Tuesday, July14, 2020
Privacy Policy
L-36.com


Marine Weather and Tides
Portola Valley, CA

Version 3.4
NOTICE
12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed.
10/9/2019 Updated the Marine Zones.
9/4/2019 Fixed the weather maps due to NOAA moving them.
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.

Sunrise 5:58AMSunset 8:30PM Tuesday July 14, 2020 2:58 PM PDT (21:58 UTC) Moonrise 12:33AMMoonset 2:06PM Illumination 30% Phase: Waning Crescent; Moon at 24 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 Coastal Waters From Pigeon Point To Point Pinos California Out To 10 Nm- 857 Am Pdt Tue Jul 14 2020
Today..SW winds up to 10 kt. Wind waves 1 to 2 ft. NW swell 4 to 6 ft at 9 seconds and S around 2 ft at 10 seconds.
Tonight..S winds 5 to 10 kt. Wind waves 1 ft. NW swell 3 to 5 ft at 9 seconds and S around 2 ft at 10 seconds.
Wed..S winds 5 to 15 kt. Wind waves 1 to 2 ft. NW swell 3 to 5 ft at 9 seconds.
Wed night..S winds up to 10 kt. Wind waves 1 ft. NW swell 4 to 5 ft at 10 seconds.
Thu..S winds 5 to 10 kt. Wind waves 1 ft. NW swell 4 to 5 ft at 10 seconds.
Thu night..SW winds 5 to 10 kt. Wind waves 1 ft. NW swell 4 to 5 ft at 10 seconds.
Fri..W winds up to 10 kt. Wind waves 1 ft. NW swell 3 to 5 ft.
Sat..SW winds up to 10 kt. Wind waves 1 ft. NW swell 4 to 5 ft.
PZZ500 857 Am Pdt Tue Jul 14 2020
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... A weak surface low off the san mateo coast is resulting in split flow with light southerly winds along the immediate coastline and stronger northwest winds in the outer waters. Winds will increase over the northern san francisco bay during the afternoon and evening hours. This pattern is expected to continue through Thursday.


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 142106 AFDMTR

Area Forecast Discussion National Weather Service San Francisco Bay Area 206 PM PDT Tue Jul 14 2020

SYNOPSIS. A few additional degrees of inland cooling is expected on Tuesday as onshore flow increases. Temperatures will then likely remain near seasonal averages for the remainder of the week and into the upcoming weekend along with the ebb and flow of overnight and morning low clouds.

DISCUSSION. as of 02:05 PM PDT Tuesday . Feels more like "summer" this afternoon as low clouds hug the coast and sunshine blankets the interior. Temperatures on the other hand are several degrees below seasonal averages for late July. Highs will top out in the upper 70s to lower 90s away from the coast, but much cooler at the coast with upper 50s to 60s. Latest 24 hour trend shows many of these temperatures will fall with in a few degrees of Monday's values.

For tonight - marine layer will make its nightly march inland, possibly covering a few more interior valleys than this morning. Fire weather concerns will still lingering above the marine layer, especially the higher peaks with mild temperatures, poor humidity recoveries, and crispy fine fuels.

Wednesday will feature another day of morning low clouds retreating to the coast with inland sunshine. Only minor differences in the temperatures with highs on Wednesday with below seasonal averages.

One thing to keep an eye on Wednesday/Thursday will be a developing upper low off the SoCal coast as high pressure remains well to the east. This orientation will allow for some monsoonal moisture to sneak up the Sierra Crest through out these two days. Neighboring offices to the east have a mention for afternoon thunderstorms over the Crest on Wednesday. More moisture and more widespread chances for thunderstorms develop Thursday afternoon over the Sierra Nevada. So what does these mean locally? No chance for thunderstorms at this point, but a few models bring some upper level instability/moisture to the North and East Bay. The net result will be a slight uptick in overnight humidity recoveries and possible afternoon cu.

Upper level high pressure begins to nose westward Friday and over the weekend. The building 500mb heights will likely compress the marine layer a tad, but not completely squash it. The building high pressure will also lead to a slight warming trend across the interior.

