Saturday, November18, 2017 L-36.com


Marine Weather and Tides
Lagunitas-Forest Knolls, 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 6:54AMSunset 4:57PM Saturday November 18, 2017 11:21 AM PST (19:21 UTC) Moonrise 6:55AMMoonset 5:34PM 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- 829 Am Pst Sat Nov 18 2017
Today..NE winds 5 to 15 kt. Wind waves 1 to 3 ft. NW swell 2 to 4 ft at 12 seconds.
Tonight..N winds 10 kt. Wind waves 2 ft or less. NW swell 3 to 5 ft at 10 seconds.
Sun..NW winds 10 kt. Wind waves 2 ft or less. NW swell 2 to 4 ft at 13 seconds.
Sun night..NW winds 10 kt. Wind waves 2 ft or less. NW swell 2 to 3 ft at 14 seconds. Slight chance of rain after midnight.
Mon..E winds 5 to 15 kt. Wind waves 1 to 3 ft. NW swell 3 to 5 ft at 14 seconds. Chance of rain.
Tue..NE winds 10 to 20 kt. Wind waves 2 to 4 ft. NW swell 4 to 6 ft. Slight chance of rain.
Wed..N winds 10 kt. Wind waves 2 ft or less. NW swell 5 to 6 ft. Slight chance of rain.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 2 to 4 ft with a dominant swell period of 10 seconds. Across the bar...combined seas 3 to 5 ft with a dominant swell period of 10 seconds. Maximum ebb current of 1.9 knots at 03:48 pm Saturday and 0.9 knots at 04:24 am Sunday.
PZZ500 829 Am Pst Sat Nov 18 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Light to moderate east/northeast winds this morning, turning more northerly by the afternoon. Winds will switch to southerly over the northern waters Sunday night and Monday then increase on Tuesday for the northern waters. Winds over the southern waters will remain light to moderate northwest. Light to moderate seas through the weekend.

7 Day Forecast for Marine Location Near Lagunitas-Forest Knolls, 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 181717
afdmtr
area forecast discussion
national weather service san francisco bay area
917 am pst Sat nov 18 2017

Synopsis Dry and seasonably cool weather can be expected
through the weekend. The next system will bring rain chances late
Sunday night through Monday, mainly across the north bay.

Additional rainfall is possible at times in the north bay for
much of next week, but most of our area will likely see dry and
warm weather.

Discussion As of 7:45 am pst Saturday... Much cooler start to
the day versus 24-hours ago, primarily as a result of post frontal
cold air advection aloft and clear skies overnight. Temperatures
are generally 5 to 15 degrees cooler as of 7am this morning, with
the coldest remote, elevated locations in the upper 20s to low
30s. The north bay communities of santa rosa and napa are
experience temperatures just a degree or two above freezing as
well. Elsewhere, locations near the water are actually warmest,
with san francisco itnl airport a relatively warm 48 degrees this
morning. Temperatures today will generally warm to near to
slightly below seasonal temperatures, with upper 50s to mid 60s
forecast.

The night shift forecast appears on track this morning, so no
updates are planned until the afternoon forecast package.

Forecast models are showing a general weakening trend regarding
the next cold front that will arrive in extreme northwestern
california on Monday. Previous forecast model runs showed
precipitation extending beyond the san francisco bay area,
however, the latest runs show the bulk of the (now lesser amounts
of) precipitation remaining north of the golden gate and over the
north bay. Thus, the forecast challenge of the day afternoon
forecast package will be to look for any kind of
consistency confidence between the models regarding the next
system's amount, intensity, trajectory and timing. Forecast models
are also showing a slowing, drying trend for the weaker, mid week
system. In general, both of these systems, using previous or
current data, appear weaker than the typical wet season system,
and much weaker than last system that moved through and brought
daily record rainfall amounts earlier this week.

Previous discussion As of 3:00 am pst Saturday... Cool
conditions this morning with many places at this hour in the 30s
and 40s. In fact, many spots over the north bay have dropped into
the lower 30s and could see another degree or two drop by sunrise.

Still waiting for fog to form over the north bay, although that
may be very limited. The cooler conditions will also lead to
patchy frost.

A building ridge of high pressure will combine with an offshore
flow to bring dry weather to our entire CWA both today and
tomorrow. Highs will be in the upper 50s to the mid 60s with lows
Sunday morning forecast to be close to this morning's values.

Patchy frost will again be possible.

The synoptic patter will undergo a change as a moist flow takes
aim on the west coast. Models over the past few days have been
trending drier by pushing the moisture farther to the north as a
ridge of high pressure builds along the coast from the south. This
will lead to the bulk of the rain staying to our north with the
southern extent into a portion of our cwa. Although there remains
disagreement on the southern extent of the rain plus which day,
there is general agreement that for most of next week
precipitation will be possible over the north bay with
diminishing chances heading to the south. Definitely possible that
much of our CWA stays dry for all of the days.

