Sunday, April30, 2017 L-36.com


Marine Weather and Tides
Colma, CA

Version 3.4
What's New / NOTES
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.
3/12/2015 - Added section for Gulf current for users in the GMZ marine zones.
This was requested by a user. If you have requests, please let me know.

Sunrise 6:12AMSunset 8:01PM Sunday April 30, 2017 9:54 AM PDT (16:54 UTC) Moonrise 9:12AMMoonset 11:49PM Illumination 22% Phase: Waxing Crescent; Moon at 5 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- 826 Am Pdt Sun Apr 30 2017
Today..SW winds 5 kt...increasing to 5 to 15 kt in the afternoon.
Tonight..W winds 5 to 15 kt.
Mon..NW winds 5 to 15 kt.
Mon night..W winds 5 to 15 kt.
Tue..W winds 5 to 15 kt.
Wed..W winds 10 kt.
Thu..SW winds 10 kt.
PZZ500 826 Am Pdt Sun Apr 30 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... High pressure will continue to generate strong northwest winds across the coastal waters today and through most of the forecast period. Winds may subside slightly by Thursday. In addition...the strong winds will also continue to cause very rough seas due to fresh swells with short periods.

7 Day Forecast for Marine Location Near Colma, CA
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location: 37.68, -122.42     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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Fxus66 kmtr 301521
afdmtr
area forecast discussion
national weather service san francisco bay area
821 am pdt Sun apr 30 2017

Synopsis Sunny and seasonably warm weather will continue across
our region today with temperatures similar to those of yesterday.

Warming is then forecast from Monday through Wednesday as
offshore flow develops and high pressure strengthens over
california. Widespread 80s are forecast by Tuesday and Wednesday,
with some lower to mid 90s in the warmest inland areas. A cooling
trend is then forecast Thursday and Friday as the upper ridge over
california is replaced by a trough. Rain showers are possible
next weekend when an upper low is forecast to develop over
california.

Discussion As of 8:10 am pdt Sunday... Sunny skies across our
entire region with the exception of a small patch of clouds
around monterey bay. A ridge of high pressure building into our
cwa along with an offshore flow at the surface will lead to
several warm days for both the coast and inland spots. Highs today
will be in the 60s to mid 70s at the coast with mid 70s to mid
80s inland. Additional warming is likely for Monday through
Wednesday as the ridge strengthens and moves to california.

Offshore winds will also be on the increase tonight and Monday
night especially for higher elevation spots.

Current forecast appears to be on track. No major updates planned.

Previous discussion The light offshore flow that was in place
across our region early yesterday morning has been replaced by
light onshore flow. As a result, current surface dewpoints are as
much as 15 degrees f above what they were at the same time early
yesterday morning, and patchy light fog is currently being
reported at half moon bay and watsonville. However, the boundary
layer has probably not moistened enough for widespread development
of coastal low clouds/fog. Thus, sunny conditions are expected
across our forecast area once again today. However, our warming
trend will be suspended for today as increased moisture in the low
levels will offset continued airmass warming aloft. The net
effect will probably be slightly cooler high temperatures near the
coast today, and temperatures near persistence inland.

Offshore flow is forecast to redevelop tonight as surface high
pressure builds inland to our north and east. In fact, locally
gusty north winds are expected to develop in the hills by late
tonight and Monday morning, and then again late Monday night and
Tuesday morning. Wind gusts in the hills may reach 30-35 mph in
isolated locations during the night and morning hours. This
offshore flow will result in renewed drying of the airmass across
our region. At the same time, the upper ridge that is currently
centered offshore is forecast to shift eastward and over
california, resulting in and increase of 850 mb temperatures
from about 12 degrees c currently to about 19 or even 20 deg c by
Wednesday. These developments will result in a resumption of the
warming trend on Monday, with warming continuing regionwide into
Tuesday and on into Wednesday in many areas. The warmest days of
the week are expected to be Tuesday and Wednesday when widespread
80s are forecast, with low to mid 90s likely in the warmer inland
areas. Even coastal areas will probably see highs up around 80
due to offshore flow. High temperatures will be as much as 15
degrees warmer than normal on Tuesday and Wednesday, and these
two days are likely to be the warmest days our region has seen
since last october.

