Wednesday, October18, 2017 L-36.com


Marine Weather and Tides
San Lorenzo, 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 7:19AMSunset 6:27PM Wednesday October 18, 2017 1:35 PM PDT (20:35 UTC) Moonrise 5:08AMMoonset 5:18PM Illumination 2% Phase: Waning Crescent; Moon at 28 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- 905 Am Pdt Wed Oct 18 2017
.small craft advisory in effect from 2 pm pdt this afternoon through late tonight...
Today..SW winds 10 kt...increasing to 15 to 25 kt in the afternoon. Patchy smoke.
Tonight..SW winds 15 to 25 kt.
Thu..SW winds 15 to 25 kt.
Thu night..SW winds 10 to 20 kt. Chance of rain in the evening, then chance of showers after midnight.
Fri..W winds 5 to 15 kt.
Sat..W winds 10 kt.
Sun..W winds 10 kt.
PZZ500 905 Am Pdt Wed Oct 18 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Areas of fog this morning across the coastal waters and into the bays. Winds will increase over the bays this afternoon into tonight. A cold front will move across the waters late tomorrow bringing chances of light rain. A moderate to long period mixed northwesterly and southerly swell has arrived with buoys reporting periods of 17 to 18 seconds across the waters. Late Thursday into Friday a large northwesterly swell train will move across he area. This large swell will create hazardous conditions.

7 Day Forecast for Marine Location Near San Lorenzo, CA
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location: 37.65, -122.22     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 181738
afdmtr
area forecast discussion
national weather service san francisco bay area
1038 am pdt Wed oct 18 2017

Synopsis Cooler temperatures are expected today and Thursday
as onshore flow strengthens. A weak early season weather system is
forecast to bring light rain to much of the region from Thursday
afternoon through Thursday night. Dry weather is expected to
return by Friday. A warming trend will begin over the weekend.

Warm and dry weather is expected regionwide early next week.

Discussion As of 09:07 am pdt Wednesday... In response to
increased onshore flow during the past 18 hours or so, the marine
layer has returned at a depth of around 500 feet. With this, low
clouds have also returned to the coast and have spread locally
inland to the valley locations. Patchy fog, dense at times, is
also impacting portions of the region this morning. Look for low
clouds and or patchy fog to persist through the morning before
burning off later as daytime heating takes place. With that said,
some coastal areas may remain under cloud cover through a good
portion of the day. Overall, temperatures today will be cooler
than those on Tuesday, yet should be at or slightly above seasonal
averages before a more significant cool down arrives Thursday
into Friday as a cold front pushes through the region. Only minor
updates have been made this morning to reflect current satellite
and temperature trends. Please see the forecast discussion below
for additional details.

Prev discussion As of 3:35 am pdt Wednesday... Kmux radar is still
showing some weak showers over extreme southern monterey county.

Nothing is being reported at automated gauges, so this is all
likely aloft. Meanwhile satellite imagery shows some high clouds
currently moving over the area with coastal stratus making a
resurgence and starting to spread locally inland over san
francisco as well as into the monterey bay and salinas valley.

Current temperature trends indicate cooler temperatures in most
locations with readings from the lower 40s to the mid 50s. Surface
pressure gradients are now stronger onshore with 1.3 mb from sfo
to sac compared to light offshore (-0.2 mb) yesterday at this
time. There is still a very weak offshore gradient component from
wmc to sfo at 2.2 mb, but this is decreasing.

Today is expected to be cooler across the district but mainly near
the coast as onshore flow ramps up with highs ranging from the
60s at the coast to the 70s and 80s inland. Additional cooling
will occur on Thursday, especially inland, as a weak storm system
approaches the coast and increases cloudiness. Latest models bring
light rain to the sonoma coast by Thursday afternoon, and then
spreads rain across most of the north bay by early evening. The
weakening frontal boundary will then press south of the golden
gate by late Thursday and bring scattered amounts of light rain to
the rest of the bay area Thursday evening and as far south as
monterey county by later Thursday night. The models continue to
trend drier with this system and a blend of recent model output
indicates most locations will pick up less than a tenth of an inch
on Thursday and Thursday night. Locally higher amounts of a
quarter to a third of an inch are possible across northwest sonoma
county. Nearly all models now indicate rain will end by daybreak
Friday.

A warming trend is forecast to begin during the weekend as an
upper level ridge begins to build over the west. The ridge will
then strengthen early next week and light offshore flow will
develop. This will result in warm and dry conditions throughout
the district next Monday and Tuesday with widespread highs in the
80s, even near the coast. The ridge is progged to flatten after
midweek.