Rainfall amounts by Friday will range from 1 4" to 3 4" for the
north bay to near zero for the southern third. Locations around
san francisco bay can expect 0.05" to 0.15". Temperatures will
also be warmer -- 60s and 70s.

Longer range outlook does bring a major atmospheric river into our
region for the remainder of the month.

Aviation As of 9:16 am pst Saturday... For 18z tafs. High
pressure will dominate over the region today, resulting inVFR
conditions. Few-sct high clouds will stream in through the day.

Light and variable winds this morning, turning W NW by this
afternoon, remaining less than 10 knots.

High confidence
vicinity of ksfo...VFR. Light E SE winds through 20-21z, then
turning NW W between 5-8 knots through the evening.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR. Mainly clear skies. Light winds,
below 10 knots.

Marine As of 09:08 am pst Saturday... Light to moderate
east northeast winds this morning, turning more northerly by the
afternoon. Winds will switch to southerly over the northern
waters Sunday night and Monday then increase on Tuesday for the
northern waters. Winds over the southern waters will remain light
to moderate northwest. Light to moderate seas through the
weekend.

Mtr watches warnings advisories
Tday None.

Public forecast: drp
aviation: bam
marine: bam
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
46237 - San Francisco Bar, CA (142) 15 mi51 min 57°F4 ft
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 16 mi91 min E 9.7 G 12 54°F 56°F4 ft1023.6 hPa (+0.3)
TIBC1 - Tiburon Pier, San Francisco Bay, CA 17 mi69 min NW 6 50°F 1024 hPa
46013 - Bodega Bay - 48NM North Northwest of San Francisco, CA 35 mi41 min E 7.8 G 9.7 52°F 57°F1024.2 hPa43°F
46214 - Point Reyes, CA (029) 39 mi51 min 60°F7 ft
SFXC1 - San Francisco Bay Reserve, CA 41 mi96 min S 2.9 53°F 1024 hPa44°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 43 mi91 min NE 12 G 14 56°F 59°F7 ft1023.1 hPa (+0.3)

Wind History for Point Reyes, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Novato / Gnoss Field, CA15 mi26 minVar 310.00 miFair55°F35°F47%1024.4 hPa
Petaluma Municipal Airport, CA20 mi26 minN 010.00 miFair54°F37°F54%1024 hPa

Wind History from DVO (wind in knots)
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Last 24hrCalmCalmCalmN5N5NW4Calm--SE4S3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmN3Calm
1 day agoSW4CalmSW4SW6SW8W7CalmCalmCalmCalmNW14
G19
W12W10NW11W10W7
G12
CalmCalmCalmCalmCalmN5N6NW9
2 days agoCalm5SE5SE6SE7SE11SE8S6
G14
SE55SE6
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G20
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G14
N5N4W83CalmCalmCalmCalmCalmCalmSW4

Tide / Current Tables for Bolinas Lagoon, California
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Bolinas Lagoon
Click for Map
Sat -- 03:42 AM PST     New Moon
Sat -- 05:15 AM PST     1.34 feet Low Tide
Sat -- 06:54 AM PST     Sunrise
Sat -- 06:54 AM PST     Moonrise
Sat -- 10:40 AM PST     4.20 feet High Tide
Sat -- 04:56 PM PST     Sunset
Sat -- 05:34 PM PST     Moonset
Sat -- 06:02 PM PST     -0.23 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
3.332.621.61.41.522.83.54.14.23.93.22.41.40.5-0-0.200.61.42.32.9

Tide / Current Tables for Point Reyes, California Current
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Point Reyes
Click for Map
Sat -- 12:05 AM PST     -0.00 knots Slack
Sat -- 02:27 AM PST     -0.76 knots Max Ebb
Sat -- 03:42 AM PST     New Moon
Sat -- 05:52 AM PST     0.00 knots Slack
Sat -- 06:56 AM PST     Sunrise
Sat -- 06:56 AM PST     Moonrise
Sat -- 08:37 AM PST     0.82 knots Max Flood
Sat -- 11:28 AM PST     -0.00 knots Slack
Sat -- 02:35 PM PST     -1.34 knots Max Ebb
Sat -- 04:57 PM PST     Sunset
Sat -- 05:35 PM PST     Moonset
Sat -- 06:34 PM PST     0.00 knots Slack
Sat -- 09:36 PM PST     1.07 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.1-0.5-0.7-0.7-0.6-0.30.10.50.80.80.60.2-0.3-0.9-1.3-1.3-1.1-0.8-0.30.30.811.10.9

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 (14,3,4,5)
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Ground Weather Radar Station Sacramento, 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.