Thursday, March21, 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 7:10AMSunset 7:24PM Thursday March 21, 2019 2:39 PM PDT (21:39 UTC) Moonrise 7:27PMMoonset 6:57AM Illumination 99% Phase: Waning Gibbous; Moon at 16 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- 215 Pm Pdt Thu Mar 21 2019
.small craft advisory in effect from late tonight through late Friday night...
Rest of today..W winds around 10 kt. Wind waves 2 ft or less. W swell 1 to 2 ft at 20 seconds and W 4 to 6 ft at 13 seconds.
Tonight..SW winds 5 to 10 kt. Wind waves 2 ft or less. W swell 2 to 4 ft at 20 seconds and W 3 to 6 ft at 12 seconds.
Fri..S winds 15 to 25 kt with gusts up to 30 kt. Wind waves 3 to 4 ft. W swell 4 to 7 ft at 18 seconds and W 2 to 3 ft at 11 seconds. Showers.
Fri night..W winds 10 to 20 kt with gusts up to 30 kt. Wind waves 3 to 4 ft. W swell 7 to 10 ft at 17 seconds and S 1 to 2 ft at 14 seconds. A chance of showers.
Sat..NW winds 10 to 15 kt. Wind waves 2 ft or less. W swell 9 to 12 ft at 16 seconds and S 1 to 2 ft at 13 seconds.
Sat night..NW winds 5 to 15 kt. Wind waves 2 ft or less. W swell 9 to 12 ft at 16 seconds and S 1 to 2 ft at 13 seconds.
Sun..S winds 5 to 15 kt. Wind waves 2 ft or less. W swell 6 to 9 ft and S 1 to 2 ft. A chance of showers.
Mon..S winds 5 to 15 kt. Wind waves 2 ft or less. W swell 6 to 8 ft and sw 1 to 2 ft. Showers likely.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 6 to 8 ft with a dominant of 12 seconds. Across the bar...combined seas 7 to 9 ft with a dominant period of 12 seconds. Maximum ebb current of 3.0 kt at 05:55 pm Thursday and 3.6 kt at 06:07 am Friday.
PZZ500 215 Pm Pdt Thu Mar 21 2019
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Weak transitory ridge over the area through the remainder of the day will result in light to locally breezy west to northwest winds. Winds turn southerly and increase by Sunrise Friday as a frontal system moves in. A moderate west swell will dissipate through the next 24 hours but a different, longer period west swell has already begun to build into the waters this afternoon.


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 212136
afdmtr
area forecast discussion
national weather service san francisco bay area
236 pm pdt Thu mar 21 2019

Synopsis Dry conditions are expected tonight ahead of the next
frontal system that will bring widespread rainfall to the region
tomorrow and tomorrow night. Mainly dry conditions then return
for a majority of the weekend with unsettled weather likely
throughout at least the first half of next week.

Discussion As of 02:36 pm pdt Thursday... Temperatures this
afternoon are a few degrees warmer than this time yesterday with
most areas in the upper 50s to mid 60s, but still running around 5
to 10 degrees cooler than seasonal normals. Satellite imagery and
surface analysis shows partly cloudy skies across the bay area
and central coast with a weak surface low situated to the
southeast of southern monterey county. Conditions remain dry this
afternoon, although cannot rule out a stray shower in the southern
portion of the region. Dry conditions will persist tonight thanks
to some temporary ridging over the eastern pacific.

Rain chances will then return tomorrow morning as the next system
approaches from the gulf of alaska. Precipitation is expected to
arrive along the coast in the early morning before spreading from
northwest to southeast across the region throughout the day. The
bulk of the rainfall is expected over the santa cruz mountains and
northward into the north bay with urban areas seeing around 0.50"
to 0.75", with lesser amounts in the east bay valleys and in the
south bay. The santa cruz mountains and the north bay hills may
see around 1.00" to 1.50". Rainfall amounts will be lower for the
southern half of the region with most locations forecast to
receive less than 0.25". The main frontal boundary is progged to
arrive by tomorrow afternoon and move through the area tomorrow
night. Locally breezy conditions are expected ahead of and in the
wake of the frontal passage with gusts around 35 to 40 mph.

