Friday, December15, 2017 L-36.com


Marine Weather and Tides
Mountain View, 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 7:15AMSunset 4:53PM Friday December 15, 2017 6:06 AM PST (14:06 UTC) Moonrise 4:46AMMoonset 3:33PM Illumination 8% Phase: Waning Crescent; Moon at 27 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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PZZ530 San Pablo Bay Suisun Bay The West Delta And San Francisco Bay North Of The Bay Bridge- 240 Am Pst Fri Dec 15 2017
.small craft advisory in effect from Saturday morning through late Saturday night...
Today..NE winds 10 kt. Patchy fog in the morning.
Tonight..NW winds 5 to 15 kt.
Sat..N winds 15 to 25 kt with occasional gusts to 35 kt.
Sat night..N winds 15 to 25 kt.
Sun..NE winds 15 to 25 kt...becoming east 10 kt.
Mon..NE winds 10 kt.
Tue..NE winds 5 kt...becoming sw.
PZZ500 240 Am Pst Fri Dec 15 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Light to moderate northerly winds will prevail through the morning and early afternoon today. A cold front is forecast to move from northwest to southeast beginning this evening, bringing increasing northwesterly winds. Gale force winds are likely across all outer water zones beginning late tomorrow night through at least Sunday morning. Winds are expected to decrease by Sunday evening into Monday morning. The strong and gusty winds will create very steep wind waves and fresh swell, creating very rough and hazardous seas through the majority of the weekend.

7 Day Forecast for Marine Location Near Mountain View, CA
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location: 37.45, -122.06     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 151215
afdmtr
area forecast discussion
national weather service san francisco bay area
415 am pst Fri dec 15 2017

Breezy conditions likely late Friday through Sunday morning...

Elevated fire danger particularly for higher elevation
locations for the same time...

Synopsis Dry weather will continue into next week. A mainly
dry cold front will sweep south over the area late Friday night
and early Saturday morning which then increases n-ne winds along
the ridges and peaks Saturday.

Discussion As of 2:42 am pst Friday... Change is literally on
the horizon, more directly the northern horizon. After a period of
persistent high pressure it's finally weakening as an upper level
trough and weak surface front approach the region. The offshore
gradient has weakened as well. Last night the sfo-wmc gradient sat
at 13 mb and now it's down to 8 mb. Winds are much weaker as a
result. One interesting item of note is the continued dry airmass
over the region, especially from 925mb-550mb. Santa rita peak and
chews ridge are currently 7% and 13% respectively. Once again, a
different story in the valleys with higher humidity, cooler
temperatures and even patchy fog for the N and E bay valleys.

For today... Another day of above normal temperatures as a cold
front approaches from the north. MAX temps will be close to
yesterday's values and in the mid 60s to mid 70s with a few
interior locations near 80 for monterey san benito cty. Latest
model guidance brings the cold front into the north bay 00z and
then slowly southward tonight. As mentioned on previous
discussions, associated moisture will remain north of the bay
area. More importantly, the offshore gradient ramps back up with
very gusty winds. Local WRF model continues to show winds of 15-30
mph with gusts exceeding 50 mph tonight through early Sunday.

Winds will be strongest above 1000 feet, especially N and E bay
hills. A wind advisory will remain in effect from 10 pm tonight
through 10 am Sunday. The offshore flow will also result in low
rh. The combination of winds and low rh will result in very
critical fire weather conditions. A red flag warning is now in
effect. See fire section below for more details.

Post frontal conditions will also bring slightly cooler
temperatures Saturday and Sunday, but still several degrees above
normal for mid december. The offshore flow pressure gradient
relaxes on Sunday resulting in weakening winds.

500mb heights and 850mb temps rebound slightly on Monday Tuesday
with warmer weather. Models still continue to struggle with the
much anticipated mid-week system. Run to run reliability of the
models has been much less than desire. 00z run continues to show
a drier solution with better precip chances NE of the bay area and
more over far norcal and the sierra. Confidence stills remains
low and will not include any mention of rain. If we don't get any
precip the middle of next week it's not looking good. The GFS and
ec build a highly amplified pattern with high pressure over most
of the west coast. Interesting factoid, the ec is forecasting
500mb heights of near 588 dam around dec 22 23. That would rival
all time record values for soundings at koak.

