Sunday, July12, 2020
Privacy Policy
L-36.com


Marine Weather and Tides
Half Moon Bay, 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 5:57AMSunset 8:33PM Sunday July 12, 2020 4:27 PM PDT (23:27 UTC) Moonrise 12:00AMMoonset 12:13PM Illumination 50% Phase: Third Quarter Moon; Moon at 22 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
PZZ531 San Francisco Bay South Of The Bay Bridge- 241 Pm Pdt Sun Jul 12 2020
Rest of today..W winds 5 to 15 kt.
Tonight..SW winds 5 to 15 kt.
Mon..W winds 10 to 20 kt with gusts up to 25 kt.
Mon night..W winds 5 to 15 kt.
Tue..NW winds 5 to 15 kt.
Tue night..NW winds 5 to 15 kt.
Wed..W winds 10 to 20 kt with gusts up to 25 kt.
Thu..SW winds 5 to 15 kt.
PZZ500 241 Pm Pdt Sun Jul 12 2020
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... A strong notherly gradient will result in moderate to locally gusty north to northwest winds across the coastal waters today and tomorrow. These winds will generate steep fresh swell resulting in hazardous conditions for small craft vessels. Winds weaken significantly and shift southward along the coast through midweek. A longer period south swell will mix with the steep fresh northwest swell.


7 Day Forecast for Marine Location Near Half Moon Bay, CA
   Hourly   EDIT   Help
location: 37.47, -122.48     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
FXUS66 KMTR 122102 AFDMTR

Area Forecast Discussion National Weather Service San Francisco Bay Area 202 PM PDT Sun Jul 12 2020

SYNOPSIS. Hot and dry conditions will persist across the interior today while cooler temperatures are expected near the coast. Interior cooling is then likely early in the week as onshore flow increases and high pressure weakens.

DISCUSSION . as of 02:02 PM PDT Sunday . Fog/low-cloud deck along the coast has all but dissipated this afternoon, with the nearest cloud deck well over 100 nautical miles off the San Francisco Peninsula. Onshore winds also remain weak across the entire CWA, but are expected to pick up somewhat over the San Francisco Penninsula and high-terrain locations in the East and South Bay later this afternoon.

Several interior locations are reporting mid-90s and low 100s; mid-to-upper 90s have been reported around Lake Berryessa while Livermore AP is currently 2 degrees short of the 100 F mark. The stations with the highest observed temperatures in our CWA at this time are down in southern Monterey County, with 101 being reported in Pinnacles National Park and 102 at Ft. Hunter Liggett. Mild temps along the coast will persist throguhout the day.

One of this afternoon's primary concerns will be the heat over the interior. The 596dm 500mb upper-level ridge that has been sitting over the southwest, where places like Phoenix and Palm Springs are well over the 110-degree F mark. The good news is we will not be reaching those excessive heat conditions over in our CWA. Nevertheless, max temps across interior Santa Clara, Napa, Sonoma, and San Benito counties are set to easily reach max temps in the mid-to-upper 90s today, while our hottest conditions today will be found in northern Napa and southern Monterey counties. Those who plan to take part in recreational activities in places like Bothe-Napa Valley State Park to our north and Pinnacles National Park to our south this afternoon should be mindful of these conditions.

In terms of fire weather, we have not observed any fires in our CWA like what was observed yesterday east of San Jose but hot temps and single- digit/low-teen RH values are something to be mindful of for the rest of the day. Thankfully, weak onshore flow has been observed throughout this entire upper-level ridge setup, which has helped to mitigate those concerns.

The axis of the 558dm 500mb upper-level trough centered over central British Columbia will gradually make its way into our CWA overnight and into Monday morning as the ridge weakens and loses its influence over the region. The marine layer also looks poised to make a comeback, with model guidance also suggesting some surface /near-surface cyclonic flow to gradually develop as a result. The big take-away is that next week's setup will lead to cooling all along the coast and especially in the interior.

