Monday, January22, 2018 L-36.com


Marine Weather and Tides
Portola Valley, 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 7:16AMSunset 5:24PM Monday January 22, 2018 6:14 PM PST (02:14 UTC) Moonrise 10:35AMMoonset 10:56PM Illumination 38% Phase: Waxing Crescent; Moon at 6 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
    EDIT      (on/off)   Help
PZZ560 Pigeon Point To Point Pinos To 10 Nm- 231 Pm Pst Mon Jan 22 2018
.small craft advisory in effect through late tonight...
Tonight..N winds 5 to 15 kt. Wind waves 1 to 3 ft. W swell 8 to 10 ft at 14 seconds.
Tue..NE winds 5 to 15 kt...becoming nw in the afternoon. Wind waves 1 to 3 ft. W swell 7 to 9 ft at 13 seconds.
Tue night..N winds 10 kt. Wind waves 2 ft or less. W swell 5 to 7 ft at 12 seconds.
Wed..S winds 10 kt. Wind waves 2 ft or less. W swell 5 to 7 ft at 12 seconds. Rain in the afternoon.
Wed night..SW winds 10 to 20 kt. Wind waves 2 to 4 ft. W swell 6 to 8 ft at 12 seconds. Rain likely in the evening, then chance of showers after midnight.
Thu..NW winds 10 to 20 kt. Wind waves 2 to 4 ft. W swell 10 to 13 ft. Chance of showers.
Fri..NW winds 10 kt. Wind waves 2 ft or less. NW swell 9 to 12 ft.
Sat..N winds 10 kt. Wind waves 2 ft or less. NW swell 6 to 8 ft.
PZZ500 231 Pm Pst Mon Jan 22 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... SWitch to northwesterly winds is progressing down the coast behind the dissipating cold front, now located along the northern big sur coast. Small craft advisories remain in place due to hazardous sea conditions caused by large swells. These swells will continue to gradually decrease through Tuesday. However, the next frontal system is set to arrive mid-week bringing back strengthening southerly winds and increasing northwest swell.

7 Day Forecast for Marine Location Near Portola Valley, CA
   Hourly   EDIT   Help
location: 37.36, -122.23     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus66 kmtr 230029
afdmtr
area forecast discussion
national weather service san francisco bay area
429 pm pst Mon jan 22 2018

Synopsis Central coast lingering showers will quickly end this
evening. Otherwise look for partly cloudy skies tonight with
patchy fog developing in the valleys. Dry and seasonably cool
weather forecast Tuesday. Next front arrives weds morning or
midday in the north bay and then spreads rain southward later weds
afternoon into weds night for the bay area into the central
coast. Steady rain quickly turns to showers before sunrise
Thursday. A round of more organized showers is possible Thursday
afternoon as the upper low moves inland. Dry weather forecast
Friday through the weekend and into early next week.

Discussion As of 2:05 pm pst Monday... Kmux radar picking up
the last few showers across the central coast as the frontal band
that passed through the area last night and this morning
dissipates. Short term concern for tonight will be some fog
development with moist boundary layer and high pressure building
in which should strengthen valley inversions.

Outside of morning fog no real weather concerns for Tuesday with
dry and seasonably cool weather forecast as high pressure briefly
builds.

Run of the mill pacific frontal passage on tap for weds. As has
been the trend of late, the models seem to be showing a less
robust frontal passage. Latest timing would bring steady frontal
rains into the north bay later weds morning or around midday.

Front will then slide southward through the bay area weds
afternoon and evening. Similar to todays front, the rain will
weaken and become more disorganized by the time it reaches the
central coast. The north bay coastal hills will be the winners
once again with 1-2 inches of rain possible while amounts will
drop off sharply over the bay area and central coast. Winds
associated with the front will be fairly light too, some gusts in
the 25-35 mph range as the front passes through.

Any steady rain will quickly turn to showers before sunrise
Thursday. Cold air aloft and an associated shortwave are forecast
to pass through on Thursday afternoon. This should produce an
organized area of rain and isolated thunderstorms, especially
focused from about the santa cruz mtns northward. Some brief heavy
rain and small hail will be possible as this feature passes
through.

Dry weather returns Thursday night into Friday. Latest model
trends show above average confidence for dry conditions Friday
through the weekend and into early next week. Some of the gfs
solutions keep the storm track just to our north but ensembles
suggest another west coast ridge could become entrenched so the
wed-thu rain may be the last significant rainfall for awhile.