Aviation As of 3:59 am pst Friday... For 12z tafs. Once again,
starting off the day with mostly clear skies, except for a few
high clouds drifting into the region. Visibilities at ksts have
been seesawing back and forth due to patchy dense fog in the area.

Expect fog to burn off by 15-16z. Light winds will continue this
morning and into the afternoon before winds increase and turn
westerly northwesterly along and behind a cold front that is
forecast to pass through the bay area tonight. Winds will likely
be gusty for terminals along the immediate coast overnight. There
could also be brief period of low CIGS along the cold front
tonight. Not enough confidence to include in tafs.

Moderate to high confidence.

Vicinity of ksfo...VFR. Light and variable winds today with a few
high clouds. Westerly winds increase tonight along a cold front,
becoming gusty after sunset. Gusts may approach 30 kts around and
after midnight.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR. Moderate east southeast winds will
likely continue this morning through the salinas valley, 10-15
kts. Otherwise, light winds will turn onshore this afternoon and
increase late tonight.

Fire weather As of 2:42 am pst Friday... The fire weather watch
has been upgraded to a red flag warning from 10 pm Friday through
10 am Sunday. Offshore flow is forecast to develop behind the
front tonight into Saturday. Latest models do show some modest rh
recovery early tonight then dropping through the day and poor
recoveries Saturday night. It's fairly common to have lower rh on
night number two behind a front with developing offshore flow.

May not technically hit rh criteria for tonight, but decided to
keep fire weather concerns going given gusty winds, lack of recent rain,
very low rh (single digits) the last few nights and near record
values of ercs for the N bay mts and santa cruz diablo psas. Areas
of greatest concern will be above 1000 feet. Winds may be a tad
weaker on Saturday night, but rh recoveries worse. For what it's
worth, fire weather concerns are not that unusual for this time
of year. December 16, 2013, a wildfire broke out in big sur called
the pfeiffer fire.

Marine As of 2:42 am pst Friday... Light to moderate northerly
winds will prevail through the morning and early afternoon today.

A cold front is forecast to move from northwest to southeast
beginning this evening, bringing increasing northwesterly winds.

Gale force winds are likely across all outer water zones beginning
late tomorrow night through at least Sunday morning. Winds are
expected to decrease by Sunday evening into Monday morning. The
strong and gusty winds will create very steep wind waves and fresh
swell, creating very rough and hazardous seas through the
majority of the weekend.

Mtr watches warnings advisories
Tday Sca... Pt arena to pigeon pt 10-60 nm from 12 pm
sca... Pt arena to pt reyes 0-10 nm from 3 pm
public forecast: mm
aviation marine: bam
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
RTYC1 - 9414523 - Redwood City, CA 9 mi48 min SSE 1 G 2.9 43°F 54°F1021.7 hPa
AAMC1 - 9414750 - Alameda, CA 26 mi54 min E 1 G 1.9 47°F 54°F1021.4 hPa
LNDC1 27 mi66 min Calm G 1.9 48°F 1021.2 hPa (+0.0)
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 28 mi48 min SE 2.9 G 4.1
OBXC1 29 mi48 min 49°F 45°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 29 mi48 min SSE 2.9 G 4.1 47°F 1021.2 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 30 mi48 min NW 5.1 G 7 52°F 1020.3 hPa
PXSC1 30 mi48 min 53°F 44°F
FTPC1 - 9414290 - San Francisco, CA 33 mi54 min N 12 G 15 52°F 53°F1021.3 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 35 mi48 min N 7 G 8.9 50°F 1021.4 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 37 mi57 min WNW 5.1 49°F 1021 hPa
RCMC1 - 9414863 - Richmond, CA 38 mi54 min NNE 6 G 8.9 53°F 54°F1021 hPa
46237 - San Francisco Bar, CA (142) 38 mi66 min 54°F8 ft
MZXC1 - 9415102 - Martinez-Amorco CA 41 mi48 min ESE 2.9 G 4.1 44°F 53°F1022.3 hPa44°F
PCOC1 - 9415144 - Port Chicago, CA 42 mi48 min ESE 5.1 G 5.1 42°F 52°F1022.1 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 42 mi48 min S 2.9 G 4.1 43°F 1022.2 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 43 mi48 min E 15 G 18 48°F 1021.3 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 44 mi76 min NE 7.8 G 9.7 56°F 59°F8 ft1019.8 hPa (+0.0)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 46 mi76 min E 14 G 19 56°F 53°F8 ft1020.2 hPa (-0.8)
ELXC1 - Elkhorn Slough Reserve, CA 47 mi81 min ESE 2.9 50°F 1020 hPa29°F
46092 - MBM1 48 mi46 min NE 12 54°F 58°F1019.7 hPa (-0.5)
46042 - MONTEREY - 27NM West of Monterey Bay, CA 49 mi76 min E 7.8 G 9.7 57°F 58°F8 ft1020 hPa (-0.4)

