Monday, November20, 2017 L-36.com


Marine Weather and Tides
San Mateo, 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 6:53AMSunset 4:56PM Sunday November 19, 2017 9:57 PM PST (05:57 UTC) Moonrise 7:49AMMoonset 6:12PM Illumination 2% Phase: Waxing Crescent; Moon at 1 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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PZZ531 San Francisco Bay South Of The Bay Bridge- 923 Pm Pst Sun Nov 19 2017
Tonight..W winds 5 to 15 kt...becoming southeast after midnight.
Mon..S winds 10 kt. Slight chance of rain in the morning.
Mon night..N winds 10 kt.
Tue..N winds 10 kt.
Tue night..N winds 10 kt.
Wed..N winds 10 kt.
Thanksgiving day..NW winds 5 to 15 kt.
Fri..N winds 5 to 15 kt. Slight chance of rain.
PZZ500 923 Pm Pst Sun Nov 19 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... The eastern edge of a very moist sub-tropical flow will overlap the northern coastal waters through early this week. A warm frontal boundary connected to this moist flow will approach the coastal waters Monday and become nearly stationary while another warm front to the southwest advances toward it and the bay area. By late week into early next week a cold front will move southeastward over the coastal waters. Seas are expected to remain light to moderate through the first part of next week.

7 Day Forecast for Marine Location Near San Mateo, CA
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location: 37.59, -122.31     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 200458
afdmtr
area forecast discussion
national weather service san francisco bay area
858 pm pst Sun nov 19 2017

Synopsis Look for a weather system to bring rain chances late
tonight and Monday, mainly across the north bay. There is a slight
chance of additional rainfall at times in the north bay for much
of this week, but most of our area is forecast to be warm and dry
through thanksgiving.

Discussion As of 9:00 pm pst Sunday... Very comfortable day
across our entire region with many locations into the lower to mid
60s. Considering that mid-november can often be rainy, breezy, and
cool, conditions were quite mild for the time of year. Satellite
and radar both show the leading edge of moisture approaching the
north bay. This is associated with a system focused farther to
the north. Along our region, the southern extent of the moisture
will move into napa sonoma tonight and potentially drop into part
of the san francisco bay area overnight into Monday morning. Rain
will then retreat farther to the north by the afternoon as a ridge
of high pressure builds in from the south. Rainfall amounts will
be minor -- less than a quarter of an inch for most of the north
bay. Around san francisco bay less than 0.05" is likely.

The building ridge will lead to warmer temperatures with 80s
expected to return to parts of monterey and san benito counties
on Tuesday. With an offshore gradient in place, the warmer weather
will even make it to the coast with mid 70s to lower 80s likely.

Farther to the north, temperatures will warm, but not nearly as
much due to the closer proximity to moisture. Highs will generally
be in the upper 60s to the lower 70s.

Continued warm conditions are forecast through thanksgiving day
along with mostly dry conditions. Temperatures will lower by the
end of the week as the ridge shifts off to the east. No sign of
any weather hazards with the rain expected to stay mostly to our
north and only a slight chance of precipitation north of san
francisco. Latest model runs are also running drier than the ones
the day crew had access to.

Previous discussion After active weather earlier this week the
weekend will end quietly. Filtered sunshine blanket the bay area
this afternoon with mild temperatures.

Latest surface analysis shows a large area of high pressure over
the region and just off the west coast. Much farther to the NW a
surface low is located near 31.30n 149.90w with a front extending
to the NE and to the sw. Just south of the SW extending frontal
boundary is a very impressive moisture plume with pwats around two
inches. Over the next 24 hours or so a battle between the ridge
and frontal boundary will unfold. As of now, the models have the
ridge of high pressure winning out. That being said, enough
moisture and warm air advection will move over the north bay to
warrant a few showers in the forecast late tonight and Monday.

Rainfall amounts will generally be light with a tenth to a
quarter possible over the north bay. There could be a few spots
near the sonoma mendocino line that could be over one quarter of
an inch. Did cut back on rain chances south of the of the golden
gate, but there could be a stray shower early tonight before the
ridge builds in tomorrow. South of sf bay is expected to remain
dry.