AVIATION. as of 10:40 AM PDT Sunday . for 18z TAFs. Widespread VFR through the daylight hours today with a robust northerly gradient offshore and high pressure overhead suppressing the marine layer. Onshore gradient strengthens into the afternoon with warming inland allowing for breezy to locally gusty (strongest through coastal gaps) onshore winds to prevail this afternoon and evening. Marine layer anticipated to redevelop into the evening offshore before attempting to intrude inland overnight. Intrusion will not be deep but will bring borderline MVFR/IFR cigs to the coastally influenced TAF sites through the predawn to early morning hours. Breezy onshore winds redevelop tomorrow afternoon.

Vicinity of KSFO . VFR, west to northwest wind near 10 knots then increasing to 20 to near 30 knots in the afternoon to mid evening. A stratus intrusion is probable tonight and Monday morning then low to moderate forecast confidence OVC IFR ceiling until 17z-18z.

SFO Bridge Approach . Similar to KSFO.

Monterey Bay Terminals . VFR today. West winds increasing to 10 to 15 knots in the afternoon and early evening. West to northwest winds in the evening resulting in IFR ceilings developing late to overnight.

MARINE. as of 10:32 AM PDT Sunday . Robust northerly gradient will bring moderate to locally gusty northwest winds across the coastal waters today and tomorrow. Northwest winds will generate steep fresh swell resulting in hazardous conditions for small craft vessels. A longer period south swell will mix with the steep fresh northwest swell. A nearly stationary and mainly dry low pressure trough will develop over the coastal waters Tuesday through Thursday resulting in southerly winds mainly over the inner and southern coastal waters.

MTR WATCHES/WARNINGS/ADVISORIES. Tngt. SCA . Pt Reyes to Pigeon Pt 0-10 nm SCA . Pigeon Pt to Pt Pinos 0-10 nm SCA . Pt Arena to Pt Reyes 0-10 nm SCA . Pt Arena to Pigeon Pt 10-60 nm SCA . Pt Pinos to Pt Piedras Blancas 0-10 nm SCA . Pigeon Pt to Pt Piedras Blancas 10-60 nm



PUBLIC FORECAST: Diaz/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 14 mi57 min N 8.9 G 13 80°F 76°F1011.4 hPa
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 23 mi37 min NW 16 G 18 57°F 7 ft1014.1 hPa54°F
46237 - San Francisco Bar, CA (142) 23 mi57 min 61°F4 ft
AAMC1 - 9414750 - Alameda, CA 23 mi57 min W 9.9 G 11 69°F 71°F1012 hPa
PXSC1 23 mi57 min 68°F 53°F
FTPC1 - 9414290 - San Francisco, CA 23 mi57 min WSW 17 G 24 61°F 65°F1012 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 23 mi57 min WSW 5.1 G 8.9 70°F 1010.8 hPa
OBXC1 24 mi57 min 68°F 53°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 24 mi57 min W 5.1 G 5.1
OKXC1 - 9414776 - Oakland (Berth 34), CA 25 mi57 min W 8 G 9.9 68°F 1011.8 hPa
LNDC1 25 mi57 min WSW 8 G 9.9 74°F 1011.6 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 27 mi37 min WNW 18 G 21 55°F 55°F5 ft1013 hPa53°F
TIBC1 - Tiburon Pier, San Francisco Bay, CA 29 mi47 min SSE 5.1 76°F 1011 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 31 mi57 min SSW 13 G 17 64°F 1011.8 hPa
RCMC1 - 9414863 - Richmond, CA 32 mi57 min S 8 G 12 69°F 67°F1011 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 42 mi57 min WSW 12 G 14 81°F 1009.9 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 43 mi57 min WNW 13 G 15 89°F 73°F1009.7 hPa
UPBC1 44 mi57 min WNW 8.9 G 14
PCOC1 - 9415144 - Port Chicago, CA 47 mi57 min W 14 G 16 87°F 73°F1009.3 hPa
46042 - MONTEREY - 27NM West of Monterey Bay, CA 48 mi37 min NW 19 G 25 57°F 56°F7 ft1012.9 hPa54°F