Wind History for Redwood City, CA
(wind in knots)    EDIT      (on/off)   Help
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Mountain View, Moffett Field, CA1 mi70 minN 010.00 miFair41°F35°F79%1022 hPa
San Jose, San Jose International Airport, CA9 mi73 minN 010.00 miFair40°F34°F79%1021.6 hPa
San Carlos Airport, CA11 mi71 minN 08.00 miFair43°F39°F87%1021.7 hPa
Hayward, Hayward Air Terminal, CA15 mi72 minE 38.00 miFair42°F32°F68%1022.4 hPa
Oakland, Metro Oakland International Airport, CA19 mi73 minSSE 36.00 miFog/Mist40°F37°F93%1021.4 hPa
San Francisco, San Francisco International Airport, CA20 mi70 minS 38.00 miA Few Clouds47°F39°F77%1021.2 hPa
Livermore, Livermore Municipal Airport, CA21 mi73 minN 06.00 miFog/Mist35°F30°F85%1021.8 hPa
Half Moon Bay Airport, CA24 mi71 minN 010.00 miFair39°F33°F81%1019.3 hPa

Wind History from NUQ (wind in knots)
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Last 24hrCalmCalmCalmCalmCalmCalmN3N6N4N3N3CalmCalmCalmCalmSE4CalmCalmCalmCalmSW3CalmCalmCalm
1 day agoW3CalmCalmCalmW3N4N6NW4NW5NW4N3CalmW3CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm
2 days agoCalmCalmCalmCalmCalmN3N6N4N4NW5CalmNW4CalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalmCalm

Tide / Current Tables for Calaveras Point, west of, San Francisco Bay, California
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Calaveras Point
Click for Map
Fri -- 04:42 AM PST     2.32 feet Low Tide
Fri -- 04:45 AM PST     Moonrise
Fri -- 07:15 AM PST     Sunrise
Fri -- 10:21 AM PST     8.97 feet High Tide
Fri -- 03:33 PM PST     Moonset
Fri -- 04:51 PM PST     Sunset
Fri -- 05:48 PM PST     -0.10 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
76.14.73.42.52.43.14.66.37.98.98.886.44.52.610.1-0.10.623.75.56.9

Tide / Current Tables for Dumbarton Point 2.3 mi NE, South San Francisco Bay, California Current
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Dumbarton Point 2.3 mi NE
Click for Map
Fri -- 03:04 AM PST     -0.67 knots Max Ebb
Fri -- 04:45 AM PST     Moonrise
Fri -- 05:07 AM PST     0.00 knots Slack
Fri -- 07:15 AM PST     Sunrise
Fri -- 07:45 AM PST     1.12 knots Max Flood
Fri -- 10:35 AM PST     -0.01 knots Slack
Fri -- 03:15 PM PST     -1.29 knots Max Ebb
Fri -- 03:33 PM PST     Moonset
Fri -- 04:51 PM PST     Sunset
Fri -- 06:01 PM PST     0.00 knots Slack
Fri -- 08:52 PM PST     1.38 knots Max Flood
Fri -- 11:55 PM PST     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.3-0.5-0.6-0.7-0.6-0.10.611.10.90.4-0.2-0.6-1-1.2-1.3-1.2-0.8-00.81.21.41.20.7

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 (9,2,3,4)
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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.