Thursday, January17, 2019 L-36.com


Marine Weather and Tides
Lagunitas-Forest Knolls, CA

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 7:22AMSunset 5:17PM Thursday January 17, 2019 8:45 AM PST (16:45 UTC) Moonrise 2:08PMMoonset 3:40AM Illumination 88% Phase: Waxing Gibbous; Moon at 11 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 Coastal Waters From Point Reyes To Pigeon Point California Out To 10 Nm- 251 Am Pst Thu Jan 17 2019
.small craft advisory in effect through Friday afternoon...
Today..SW winds 10 to 20 kt with gusts up to 25 kt...becoming 10 to 15 kt this afternoon. Wind waves 3 to 4 ft this morning... Becoming 2 ft or less. W swell 17 to 22 ft at 20 seconds. Showers and a slight chance of Thunderstorms.
Tonight..SW winds 5 to 15 kt. Wind waves 2 ft or less. W swell 17 to 22 ft at 18 seconds.
Fri..S winds 5 to 15 kt. Wind waves 2 ft or less. W swell 11 to 16 ft at 15 seconds. A slight chance of showers.
Fri night..S winds 5 to 15 kt. Wind waves 2 ft or less. W swell 8 to 11 ft at 14 seconds. A slight chance of showers.
Sat..S winds 5 to 10 kt. Wind waves 2 ft or less. W swell 6 to 8 ft at 13 seconds. A slight chance of showers.
Sat night..S winds 5 to 10 kt. Wind waves 2 ft or less. W swell 7 to 9 ft at 13 seconds. A chance of showers.
Sun..W winds 10 to 15 kt. Wind waves 2 ft or less. W swell 6 to 8 ft.
Martin luther king jr day..NW winds 10 to 20 kt. Wind waves 2 ft or less. W swell 5 to 8 ft. Winds and wind waves higher in and near Thunderstorms.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 10 to 13 at 14 seconds, increasing to 15 to 20 ft around Sunrise at 20 seconds. Across the bar...combined seas 12 to 15 at 14 seconds, increasing to 17 to 22 ft around Sunrise at 20 seconds. Maximum ebb current of 3.2 knots at 12:49 pm Thursday and 1.4 knots at 01:43 am Friday.
PZZ500 251 Am Pst Thu Jan 17 2019
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Southerly winds are forecast to gradually diminish through the morning. Meanwhile, a very large and long period west swell will arrive this morning, build through the day and persist into Friday. This incoming swell will prolong the hazardous sea conditions throughout the waters, particularly for small vessels.


7 Day Forecast for Marine Location Near Lagunitas-Forest Knolls CDP, CA
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location: 37.98, -122.74     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 171218
afdmtr
area forecast discussion
national weather service san francisco bay area
418 am pst Thu jan 17 2019

Synopsis Cold front has pushed through the area with scattered
showers developing in the postfrontal unstable airmass. Showers
and isolated thunderstorms will continue on Thursday. A chance of
showers will persist Friday and Saturday across the north bay with
dry conditions elsewhere. A chance of light rain will return
regionwide on Sunday as a weak front passes through. Dry weather
returns Monday through the rest of next week with mild
temperatures.

Discussion As of 3:45 am pst Thursday... Strong cold front and
atmospheric river have pushed southeast, ending the threat of
heavy rain. A few showers have lingered, mainly across the north
bay and in the higher coastal terrain. Winds have also decreased
behind the front with gusts up to 40 mph in the higher elevations
and most lower elevations below 20 mph. Scattered showers are
developing in the cool unstable airmass with some embedded
thunderstorms. So far thunderstorms have stayed to our north in
mendocino county but these may develop further south into the
morning hours. A slight chance of thunderstorms is in the forecast
through Thursday afternoon. Low freezing levels will support
small hail reaching the ground in thunderstorms which form. Brief
heavy rain is also possible with any storms. Outside of any
thunderstorms which form additional rainfall amounts are expected
to be light, with up to an inch in the north bay and coastal
mountains, less than a half inch in the north bay valleys, and
less than a quarter inch elsewhere. Locally higher amounts are
possible where any thunderstorms form.