Monday night into Tuesday ridging builds across the bay area
bringing dry conditions but more notably well above normal
temperatures Tuesday and Wednesday. Current forecast will have
monterey san benito counties MAX temps eclipsing 80 degrees across
the interior and 70s at the coast. Elsewhere across the CWA highs
will be in the upper 60s and 70s. That will put MAX temps 10-15
degrees above normal for late november.

Ridge of high pressure weakens on thanksgiving with a slight drop
in temperatures. The weakening ridge will also allow for moisture
from the north to sag southward. Medium range models have varying
solutions on thanksgiving with the canadian showing precip to the
golden gate, GFS is north of golden gate and ECMWF is north of
santa rosa. In all, rainfall amounts are light as well-tenth to a
quarter. Given the uncertainty, will at least keep a slight
chance for showers over the north bay. The rest of the bay area
will likely have a dry and mild thanksgiving, especially south of
san jose.

The longer range models indicate the ridge will shift far enough
to the east late in the week to allow precipitation to gradually
spread into our forecast area between Thursday night and next
weekend. However, there are considerable model differences
regarding timing and location of rainfall late in the extended
forecast period.

Aviation As of 6:31 pm pst Sunday...VFR persists at the terminals
this evening though initially high cloud bases from today will
steadily lower tonight and Monday. A very moist, milder, and stable
sw flow from the sub-tropics primarily displacing to the pacific
northwest and northernmost california this week will brush the north
bay with light-moderate rain beginning tonight, while it remains
mainly dry to dry elsewhere.

The WRF model indicates 20-30 knot SW winds at the 925 mb and 850
mb levels over the north bay counties starting early Monday morning
and lasting until early Monday afternoon. With a stable lower level
air mass in place and lighter surface winds though marginal low level
wind shear (llws) is possible at ksts Monday. Will go ahead and amend
ksts TAF shortly to add llws, just need to look it over once again
and fine tune the timing. Lower level winds are much less robust over
the remaining bay area and areas to the south Monday thus llws is not
expected to the south.

Vicinity of ksfo... Light wind,VFR. Cloud bases lowering tonight and
Monday, dry runway. Low to moderate confidence.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... Light e-se winds developing this evening,
could be near 10 knots salinas valley Monday morning.VFR and dry.

Moderate to high confidence.

Marine As of 5:08 pm pst Sunday... A storm system currently off
the british colombia coast has resulted in a split windflow
pattern over the coastal waters, where winds are out of the south
for the northern waters and out of north for the southern waters.

Winds will eventually turn more southerly or become calm over the
southern coastal waters by Monday morning. The associated cold
front will stall off the northern california coast, which will
keep winds southerly through at least mid week, especially for the
northern waters. These southerly winds may become moderate to
locally gusty over the northern outer waters. Seas are expected to
remain light to moderate through the first part of next week.

Mtr watches warnings advisories
Tday None.

Public forecast: bell mm
aviation: canepa
marine: bam
visit us at

Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
RTYC1 - 9414523 - Redwood City, CA 8 mi39 min SSE 2.9 G 4.1 56°F 59°F1019.4 hPa
AAMC1 - 9414750 - Alameda, CA 13 mi39 min E 1.9 G 2.9 57°F 58°F1019.4 hPa
LNDC1 14 mi45 min ESE 2.9 G 4.1 58°F 1018.8 hPa
OBXC1 15 mi39 min 57°F 52°F
PXSC1 15 mi39 min 59°F 52°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 15 mi39 min SSE 1.9 G 2.9
OKXC1 - 9414776 - Oakland (Berth 34), CA 15 mi39 min SSE 1 G 1.9 57°F 1019 hPa
FTPC1 - 9414290 - San Francisco, CA 17 mi39 min SW 1.9 G 1.9 55°F 58°F1019.3 hPa
46237 - San Francisco Bar, CA (142) 22 mi57 min 57°F3 ft
PPXC1 - 9414847 - Richmond (Point Potrero), CA 22 mi39 min SSE 1 G 1.9 58°F 1019.3 hPa
RCMC1 - 9414863 - Richmond, CA 24 mi39 min E 1.9 G 1.9 57°F 58°F1018.9 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 30 mi67 min ESE 3.9 G 5.8 56°F 57°F3 ft1018.7 hPa (-0.3)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 32 mi39 min SE 1.9 G 4.1 57°F 1018.7 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 32 mi39 min SSW 1.9 G 1.9 55°F 58°F1019.4 hPa47°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 34 mi67 min ESE 7.8 G 7.8 58°F 59°F3 ft1018.1 hPa (-0.6)
PCOC1 - 9415144 - Port Chicago, CA 35 mi39 min N 1 G 1.9 57°F 58°F1019 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 38 mi39 min SSE 2.9 G 4.1 55°F 1019.1 hPa
SFXC1 - San Francisco Bay Reserve, CA 45 mi72 min Calm 49°F 1019 hPa45°F
PRYC1 - 9415020 - Point Reyes, CA 45 mi39 min SE 2.9 G 5.1 56°F1018.3 hPa

