     Moonset
Thu -- 07:23 PM PST     0.00 knots Slack
Thu -- 10:23 PM PST     1.34 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.90.4-0.3-0.8-0.9-0.6-0.20.20.60.90.90.70.3-0.3-1-1.6-1.8-1.5-0.9-0.30.411.31.3

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.