Small streams have crested with streams in the north
bay above flood stage gradually dropping. The napa and russian
rivers are continuing to rise but are expected to crest early
Thursday and remain below flood stage. A few rivers across the
southern portion of the area continue to be on the rise with a
few rising into minor flood stage. With the heavy rain ended these
should peak early Thursday as well.

An upper level ridge will then build over the area on Friday. This
will push the storm track to our north, keeping most of the area
dry. While the vast majority of the precipitation will fall to our
north, some moisture will make it far enough south to bring a
chance of showers into the north bay Friday and Saturday. Rainfall
amounts will be very light with less than a quarter inch fri-sat.

High temperatures during this time will be warmest across the
southern areas, warming into the mid 60s from san jose south on
Saturday. Low temperatures will cool somewhat versus the past
couple of nights, but moisture and a mild airmass will keep lows
in the mid 40s to low 50s.

A shortwave trough will swing through the area on Sunday,
bringing a better chance of rain to the area. This system appears
to be rather weak with the surface low remaining well to our north
and only a weak surface pressure gradient setting up over the
area. Rainfall amounts are expected to be light with cold air
advection setting up by late Sunday morning, limiting
precipitation production. Cooler air will move in behind the
trough, which will drop high temperatures back into the upper 50s
to around 60.

From mlk day onward, a high amplitude pattern will develop with
strong ridging along the west coast and a deep trough in the
center of the continent. This will keep the area dry for several
days, with temperatures gradually warming under the ridge, with
highs in the low to mid 60s likely by mid week. Models are in good
agreement about the ridge becoming anchored to the coast through
at least the end of next week.

Aviation As of 04:15 am pst Thursday... For 12z tafs. Southwest
winds have diminished greatly in wake of the frontal passage
overnight. However, continue to see locally gusty conditions
around the san francisco bay terminals and near those near the
coast. While a few lingering showers persist, steady rain has
ended with mainly MVFR conditions prevailing. Look for locally
gusty winds to continue through this afternoon with the potential
for passing showers to briefly impacting regional terminals.

Vicinity of ksfo... MVFR conditions with southwest winds gusting to
around 25 knots. Look for gusty conditions to persist through the
afternoon before diminishing late tonight into Friday morning.

Sfo bridge approach... Similar to sfo.

Monterey bay terminals... MVFR conditions prevail with occasionally
gusty southwest winds to around 20 knots.

Beaches As of 04:15 am pst Thursday... A large and long period
westerly swell will enter the coastal waters this morning and
build through the day. Westerly swells of 19 to 27 feet with a
period of 17 to 21 seconds will peak this afternoon and result in
breaking waves of 25 to 35 feet, favored locations up to or
exceeding 45 feet. Thus, a high surf warning remains in effect
through Friday. These large breaking waves will lead to increased
wave run- up on beaches with waves topping and washing over large
rocks and jetties. These conditions may also produce localized
coastal flooding of vulnerable locations, especially early this
morning during high tide. Use extreme caution near the surf zone
as these large waves will be capable of sweeping people into the
frigid and turbulent ocean water. Cold water shock may cause
cardiac arrest, and it also can cause an involuntary gasp reflex
causing drowning, even for a good swimmer. The surf zone will be
very dangerous due to strong currents and powerful breaking waves.

The large swell is forecast to gradually subside on Friday.

Marine As of 04:15 am pst Thursday... Southerly winds are
forecast to gradually diminish through the morning. Meanwhile, a
very large and long period west swell will arrive this morning,
build through the day and persist into Friday. This incoming swell
will prolong the hazardous sea conditions throughout the waters,
particularly for small vessels.