Significant cooling is forecast for Thursday and Friday as the
upper ridge moves off to our east and an upper trough develops
near the west coast. Expect temperatures to cool by at least 10
degrees on Thursday and drop back down to around seasonal averages
by Thursday. Low clouds and fog will likely develop in coastal
areas by Thursday.

The longer range models indicate an upper low will drop south
along or near the west coast next weekend, producing a chance of
showers across our forecast area. The 00z ECMWF is especially
bullish with precip chances showing widespread rainfall across our
area by next Sunday.

Aviation As of 04:22 am pdt Sunday... For 12z tafs. Another day
ofVFR in store at all terminals. High pressure will continue to
dominate over the region, with perhaps only a few high clouds
through the day. Winds should remain light-moderate, occasionally
gusty, from the west/northwest this afternoon. By late tonight,
guidance suggests some low level moisture returning, especially
for monterey bay terminals. The extend and coverage is still
unknown at this time. With high pressure in control, did not see
enough reason to include CIGS in the 12z TAF update. Moderate to
high confidence.

Vicinity of ksfo...VFR. Light to moderate onshore winds this
afternoon and evening, gusty at times.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR. Mainly light to moderate onshore winds
this afternoon, should stay below 15 kt. Did include few-sct low
clouds by 08z, with the possibility of MVFR/ifr CIGS before
sunrise Monday. However, confidence is low at this time.

Marine As of 04:05 am pdt Sunday... High pressure will continue
to generate strong northwest winds today and through the majority
of the forecast period for the coastal waters. Winds may subside
slightly by Thursday. In addition, the strong winds will also
continue to cause very rough seas due to fresh swells with short
periods.

Mtr watches/warnings/advisories
Tday Sca... Pigeon pt to pt pinos 0-10 nm from 3 pm
sca... Pt arena to pt reyes 0-10 nm
sca... Pt reyes to pigeon pt 0-10 nm
sca... Pt pinos to pt piedras blancas 0-10 nm
sca... Pt arena to pigeon pt 10-60 nm
sca... Pigeon pt to pt piedras blancas 10-60 nm
sca... Mry bay from 3 pm
public forecast: bell/dykema
aviation: bam
marine: bam
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Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
PXOC1 - 9414311 - San Francisco (Pier 1), CA 8 mi54 min E 1.9 G 2.9 57°F 1020.2 hPa
FTPC1 - 9414290 - San Francisco, CA 9 mi54 min NW 5.1 G 5.1 55°F 55°F1021.5 hPa (+1.1)
PXSC1 9 mi54 min 58°F 52°F
AAMC1 - 9414750 - Alameda, CA 9 mi54 min Calm G 2.9 59°F 63°F1021.5 hPa (+1.1)
OBXC1 10 mi54 min 57°F 51°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 10 mi54 min NW 1.9 G 2.9 57°F 1021.2 hPa (+1.1)
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 10 mi54 min W 2.9 G 2.9
LNDC1 11 mi54 min Calm G 1 60°F 1021 hPa
46237 - San Francisco Bar, CA (142) 14 mi54 min 53°F6 ft
TIBC1 - Tiburon Pier, San Francisco Bay, CA 15 mi62 min ESE 1 58°F 1021 hPa (+1.0)
RTYC1 - 9414523 - Redwood City, CA 16 mi54 min NE 1.9 G 2.9 60°F 64°F1020.4 hPa (+0.9)
PPXC1 - 9414847 - Richmond (Point Potrero), CA 16 mi54 min Calm G 1.9 62°F 1021.5 hPa (+1.2)
RCMC1 - 9414863 - Richmond, CA 17 mi54 min S 1.9 G 2.9 58°F 58°F1021 hPa (+1.2)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 23 mi64 min NNW 9.7 G 12 51°F 51°F7 ft1021.4 hPa (+1.3)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 27 mi54 min NW 1.9 G 2.9 62°F 1021.1 hPa (+1.4)
MZXC1 - 9415102 - Martinez-Amorco CA 29 mi54 min W 4.1 G 5.1 60°F 61°F1021.4 hPa (+1.3)51°F
UPBC1 29 mi54 min WNW 2.9 G 4.1
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 33 mi64 min NNW 14 G 18 53°F 52°F8 ft1020.9 hPa (+0.3)
PCOC1 - 9415144 - Port Chicago, CA 33 mi54 min W 2.9 G 4.1 61°F 60°F1021 hPa (+1.5)
PRYC1 - 9415020 - Point Reyes, CA 37 mi54 min WNW 14 G 17 54°F 52°F1021.1 hPa (+1.5)
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 38 mi54 min N 8 G 9.9 60°F 1020.9 hPa (+1.5)
SFXC1 - San Francisco Bay Reserve, CA 42 mi69 min NW 1 62°F 1021 hPa51°F