AVIATION. as of 11:00 AM PDT Tuesday . A surface eddy between the Farallon Islands and Point Reyes is resulting in a weak south to southwest feed along the coast. This resulted in an unusual stratus pattern early this morning but as of late this morning it looks more familiar with stratus along the coast with a thicker layer in and around the Monterey Bay. As such, widespread VFR except at Monterey Bay terminals. Breezy to locally gusty onshore (W-SW) winds today near coastal gaps. For tonight, expecting a similar stratus intrusion except with more of a push into the North Bay to include KSTS and slightly more compressed (lower cigs) into the night. KSFO/KOAK will be on the boundary overnight but expecting predominately VFR at KSFO with borderline MVFR/IFR at KOAK. KSJC/KLVK should remain clear through the period.

Vicinity of KSFO . VFR today. Breezy onshore winds. Stratus should remain just north of KSFO again tonight with WSW flow though KOAK will likely be under OVC being just that more northward than KSFO.

SFO Bridge Approach . Similar to KSFO except in an even drier slot with less chance of low clouds overnight tonight.

Monterey Bay Terminals . Marine layer is eroding northward from the Salinas Valley late this morning and may lift away from KMRY midday however intermittent SCT/BKN is expected thru midday as WSW reinforced marine layer into the vicinity. KWVI/Santa Cruz under OVC all day given deep offshore reinforcing component and flow direction. Breezy to infrequently onshore winds this afternoon. IFR cigs return tonight for KSNS/KMRY.

MARINE. as of 10:51 AM PDT Tuesday . A weak surface low off the San Mateo coast is resulting in split flow with light southerly winds along the immediate coastline and stronger northwest winds in the outer waters. Winds will increase over the northern San Francisco Bay during the afternoon and evening hours. This pattern is expected to continue through Thursday.

MTR WATCHES/WARNINGS/ADVISORIES. Tngt. SCA . Pt Arena to Pigeon Pt 10-60 nm until 6 PM SCA . SF Bay until 9 PM



PUBLIC FORECAST: MM AVIATION: DRP MARINE: DRP

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/nwsbayarea www.twitter.com/nwsbayarea www.youtube.com/nwsbayarea


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 mi58 min 75°F
AAMC1 - 9414750 - Alameda, CA 29 mi58 min 69°F
FTPC1 - 9414290 - San Francisco, CA 33 mi58 min 63°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 35 mi38 min SSW 5.8 G 7.8 55°F 1015.3 hPa53°F
46237 - San Francisco Bar, CA (142) 36 mi58 min 56°F4 ft
TIBC1 - Tiburon Pier, San Francisco Bay, CA 39 mi54 min SSW 11 60°F 1013 hPa
RCMC1 - 9414863 - Richmond, CA 40 mi58 min 65°F
46042 - MONTEREY - 27NM West of Monterey Bay, CA 41 mi38 min S 3.9 G 5.8 56°F 56°F1015.9 hPa55°F
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 42 mi38 min S 9.7 G 14 54°F 55°F1014.9 hPa53°F
46092 - MBM1 43 mi39 min SSW 9.7 56°F 55°F1015.5 hPa (+0.0)
MLSC1 - Moss Landing, South Harbor, CA 45 mi100 min W 8 G 21 1015 hPa
46114 - West Monterey Bay, CA 46 mi32 min 54°F6 ft
ELXC1 - Elkhorn Slough Reserve, CA 46 mi73 min WNW 8 62°F 56°F
MZXC1 - 9415102 - Martinez-Amorco CA 47 mi58 min 72°F
PCOC1 - 9415144 - Port Chicago, CA 49 mi58 min 72°F

Wind History for Redwood City, CA
(wind in knots)    EDIT      (on/off)   Help
3
PM
4
PM
5
PM
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
Last
24hr
NW11
G15
W11
G14
W14
G17
NW14
NW11
NW9
NW4
SW3
S5
G8
S4
G8
S4
W3
NW2
NW3
--
S3
SE1
W1
NW3
N4
G7
N6
N5
N8
G11
NW11
1 day
ago
N11
G17
W11
G15
W14
W12
W11
G14
W11
W8
W6
W11
NW7
N4
S2
W4
W3
W4
W9
NW5
W1
NW5
NW9
G12
N11
G14
N9
G13
N12
NW11
G14
2 days
ago
NW12
N12
NW11
NW12
NW7
W10
NW9
G12
NW7
NW4
NW3
NW4
NW3
NW3
NW1
NW3
NW2
NW3
--
NW2
N6
N2
G5
N6
N6
G9
N8
G11