Wind History for Redwood City, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
San Francisco, San Francisco International Airport, CA3 mi61 minS 510.00 miMostly Cloudy56°F46°F72%1018.9 hPa
San Carlos Airport, CA5 mi68 minVar 310.00 miMostly Cloudy55°F48°F77%1019.3 hPa
Oakland, Metro Oakland International Airport, CA9 mi64 minN 010.00 miMostly Cloudy53°F50°F89%1019.1 hPa
Hayward, Hayward Air Terminal, CA11 mi63 minESE 310.00 miFair56°F46°F70%1019.8 hPa
Half Moon Bay Airport, CA11 mi62 minN 010.00 miFair50°F46°F88%1017.9 hPa
Palo Alto Airport, CA13 mi70 minN 010.00 miMostly Cloudy55°F50°F82%1019.3 hPa
Mountain View, Moffett Field, CA18 mi61 minN 010.00 miFair56°F48°F77%1019.6 hPa

Wind History from SFO (wind in knots)
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Last 24hrS4CalmNW3W3W4CalmCalmS3SW3CalmCalmCalmE3E3NE6N5CalmCalmN3NW4NW7W6SE3S5
1 day agoNE8S3CalmSW3W6W3CalmSW4SW3S3S4SE6E5NE4CalmCalmN3CalmW10W7W6W6W5Calm
2 days agoS6W10W8W8W5W6W9W6NW5W5W5W5N6N9N9NW4N5N10N14N12NE10NE8NE10NE11

Tide / Current Tables for Coyote Point Marina, San Francisco Bay, California
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Coyote Point Marina
Click for Map
Mon -- 01:47 AM PST     6.19 feet High Tide
Mon -- 06:54 AM PST     Sunrise
Mon -- 06:58 AM PST     2.79 feet Low Tide
Mon -- 08:41 AM PST     Moonrise
Mon -- 12:34 PM PST     7.28 feet High Tide
Mon -- 04:54 PM PST     Sunset
Mon -- 06:55 PM PST     Moonset
Mon -- 07:37 PM PST     -0.33 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
5.166.25.74.83.93.12.83.14.15.46.57.27.26.55.23.51.80.6-0.2-0.30.31.52.9

Tide / Current Tables for San Mateo Bridge, South San Francisco Bay, California Current
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San Mateo Bridge
Click for Map
Mon -- 02:50 AM PST     -0.00 knots Slack
Mon -- 05:21 AM PST     -0.89 knots Max Ebb
Mon -- 06:54 AM PST     Sunrise
Mon -- 08:14 AM PST     0.00 knots Slack
Mon -- 08:41 AM PST     Moonrise
Mon -- 10:46 AM PST     1.13 knots Max Flood
Mon -- 01:50 PM PST     -0.00 knots Slack
Mon -- 04:54 PM PST     Sunset
Mon -- 05:28 PM PST     -1.75 knots Max Ebb
Mon -- 06:54 PM PST     Moonset
Mon -- 08:58 PM PST     0.00 knots Slack
Mon -- 11:49 PM PST     1.65 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.61.30.7-0.1-0.6-0.9-0.8-0.5-0.10.511.10.90.5-0.1-0.7-1.3-1.7-1.7-1.3-0.700.91.5

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 (0,6,7,8)
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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.