Aviation As of 10:38 am pdt Thursday... For 18z tafs.

Widespread stratus along the immediate coast, but is beginning to
retreat from bay area terminals. Stratus over the san francisco
bay is beginning to dissipate with ksfo having gone sct just
recently. Can also see stratus eroding over kmry and ksns. Once
all the stratus clears over land this morning expectingVFR vis
and CIGS through this evening. Wildfires are still burning across
parts of the area, but conditions have improved. There's still a
chance that hz or fu could temporarily reduce visibilities to MVFR
for TAF sites in the vicinity of the fires. Current model
guidance indicates an early return of widespread stratus tonight.

Onshore flow this afternoon with winds 10 to 15 kt possibly
gusting to just over 20 kt at ksfo.

Vicinity of ksfo... Stratus retreating away from the terminal.VFR
conditions to prevail today with possible periods of MVFR
conditions due to hz from the wildfires. Stratus is expected to
return early tonight although exact timing is uncertain, later
clearing is also expected for tomorrow. West to northwest winds
this afternoon 10 to 15 kt possibly gusting to 20 kt.

Sfo bridge approach... Stratus is currently burning off and
visibility as improving. Once stratus clears expect similar
conditions to the terminal.

Monterey bay terminals... Lifr to ifr conditions currently, but
stratus is burning off. Expecting clearing shortly.VFR
conditions to prevail once stratus has cleared. Some hz or fu may
reduce vis to MVFR at times due to the wildfire in the santa cruz
mountains. Ifr CIGS due to stratus and fog are likely to return
early this evening.

Fire weather As of 3:35 am pdt Wednesday... Relative humidity
values have been increasing in the valleys and along the lower
coastal slopes as light onshore flow begins to develop. However,
the airmass in the hills above 1000 feet remains relatively warm
and very dry. Poor humidity recoveries are occurring in the hills
this morning. Fortunately, winds will remain light. More
widespread cooling will take place today as onshore winds increase
in the afternoon. This will result in better humidity recoveries
tonight into Thursday morning and more significant cooling by
Thursday. A weak early season weather system is forecast to bring
light rain to the north bay from Thursday afternoon through
Thursday evening and to much of the rest of the district on
Thursday night. The models have been trending drier with this
system. Latest forecast rainfall amounts for Thursday and Thursday
night range from a tenth to a quarter of an inch across northwest
sonoma county and northern marin county, and generally less than
a tenth of an inch in all other areas. Rainfall is expected to end
by Friday.

A warming trend will begin over the upcoming weekend as a high
pressure ridge begins to build over california. This ridge will
strengthen into early next week and result in warm and dry
conditions districtwide on Monday and Tuesday.

Marine As of 09:07 am pdt Wednesday... Areas of fog this
morning across the coastal waters and into the bays. Winds will
increase over the bays this afternoon into tonight. A cold front
will move across the waters late tomorrow bringing chances of
light rain. A moderate to long period mixed northwesterly and
southerly swell has arrived with buoys reporting periods of 17 to
18 seconds across the waters. Late Thursday into Friday a large
northwesterly swell train will move across he area. This large
swell will create hazardous conditions.

Mtr watches warnings advisories
Tday Sca... Pt pinos to pt piedras blancas 0-10 nm from 2 pm
sca... Sf bay from 2 pm
public forecast: rgass
aviation: as
marine: as
fire weather: sims
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
AAMC1 - 9414750 - Alameda, CA 9 mi48 min WSW 1.9 G 2.9 59°F 62°F1018.2 hPa
RTYC1 - 9414523 - Redwood City, CA 10 mi48 min N 4.1 G 5.1 58°F 65°F1017.3 hPa
LNDC1 11 mi48 min W 2.9 G 5.1 60°F 1017.9 hPa
OBXC1 12 mi48 min 56°F 52°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 12 mi48 min NNW 4.1 G 6
OKXC1 - 9414776 - Oakland (Berth 34), CA 13 mi48 min NW 7 G 8 55°F 1017.8 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 14 mi48 min NNE 1.9 G 2.9 55°F 1016.8 hPa
PXSC1 14 mi48 min 56°F 53°F
FTPC1 - 9414290 - San Francisco, CA 17 mi54 min WSW 5.1 G 13 53°F 57°F1018.6 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 19 mi48 min SSW 7 G 8 58°F 1018.2 hPa
RCMC1 - 9414863 - Richmond, CA 21 mi54 min S 2.9 G 4.1 57°F 59°F1017.9 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 21 mi69 min SE 8 57°F 1018 hPa
46237 - San Francisco Bar, CA (142) 24 mi66 min 56°F5 ft
MZXC1 - 9415102 - Martinez-Amorco CA 27 mi48 min WNW 7 G 8.9 64°F 63°F1017.4 hPa51°F
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 28 mi48 min NW 5.1 G 6 57°F 1017.5 hPa
PCOC1 - 9415144 - Port Chicago, CA 30 mi48 min W 6 G 7 65°F 63°F1017.1 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 32 mi48 min NW 5.1 G 7 66°F 1016.8 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 34 mi46 min WNW 5.8 G 7.8 50°F 55°F5 ft1018.6 hPa (+0.0)
SFXC1 - San Francisco Bay Reserve, CA 39 mi111 min WNW 1.9 69°F 1017 hPa45°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 40 mi46 min NNW 9.7 G 12 53°F 56°F7 ft1018.2 hPa (+0.0)
PRYC1 - 9415020 - Point Reyes, CA 47 mi48 min W 4.1 G 6 55°F1018.2 hPa