Aviation As of 4:30 pm pst Monday... A weak front is now south
of the mry bay area. CIGS have started to break out except in the
mry bay area but abundant moisture remains over the area behind
the front. Therefore expect MVFR CIGS to redevelop in the sfo bay
area by around midnight. With light northeast flow expected later
tonight this could bring some fog from the inland valley into sfo
oak and the approach. Areas of dense fog is expected in the north
bay valleys while vsbys could drop as low as 1-3 miles in the sfo
bay area between 12z and 17z.

Vicinity of ksfo... MVFR CIGS expected to redevelop after 08z.

Vsbys may drop down to 1-3 miles between 12z and 17z. West winds
to 10 kts becoming light northeast after 08z.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... MVFR CIGS will be breaking up in the next
hour and there will be a brief period ofVFR. However MVFR cigs
are expected to return after 05-06z due to abundant low-level
moisture.

Marine As of 4:30 pm pst Monday... Switch to northwesterly
winds is progressing down the coast behind the dissipating cold
front, now located along the northern big sur coast. Small craft
advisories remain in place due to hazardous sea conditions caused
by large swells. These swells will continue to gradually decrease
through Tuesday. However, the next frontal system is set to arrive
mid-week bringing back strengthening southerly winds and
increasing northwest swell.

Mtr watches warnings advisories
Tngt Sca... Pt arena to pt reyes 0-10 nm
sca... Pt reyes to pigeon pt 0-10 nm
sca... Pigeon pt to pt pinos 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... Rough bar advisory for sf bar
public forecast: rww
aviation: W pi
marine: blier
visit us at

Weather Reporting Stations
   EDIT       (on/off)   Help   NOTE: Click on distance to see the station location on a map
Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
RTYC1 - 9414523 - Redwood City, CA 10 mi45 min WNW 4.1 G 6 54°F 55°F1026.3 hPa
AAMC1 - 9414750 - Alameda, CA 29 mi45 min ESE 4.1 G 6 54°F 55°F1026 hPa
LNDC1 30 mi45 min E 6 G 8.9 54°F 1025.8 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 31 mi45 min W 5.1 G 7 54°F 1024.8 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 31 mi45 min NNW 4.1 G 5.1
OBXC1 31 mi45 min 54°F 49°F
PXSC1 32 mi45 min 55°F 48°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 32 mi45 min NW 5.1 G 5.1 54°F 1025.9 hPa
FTPC1 - 9414290 - San Francisco, CA 33 mi45 min NNW 5.1 G 7 53°F 54°F1026.2 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 35 mi85 min NNW 9.7 G 14 54°F 56°F13 ft1025.9 hPa (+0.0)
46237 - San Francisco Bar, CA (142) 36 mi105 min 54°F10 ft
PPXC1 - 9414847 - Richmond (Point Potrero), CA 38 mi51 min ENE 4.1 G 8.9 53°F 1026.2 hPa
TIBC1 - Tiburon Pier, San Francisco Bay, CA 39 mi51 min NE 4.1 52°F 1026 hPa
RCMC1 - 9414863 - Richmond, CA 40 mi45 min ENE 7 G 8.9 52°F 54°F1025.7 hPa
46042 - MONTEREY - 27NM West of Monterey Bay, CA 41 mi85 min NW 12 G 14 56°F 56°F13 ft1025.8 hPa (+0.3)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 42 mi85 min NW 9.7 G 14 54°F 55°F10 ft1026 hPa (+0.0)
46092 - MBM1 43 mi60 min WNW 14 56°F 56°F1025.7 hPa (+0.3)
46114 - West Monterey Bay, CA 44 mi45 min 55°F12 ft
ELXC1 - Elkhorn Slough Reserve, CA 46 mi150 min N 4.1 57°F 1026 hPa54°F
MZXC1 - 9415102 - Martinez-Amorco CA 47 mi45 min ENE 4.1 G 5.1 51°F 52°F1026.8 hPa51°F
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 48 mi45 min E 12 G 16 51°F 1026 hPa
PCOC1 - 9415144 - Port Chicago, CA 49 mi45 min NE 8 G 9.9 50°F 52°F1026.6 hPa