Mtr watches warnings advisories
Tday Coastal flood advisory... Caz006-505-506-508>510-529-530
high surf warning... Caz006-505-509-529-530
sca... Mry bay
sca... Pt arena to pt reyes 0-10 nm
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... Pt arena to pigeon pt 10-60 nm
sca... Pigeon pt to pt piedras blancas 10-60 nm
sca... Sf bay until 9 am
public forecast: st
aviation: rgass
marine: rgass
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
PRYC1 - 9415020 - Point Reyes, CA 13 mi33 min 54°F1013.5 hPa
46237 - San Francisco Bar, CA (142) 15 mi45 min 56°F11 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 16 mi25 min SW 14 G 19 55°F 56°F1014.6 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 17 mi46 min NE 2.9 52°F 1014 hPa
RCMC1 - 9414863 - Richmond, CA 18 mi27 min 53°F
FTPC1 - 9414290 - San Francisco, CA 19 mi33 min SW 5.1 G 8.9 53°F 55°F1014.5 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 21 mi27 min SSW 8 G 11 54°F 1014.4 hPa
PXSC1 22 mi33 min 54°F 54°F
PXOC1 - 9414311 - San Francisco (Pier 1), CA 22 mi33 min SW 7 G 12 53°F 1013.2 hPa
OBXC1 24 mi27 min 53°F 53°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 25 mi33 min SW 13 G 16
OKXC1 - 9414776 - Oakland (Berth 34), CA 25 mi33 min SW 8 G 12 53°F 1014.3 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 26 mi27 min SSW 8 G 11 53°F 1013.8 hPa
LNDC1 27 mi33 min WSW 11 G 15 53°F 1014.3 hPa
AAMC1 - 9414750 - Alameda, CA 27 mi33 min W 8.9 G 14 53°F 53°F1014.7 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 33 mi33 min SW 12 G 17 52°F 52°F1014.3 hPa52°F
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 35 mi25 min SW 18 G 23 55°F1013.2 hPa
PCOC1 - 9415144 - Port Chicago, CA 38 mi33 min SW 8.9 G 15 52°F 51°F1014.3 hPa
46214 - Point Reyes, CA (029) 39 mi45 min 56°F24 ft
SFXC1 - San Francisco Bay Reserve, CA 41 mi60 min WSW 8.9 52°F 1014 hPa49°F
RTYC1 - 9414523 - Redwood City, CA 43 mi33 min SSE 5.1 G 8 56°F 53°F1015.3 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 45 mi27 min WNW 9.9 G 13 52°F 1014.5 hPa

Wind History for Point Reyes, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Novato / Gnoss Field, CA15 mi50 minWSW 13 G 187.00 miMostly Cloudy55°F48°F77%1013.5 hPa
Petaluma Municipal Airport, CA20 mi50 minSW 76.00 miFog/Mist54°F51°F94%1013.5 hPa

Wind History from DVO (wind in knots)
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SE4CalmCalmCalmSW3SE6S8CalmS5SE9SE9SE11SE10SE7
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3SE7SE7E6SE7SE7SE5E7CalmCalmSE6CalmSE5SE7SE6SE3E5CalmCalmCalmCalmCalm

Tide / Current Tables for Bolinas Lagoon, California
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Bolinas Lagoon
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Thu -- 01:52 AM PST     1.62 feet Low Tide
Thu -- 03:39 AM PST     Moonset
Thu -- 07:24 AM PST     Sunrise
Thu -- 07:30 AM PST     4.39 feet High Tide
Thu -- 02:07 PM PST     Moonrise
Thu -- 03:19 PM PST     -0.11 feet Low Tide
Thu -- 05:17 PM PST     Sunset
Thu -- 09:43 PM PST     3.08 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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21.71.61.92.43.23.94.34.443.42.51.60.80.2-0.1-00.41.11.82.533.12.9

Tide / Current Tables for Point Reyes, California Current
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Point Reyes
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Thu -- 02:25 AM PST     0.00 knots Slack
Thu -- 03:41 AM PST     Moonset
Thu -- 05:27 AM PST     0.78 knots Max Flood
Thu -- 07:26 AM PST     Sunrise
Thu -- 08:20 AM PST     -0.00 knots Slack
Thu -- 11:39 AM PST     -1.39 knots Max Ebb
Thu -- 02:09 PM PST     Moonrise
Thu -- 03:42 PM PST     0.00 knots Slack
Thu -- 05:18 PM PST     Sunset
Thu -- 06:42 PM PST     1.02 knots Max Flood
Thu -- 10:02 PM PST     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-0.6-0.4-0.10.20.50.80.70.50.2-0.4-0.9-1.3-1.4-1.2-0.8-0.40.20.7110.90.50-0.4

Weather Map and Satellite Images
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GOES Local Image of CentralWestCoast    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Wind Forecast for San Francisco/Monterey Bay Area, CA (11,2,3,4)
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Ground Weather Radar Station Sacramento, CA
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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.