Post frontal showers will persist Friday night before rain
chances diminish Saturday morning. Most of Saturday and Sunday
continue to look dry as the system moves out of the region and a
weak ridge builds in over the eastern pacific on Saturday before
moving eastward over land into Sunday. Daytime high temperatures
are forecast mainly in the upper 50s to low 60s along the coast
Saturday with highs to the mid 60s inland. Inland locations may
rise into the upper 60s on Sunday bringing temperatures closer to
seasonal averages. This dry weather will be short lived as rain
chances return early next week.

Models continue to show an unsettled weather pattern for
california early through mid next week. There is general agreement
between both the deterministic models and ensembles of more
widespread rainfall potential through at least the first half of
next week. Differences remain amongst the models in regards to
timing, amounts, and location of precipitation. Currently, both
the GFS and ECMWF show a large upper low moving in from the gulf
of alaska bringing one round of widespread rainfall to the region by
Monday morning with a second round of precipitation after that,
but with some significant differences between the models in the
overall pattern and location of the upper system. The forecast
will be monitored in the coming days.

Aviation As of 11:00 am pdt Thursday... For 18z tafs.

WidespreadVFR through the day Thursday with generally light to
locally breezy onshore winds. A few lingering cumulus clouds
around the region this afternoon should not bring any impacts.

A storm system approaching from the north will bring lowering
ceilings overnight and will become MVFR beginning sometime between
sunrise and mid morning depending on location. Rain will spread
from northwest to southeast across the day Friday, with rain
possible in the north bay by sunrise. S-se winds will become
breezy to locally gusty in the wind prone spots (ksns salinas
valley, ksjc santa clara valley, coastal gaps such as near ksfo)
throughout tomorrow morning. Improving conditions for the weekend.

Vicinity of ksfo...VFR conditions are expected through the day
today and through tonight ahead of an approaching storm system.

Ceilings will gradually lower overnight through tomorrow morning,
with MVFR ceilings expected throughout at least Friday morning and
afternoon, if not into Friday evening. Winds today will generally
be light but may occasionally become breezy once winds shifts
onshore by the afternoon. Vicinity rain showers will be possible
by sunrise Friday with widespread rain expected by the early
afternoon.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR and light winds through the day
though winds may become occasionally breezy after winds become
onshore by the afternoon. Otherwise, expect gradually lowering
ceilings overnight into Friday morning ahead of the arrival of
rain Friday afternoon evening. Gusty winds are expected through
the salinas valley once winds become SE tomorrow morning.

Cwsu oakland forecast... .

Loss of visuals 1430-1800z
.Confidence: med
the low clouds continue to form along the east bay shore and are
intruding into the approach. This can be seen on the airport cams
and on satellite. Expansion will continue after sunrise. The 18z end
time of my forecast may be pessimistic in holding on to the low
clouds. The late march sun's energy is not quite strong enough for
an early burn off.

Marine As of 02:15 pm pdt Thursday... Weak transitory ridge
over the area through the remainder of the day will result in
light to locally breezy west to northwest winds. Winds turn
southerly and increase by sunrise Friday as a frontal system moves
in. A moderate west swell will dissipate through the next 24
hours but a different, longer period west swell has already begun
to build into the waters this afternoon.