Wind History for Alameda, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Oakland, Metro Oakland International Airport, CA3 mi43 minW 37.00 miA Few Clouds61°F53°F75%1017.6 hPa
Hayward, Hayward Air Terminal, CA5 mi42 minVar 35.00 miFair with Haze63°F48°F60%1018.5 hPa
San Francisco, San Francisco International Airport, CA8 mi40 minN 59.00 miA Few Clouds62°F51°F67%1017.6 hPa
San Carlos Airport, CA8 mi40 minENE 45.00 miSmoke Haze59°F53°F82%1017.9 hPa
Palo Alto Airport, CA13 mi1.8 hrsNNE 63.00 miPartly Cloudy with Haze59°F0°F%1018.6 hPa
Mountain View, Moffett Field, CA18 mi40 minN 45.00 miSmoke64°F52°F65%1017.9 hPa
Half Moon Bay Airport, CA18 mi41 minW 67.00 miOvercast55°F50°F82%1017.9 hPa
Livermore, Livermore Municipal Airport, CA21 mi43 minVar 39.00 miSmoke76°F33°F21%1016.3 hPa

Wind History from OAK (wind in knots)
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Last 24hrSW6W6W8NW7NW8NW7W9CalmW3NW8NW5W10NW4N3N3N3NE5N3NE3CalmW43SW5W3
1 day agoW8W7NW9NW6NW9NW4CalmCalmCalmCalmNE3NE3CalmNE3CalmE3CalmNE3CalmCalmCalmS5W5W3
2 days agoW6W6NW7NW8NW4NW4CalmW3CalmW4CalmW3NE4CalmCalmCalmCalmS4SE4S4SW3W6W5W6

Tide / Current Tables for San Leandro Marina, San Francisco Bay, California
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San Leandro Marina
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Wed -- 12:00 AM PDT     6.98 feet High Tide
Wed -- 06:07 AM PDT     Moonrise
Wed -- 06:14 AM PDT     0.81 feet Low Tide
Wed -- 07:20 AM PDT     Sunrise
Wed -- 12:23 PM PDT     7.65 feet High Tide
Wed -- 06:17 PM PDT     Moonset
Wed -- 06:26 PM PDT     Sunset
Wed -- 06:50 PM PDT     0.47 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
76.65.542.51.30.81.12.13.65.26.77.67.56.65.13.31.70.70.51.12.33.95.4

Tide / Current Tables for Little Coyote Pt 3.4 mi NNE, South San Francisco Bay, California Current
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Little Coyote Pt 3.4 mi NNE
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Wed -- 02:48 AM PDT     -0.73 knots Max Ebb
Wed -- 06:02 AM PDT     0.01 knots Slack
Wed -- 06:07 AM PDT     Moonrise
Wed -- 07:20 AM PDT     Sunrise
Wed -- 09:00 AM PDT     0.72 knots Max Flood
Wed -- 11:55 AM PDT     -0.01 knots Slack
Wed -- 03:10 PM PDT     -0.82 knots Max Ebb
Wed -- 06:17 PM PDT     Moonset
Wed -- 06:26 PM PDT     Sunset
Wed -- 06:31 PM PDT     0.01 knots Slack
Wed -- 09:30 PM PDT     0.73 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
-0.1-0.5-0.7-0.7-0.6-0.4-00.40.60.70.60.4-0-0.4-0.7-0.8-0.8-0.6-0.20.20.50.70.70.5

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 (16,3,4,5)
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Ground Weather Radar Station San Francisco Bay Area, 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.