Wind History for Alameda, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
San Francisco, San Francisco International Airport, CA5 mi58 minNNE 310.00 miFair59°F46°F64%1021 hPa
Oakland, Metro Oakland International Airport, CA11 mi61 minSW 410.00 miFair61°F51°F70%1021.2 hPa
Half Moon Bay Airport, CA12 mi59 minWNW 34.00 miFair with Haze54°F48°F82%1021.3 hPa
San Carlos Airport, CA14 mi2.1 hrsN 010.00 miClear57°F48°F72%1021 hPa
Hayward, Hayward Air Terminal, CA16 mi60 minno data10.00 miFair62°F46°F58%1021.7 hPa
Palo Alto Airport, CA21 mi3.1 hrsN 010.00 miClear50°F48°F94%1020.3 hPa

Wind History from SFO (wind in knots)
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Last 24hrNW13N10N12N9W13W16W18W16W18W20W17W17
G24
W13W11W10W11W10NW11W6W6W6W3CalmN3
1 day agoW12W10W14W14W20W20W20W23W21W19
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W18W15W14W9W8NW14N11N9NE4CalmN10N12N8N7
2 days agoN4W9W18W15W18W19
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Tide / Current Tables for South San Francisco, San Francisco Bay, California
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South San Francisco
Click for Map
Sun -- 03:18 AM PDT     7.26 feet High Tide
Sun -- 06:14 AM PDT     Sunrise
Sun -- 10:12 AM PDT     Moonrise
Sun -- 10:20 AM PDT     -1.09 feet Low Tide
Sun -- 05:25 PM PDT     5.96 feet High Tide
Sun -- 07:59 PM PDT     Sunset
Sun -- 10:32 PM PDT     2.45 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
4.15.46.67.27.16.24.72.80.9-0.4-1-0.9-0.11.22.64.15.35.95.85.24.13.12.52.5

Tide / Current Tables for Sierra Point 1.3 mi ENE, South San Francisco Bay, California Current
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Sierra Point 1.3 mi ENE
Click for Map
Sun -- 12:46 AM PDT     0.82 knots Max Flood
Sun -- 03:37 AM PDT     -0.00 knots Slack
Sun -- 06:14 AM PDT     Sunrise
Sun -- 07:17 AM PDT     -1.50 knots Max Ebb
Sun -- 10:12 AM PDT     Moonrise
Sun -- 10:42 AM PDT     0.01 knots Slack
Sun -- 01:57 PM PDT     1.14 knots Max Flood
Sun -- 05:34 PM PDT     -0.00 knots Slack
Sun -- 07:59 PM PDT     Sunset
Sun -- 08:01 PM PDT     -0.70 knots Max Ebb
Sun -- 10:51 PM PDT     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
0.70.80.60.3-0.2-0.7-1.2-1.5-1.4-1-0.40.20.711.110.70.3-0.2-0.6-0.7-0.6-0.30

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 (12,3,4,5)
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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.