Wind History for Redwood City, CA
(wind in knots)    EDIT      (on/off)   Help
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
3
PM
Last
24hr
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
N11
G17
1 day
ago
NW11
G14
NW12
NW11
NW10
NW9
N6
G9
NW4
NW5
NW4
NW4
NW3
NW3
NW3
W1
SW1
W3
NW2
NW3
N3
G6
N5
G8
N7
NW7
G10
NW11
G14
NW12
2 days
ago
W12
NW8
G11
NW10
W12
NW5
G8
NW6
G10
N4
NW3
NW2
NW3
NW2
NW4
NW4
NW5
NW5
NW4
NW1
N5
NW8
G11
N6
NW7
NW10
NW10
NW14

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Half Moon Bay Airport, CA3 mi32 minNW 125.00 miFair with Haze63°F51°F68%1013.9 hPa
San Francisco, San Francisco International Airport, CA12 mi31 minWNW 2010.00 miFair and Breezy74°F48°F41%1011.4 hPa
San Carlos Airport, CA13 mi1.7 hrsN 910.00 miClear81°F59°F48%1011.5 hPa
Palo Alto Airport, CA19 mi27 minN 1510.00 miClear77°F60°F57%1010.8 hPa
Oakland, Metro Oakland International Airport, CA21 mi34 minWNW 1610.00 miFair76°F54°F47%1011.4 hPa
Hayward, Hayward Air Terminal, CA23 mi33 minWNW 1410.00 miFair80°F48°F34%1011.9 hPa

Link to 5 minute data for KHAF

Wind History from HAF (wind in knots)
5
PM
6
PM
7
PM
8
PM
9
PM
10
PM
11
PM
-12
PM
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
Last 24hrNW15NW12
G17
NW9NW8NW5CalmCalmCalmCalmCalmCalmCalmNE3NE3CalmCalmW5W6W7W6NW9NW8NW11NW14
1 day agoNW8NW7NW7W4CalmCalmCalmE3CalmCalmCalmCalmCalmCalmCalmCalmW6NW8W8NW10NW7NW11
G15
NW12NW12
2 days agoNW10NW11
G14
NW7NW5NW4CalmNW7NW7CalmN5N4NW5NW6NW4NW4NW4NW5NW6NW7NW10NW8NW8W8NW8

Tide / Current Tables for Half Moon Bay, California
   EDIT   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Half Moon Bay
Click for Map
Sun -- 12:42 AM PDT     Moonrise
Sun -- 04:09 AM PDT     3.67 feet High Tide
Sun -- 05:59 AM PDT     Sunrise
Sun -- 10:32 AM PDT     1.28 feet Low Tide
Sun -- 01:13 PM PDT     Moonset
Sun -- 04:31 PM PDT     Last Quarter
Sun -- 05:19 PM PDT     4.94 feet High Tide
Sun -- 08:31 PM PDT     Sunset
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
2.42.83.13.53.73.63.22.72.11.61.31.31.72.33.244.64.94.94.53.93.22.62.1

Tide / Current Tables for San Mateo Bridge, South San Francisco Bay, California Current
   EDIT      (on/off)   Help   One Week of Data
San Mateo Bridge
Click for Map
Sun -- 12:41 AM PDT     Moonrise
Sun -- 01:53 AM PDT     0.00 knots Slack
Sun -- 04:10 AM PDT     0.77 knots Max Flood
Sun -- 05:58 AM PDT     Sunrise
Sun -- 07:20 AM PDT     -0.00 knots Slack
Sun -- 10:26 AM PDT     -0.98 knots Max Ebb
Sun -- 01:12 PM PDT     Moonset
Sun -- 01:44 PM PDT     0.00 knots Slack
Sun -- 04:31 PM PDT     Last Quarter
Sun -- 04:36 PM PDT     1.14 knots Max Flood
Sun -- 08:09 PM PDT     -0.00 knots Slack
Sun -- 08:31 PM PDT     Sunset
Sun -- 11:12 PM PDT     -1.02 knots Max Ebb
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
-0.7-0.40.10.50.80.70.50.2-0.3-0.7-1-0.9-0.6-0.30.10.71.11.110.60.1-0.4-0.8-1

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 (19,4,5,8)
      (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.