Mtr watches warnings advisories
Tngt Sca... Pt arena to pigeon pt 10-60 nm from 9 pm
sca... Pt arena to pt reyes 0-10 nm from 3 am
sca... Pt reyes to pigeon pt 0-10 nm from 3 am
public forecast: as
aviation: drp
marine: drp
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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 mi40 min 56°F1020.2 hPa (+0.0)
46237 - San Francisco Bar, CA (142) 15 mi70 min 58°F6 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 16 mi40 min W 7.8 G 9.7 54°F 56°F1020.9 hPa (+0.0)
TIBC1 - Tiburon Pier, San Francisco Bay, CA 17 mi77 min Calm 57°F 1020 hPa
RCMC1 - 9414863 - Richmond, CA 18 mi40 min 56°F
FTPC1 - 9414290 - San Francisco, CA 19 mi46 min W 8.9 G 12 55°F 56°F1020.4 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 21 mi40 min SW 8 G 11 57°F 1020.1 hPa (-0.4)
PXOC1 - 9414311 - San Francisco (Pier 1), CA 22 mi40 min W 8.9 G 12 58°F 1018.9 hPa (-0.4)
PXSC1 22 mi40 min 58°F 46°F
OBXC1 24 mi40 min 56°F 48°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 25 mi40 min W 8.9 G 11
OKXC1 - 9414776 - Oakland (Berth 34), CA 25 mi40 min WNW 11 G 12 55°F 1019.9 hPa (-0.4)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 26 mi40 min W 4.1 G 5.1 59°F 1019.5 hPa (-0.5)
AAMC1 - 9414750 - Alameda, CA 27 mi46 min W 4.1 G 5.1 58°F 57°F1020.2 hPa
LNDC1 27 mi40 min WSW 7 G 8 57°F 1019.8 hPa (-0.3)
UPBC1 33 mi40 min WNW 9.9 G 12
MZXC1 - 9415102 - Martinez-Amorco CA 33 mi40 min WNW 8.9 G 11 58°F 56°F1019.5 hPa (-0.6)34°F
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 35 mi40 min W 5.8 G 7.8 55°F1020.3 hPa (+0.0)
PCOC1 - 9415144 - Port Chicago, CA 38 mi40 min W 9.9 G 12 58°F 56°F1019.5 hPa (-0.7)
46214 - Point Reyes, CA (029) 39 mi40 min 57°F8 ft
SFXC1 - San Francisco Bay Reserve, CA 41 mi115 min W 4.1 60°F 1020 hPa42°F
RTYC1 - 9414523 - Redwood City, CA 43 mi40 min N 7 G 8 57°F 60°F1020.2 hPa (-0.7)
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 45 mi40 min NNW 6 G 9.9 60°F 1019.2 hPa (-0.9)

Wind History for Point Reyes, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Novato / Gnoss Field, CA15 mi65 minSW 7 G 1710.00 miPartly Cloudy63°F44°F52%1020 hPa
Petaluma Municipal Airport, CA20 mi65 minWSW 810.00 miFair61°F44°F55%1020 hPa

Wind History from DVO (wind in knots)
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Last 24hrSW12W9SW9SW7--W4CalmSW3CalmSW3CalmCalmNE3CalmCalmCalmCalmN5N4CalmN3N8CalmNW8
1 day ago4SE5S4W12SW9SW3
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CalmSW10E3CalmSE5SE12SE10
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2 days agoE7SE7CalmS54N8N6N10N10N8NW5S4N4CalmS6N6CalmS3CalmCalmE4Calm43

Tide / Current Tables for Bolinas Lagoon, California
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Bolinas Lagoon
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Thu -- 12:31 AM PDT     4.14 feet High Tide
Thu -- 06:55 AM PDT     0.35 feet Low Tide
Thu -- 07:12 AM PDT     Sunrise
Thu -- 07:56 AM PDT     Moonset
Thu -- 12:29 PM PDT     4.28 feet High Tide
Thu -- 07:15 PM PDT     -0.04 feet Low Tide
Thu -- 07:23 PM PDT     Sunset
Thu -- 08:26 PM PDT     Moonrise
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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44.13.72.921.10.50.40.71.62.63.64.24.23.83210.3-00.10.81.92.9

Tide / Current Tables for Point Reyes, California Current
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Point Reyes
Click for Map
Thu -- 01:06 AM PDT     -0.00 knots Slack
Thu -- 03:49 AM PDT     -1.33 knots Max Ebb
Thu -- 07:14 AM PDT     Sunrise
Thu -- 07:17 AM PDT     0.00 knots Slack
Thu -- 07:58 AM PDT     Moonset
Thu -- 10:13 AM PDT     1.28 knots Max Flood
Thu -- 01:17 PM PDT     -0.00 knots Slack
Thu -- 04:10 PM PDT     -1.46 knots Max Ebb
Thu -- 07:24 PM PDT     Sunset
Thu -- 07:45 PM PDT     0.00 knots Slack
Thu -- 08:28 PM PDT     Moonrise
Thu -- 10:39 PM PDT     1.26 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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0.70.1-0.7-1.2-1.3-1.1-0.7-0.20.511.31.20.80.2-0.5-1.2-1.5-1.3-1-0.50.20.81.21.2

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 (17,4,5,8)
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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.