Wind History for Redwood City, CA
(wind in knots)    EDIT      (on/off)   Help
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
Last
24hr
S3
S5
SE5
SE5
G8
SE4
G8
SE4
E5
SE3
SE5
G10
SE5
G8
SE5
G8
SE4
G8
SE5
G9
SE6
G9
SE7
N2
E2
E1
NW7
G10
W8
NW11
W9
W10
NW5
1 day
ago
SW6
W7
W6
W4
S1
SE1
S1
SE4
SE1
SE3
S3
SE2
W2
SE3
SE2
SE4
E2
E4
E5
G8
NE2
G6
E3
E2
E3
SW3
2 days
ago
W6
W6
W8
W5
W4
W6
W4
W5
NW5
NW4
W5
W2
NW6
NW2
SE2
SE2
NE2
N3
G6
N3
G6
N5
G8
NW6
NW7
G11
NW10
W8
G11

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Palo Alto Airport, CA10 mi28 minWNW 810.00 miMostly Cloudy50°F44°F82%1025.7 hPa
Mountain View, Moffett Field, CA11 mi79 minNNW 610.00 miOvercast55°F44°F67%1026.5 hPa
San Carlos Airport, CA12 mi22 minW 410.00 miMostly Cloudy54°F44°F72%1025.7 hPa
San Jose, San Jose International Airport, CA16 mi22 minWNW 610.00 miMostly Cloudy53°F44°F72%1025.6 hPa
Half Moon Bay Airport, CA18 mi20 minNNE 54.00 miFog/Mist48°F44°F87%1025.1 hPa
San Francisco, San Francisco International Airport, CA19 mi79 minW 1110.00 miA Few Clouds54°F44°F69%1025.9 hPa
San Jose / Reid / Hillv, CA22 mi25 minN 010.00 miMostly Cloudy54°F42°F67%1025.1 hPa
Hayward, Hayward Air Terminal, CA22 mi21 minN 310.00 miPartly Cloudy53°F44°F72%1026.7 hPa
Oakland, Metro Oakland International Airport, CA23 mi22 minNNE 610.00 miPartly Cloudy50°F46°F86%1025.9 hPa

Wind History from PAO (wind in knots)
7
PM
8
PM
9
PM
10
PM
11
PM
12
AM
1
AM
2
AM
3
AM
4
AM
5
AM
6
AM
7
AM
8
AM
9
AM
10
AM
11
AM
12
PM
1
PM
2
PM
3
PM
4
PM
5
PM
6
PM
Last 24hrCalmCalmCalm------------------SE7SE10SE9W105--NE5NW12NW10NW12NW8NW8
1 day agoW8W6Calm------------------Calm--5SE6----NE55455--
2 days agoW7W7W8--------------------------N6--5N8--NW10----

Tide / Current Tables for Granite Rock, Redwood Creek, San Francisco Bay, California
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Granite Rock
Click for Map
Mon -- 04:13 AM PST     7.44 feet High Tide
Mon -- 07:19 AM PST     Sunrise
Mon -- 10:21 AM PST     2.54 feet Low Tide
Mon -- 10:35 AM PST     Moonrise
Mon -- 03:35 PM PST     6.66 feet High Tide
Mon -- 05:22 PM PST     Sunset
Mon -- 10:23 PM PST     0.86 feet Low Tide
Mon -- 10:56 PM PST     Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
2.445.66.87.47.26.45.2432.62.73.54.65.76.56.66.15.23.92.51.50.91

Tide / Current Tables for Dumbarton Hwy Bridge, South San Francisco Bay, California Current
   EDIT      (on/off)   Help   One Week of Data
Dumbarton Hwy Bridge
Click for Map
Mon -- 01:45 AM PST     1.50 knots Max Flood
Mon -- 04:59 AM PST     -0.00 knots Slack
Mon -- 07:18 AM PST     Sunrise
Mon -- 08:02 AM PST     -0.84 knots Max Ebb
Mon -- 10:34 AM PST     Moonrise
Mon -- 11:03 AM PST     0.00 knots Slack
Mon -- 01:58 PM PST     0.99 knots Max Flood
Mon -- 04:35 PM PST     -0.00 knots Slack
Mon -- 05:21 PM PST     Sunset
Mon -- 08:13 PM PST     -0.99 knots Max Ebb
Mon -- 10:56 PM PST     Moonset
Mon -- 11:06 PM PST     0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
11.41.51.20.7-0-0.4-0.7-0.8-0.7-0.3-00.40.810.80.3-0.1-0.5-0.8-1-0.9-0.5-0

Weather Map and Satellite Images
       (on/off)   Help
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 (21,6,7,8)
      (on/off)   Help

Ground Weather Radar Station San Francisco Bay Area, CA
   (on/off)   Help
weather_mapweather_map weather_map

Ad by Google

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.