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Palo Alto Airport, CA10 mi71 minN 1110.00 miClear73°F55°F53%1013.2 hPa
San Carlos Airport, CA12 mi71 minW 1010.00 miClear72°F53°F53%1013.5 hPa
San Jose, San Jose International Airport, CA16 mi65 minVar 510.00 miFair80°F51°F37%1012.3 hPa
San Francisco, San Francisco International Airport, CA19 mi62 minS 710.00 miFair70°F55°F59%1013.3 hPa
Hayward, Hayward Air Terminal, CA22 mi64 minW 910.00 miFair74°F53°F48%1013.9 hPa
San Jose / Reid / Hillv, CA22 mi2.2 hrsSSW 710.00 miClear77°F53°F44%1013.2 hPa
Oakland, Metro Oakland International Airport, CA23 mi65 minW 810.00 miA Few Clouds73°F55°F53%1013.4 hPa

Link to 5 minute data for KPAO

Wind History from PAO (wind in knots)
3
PM
4
PM
5
PM
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
Last 24hrN17N14
G21
------------------------------SE4--E4E7N7N8N11
1 day agoN15--N15----------------------------CalmN4N8N10N13N14NW17
2 days agoN15N13N15------------------------------N6N6N6N6NW8NW11

Tide / Current Tables for Granite Rock, Redwood Creek, San Francisco Bay, California
   EDIT   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Granite Rock
Click for Map
Tue -- 01:32 AM PDT     Moonrise
Tue -- 03:30 AM PDT     1.52 feet Low Tide
Tue -- 05:59 AM PDT     Sunrise
Tue -- 09:05 AM PDT     5.05 feet High Tide
Tue -- 02:33 PM PDT     2.32 feet Low Tide
Tue -- 03:06 PM PDT     Moonset
Tue -- 08:29 PM PDT     Sunset
Tue -- 08:36 PM PDT     7.95 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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
7
pm
8
pm
9
pm
10
pm
11
pm
4.22.921.61.62.23.144.85.14.94.43.62.92.42.434.25.677.87.97.46.4

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
Tue -- 12:00 AM PDT     -0.84 knots Max Ebb
Tue -- 01:32 AM PDT     Moonrise
Tue -- 03:54 AM PDT     0.00 knots Slack
Tue -- 05:59 AM PDT     Sunrise
Tue -- 06:55 AM PDT     0.90 knots Max Flood
Tue -- 09:39 AM PDT     -0.00 knots Slack
Tue -- 12:18 PM PDT     -0.49 knots Max Ebb
Tue -- 03:06 PM PDT     Moonset
Tue -- 03:25 PM PDT     0.00 knots Slack
Tue -- 06:33 PM PDT     0.98 knots Max Flood
Tue -- 08:29 PM PDT     Sunset
Tue -- 09:24 PM PDT     -0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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
7
pm
8
pm
9
pm
10
pm
11
pm
-0.8-0.8-0.6-0.30.10.50.80.90.80.4-0.1-0.4-0.5-0.4-0.3-0.10.20.70.910.70.3-0.2-0.6

Weather Map
       (on/off)   Help Weather Map
wmap_P
GEOS Local Image of CentralWestCoast    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East
Wind Forecast for San Francisco/Monterey Bay Area, CA (17,4,5,8)
      (on/off)   Help

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

Ad by Google

Cookie Policy:
This website uses cookies to save your settings. No personal information is saved. I do not collect statistics on your visit. You can disable cookies in your browser if you like but it is not recommended for this site. I do not sell cookies. Go to a bakery for that. In fact I do not sell anything. To disable cookies from L-36.com, please refer to the Help button in your browser.
Privacy Policy:
I do not sell or share any user data or anything else for that matter. The only personal information I save is in the site log which has a line for each page view which includes the IP address your browser sends in the header as well as which page you requested. I use this to block hackers and other bad actors. I do not use this raw data to create profiles on users. I periodically delete the log files. If you are subject to CCPA, Google ads on this site will not be based on your past behavior so you will likely not see an ad for a lawn mower just because you looked for one at a big box website. I do not believe this site is subject to CCPA but I am doing what I can to follow the guidelines anyway.
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 numerous 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.