Wednesday, November20, 2019 L-36.com


Marine Weather and Tides
Belvedere, CA

Version 3.4
NOTICE
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.
6/2/2019. Many thanks to a user for reporting an error on one of the Edit pages. The switch to PHP 7.2 caused many pages that previously worked to quit working. I fixed many but I still depend on users to report ones I missed. Please report errors HERE or send an email to me at L-36.com. Allen

Sunrise 6:53AMSunset 4:56PM Wednesday November 20, 2019 6:37 AM PST (14:37 UTC) Moonrise 12:00AMMoonset 1:47PM Illumination 40% Phase: Third Quarter Moon; Moon at 23 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 The San Francisco Bay North Of The Bay Bridge- 245 Am Pst Wed Nov 20 2019
.small craft advisory in effect until 2 pm pst this afternoon...
Today..N winds 15 to 25 kt with gusts up to 30 kt.
Tonight..N winds 5 to 10 kt.
Thu..E winds 5 to 15 kt.
Thu night..SW winds around 5 kt.
Fri..NE winds up to 10 kt.
Fri night..N winds up to 10 kt.
Sat..NW winds up to 10 kt.
Sun..NW winds 5 to 15 kt.
PZZ500 245 Am Pst Wed Nov 20 2019
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Gale force, northwest winds are forecast to continue over the northern and outer coastal waters through Wednesday morning and subsiding in the afternoon. Small craft advisories are in effect for the remainder of the coastal waters, including inside the north bay. Hazardous seas are expected Wednesday as the northwest swell reaches its peak by midday in addition to the strong northwest winds. By Thursday, the strong winds and waves subside. A long period northwest swell train will begin to move into the waters on Friday.


7 Day Forecast for Marine Location Near Belvedere, CA
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location: 37.83, -122.44     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
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ftp://tgftp.nws.noaa.gov/data/raw/fx/fxus66.kmtr.afd.mtr.txt <- there really should be an address herer AEFXUS66 KMTR 201158 AFDMTR Area Forecast Discussion National Weather Service San Francisco Bay Area 358 AM PST Wed Nov 20 2019

SYNOPSIS Gusty and dry offshore winds will continue over the North and East Bay Hills Mountains from tonight through early Thursday that will consequently result in critical fire weather conditions. Dry conditions, along with seasonable temperatures, are forecast from Thursday through the upcoming weekend. Rain chances return next week possibly impacting the Thanksgiving holiday.

DISCUSSION as of 03:25 AM PST Wednesday... Well that was an exciting afternoon and evening. After a prolonged period of no rain, when rain finally does fall it makes things interesting.

Especially when one an isolated lightning strike occurs over the Santa Cruz Mountains. The much talked about upper low was an overachiever yesterday afternoon and evening. Models had been rather consistent with rain chances over the coastal waters and Big Sur Coastal region. However yesterday afternoon models begin to show rain chances even farther north including the North Bay.

As it would turn out, the low pivoted southward across the region producing rain from the North Bay all the way south to the Big Sur Coast. A spotter called to even report a lightning strike in the Santa Cruz Mountains around midnight, which was eventually picked up by the lightning detection network. Rainfall amounts over the last 12 hours varied from less than 0.10 from Monterey Bay northward. Monterey southward had a prolonged period of wet upslope flow over the terrain resulting in 0.51" at White Rock Ridge near Carmel Valley.

For the rest of the night shower rain chances will continue to diminish from N to S as the upper low surges southward. KMUX radar imagery confirms this thinking with only a few lingering showers over the coastal waters. Consequently, as the upper low moves southward the concerns shifts to gusty N to NE winds with drying conditions over the North Bay Mts East Bay Hills. This also can already be seen as Mt St Helena is gusting to 58 mph with decreasing relative humidity. The SFO-WMC pressure gradient has also shifted to offshore as well.

As offshore really takes hold through the day the airmass will continue to dry. Gusty offshore flow and dry conditions will keep critical fire weather conditions in place over the North and East Bay higher terrain. No changes to current Red Flag Warning. See fire section below for more details.

Winds will ultimately diminish through the day on Thursday as the gradient relaxes, but humidity remains low. The hi-res WRF models still shows a southerly surge moving up the coast and even the National Blend shows it too. Therefore, clouds and cooler temperatures will impact the coast on Thursday. Another upper low drifts southward off the CA Coast on Friday, but it appears to be far enough west to keep the Bay Area dry.

Ridge of high pressure begins to nose over the region late Friday and over the weekend keeping dry weather in place with a slight warming trend. Despite warmer daytime temperatures nights will remain cold in the valleys with lighter winds and clear skies.

Both the GFS and EC show another offshore flow event impacting the Bay Area beginning Sunday night Monday and continuing into Tuesday. Fire weather concerns will return as RH will lower again with gusty winds.

The middle and second half of next week continue to be rather interesting as long range models show an active weather pattern.

Given the holiday and expected travel impacts could be on the higher side. Run to run consistency has been lacking so confidence is marginal on the details, but all runs show some precip. The 06Z GFS for instance now shows a bowling ball of a low dropping far westward and into NorCal next Wednesday. The more consistent, and better model as of late, EC keeps the low more eastward with an "inside slider" feel to it. That solution would still bring some precip to the region, but not as much. Current forecast will align more with EC solution. Stay tuned as wet weather may impact Thanksgiving.

AVIATION as of 03:50 AM PST Tuesday... for 12z TAFs. With the exception of some lingering mid-level clouds providing MVFR conditions through the morning,VFR conditions expected across the Bay Area Wednesday as the cold front has passed through the region.

The main impact to terminals Wednesday will be the strong winds at the surface with stronger wind gusts possible. The main change from the last set of TAFs AFD was that the chance for low level north-northeast wind shear listed for Wednesday morning was removed. With higher terrain observations only showing 20-25 kts sustained around 1000-1500 feet, it lowered confidence of occurrence. It will be monitored and amendments issued if needed.

Winds switch to the northeast by this evening, and eventually subside.

Vicinity of KSFO...VFR conditions with the exception of a few lingering mid-level clouds. Strong and gusty northwest surface winds expected Wednesday. Winds will shift to the north-northeast in the late afternoon evening, and eventually subside with mostly clear skies.

SFO Bridge Approach... Similar to KSFO.

Monterey Bay Terminals... Northwest winds continue Wednesday morning. MostlyVFR conditions, though lingering mid-level clouds remain near the terminals. Expect winds to strengthen this afternoon. By Wednesday evening,VFR conditions are expected to hold as the winds switch to the south-southeast Wednesday night into Thursday morning.

FIRE WEATHER as of 03:25 AM PST Wednesday... In less than one hour the Red Flag Warning will go into effect for the North and East Bay Hills Mountains through 7 AM PST Thursday. Automated stations across the warned area are already gusty (Mt St Helena up to 58 mph) with RH gradually lowering. The trend will continue through the day as NE flow enhances the drying component. The recent showers may have briefly impacted the fine dead fuels, but with the increasing NE flow they'll return to critical levels.

Live fuel moisture remain at or below critical levels for November. This is a marginal Red Flag Event when looking at humidity levels, but the winds and fuels are the main driver of fire concerns. For what it's worth the hot dry windy index still shows values across the North Bay at 300 or above the 95th percentile.

Fire weather concerns will return early next week as medium range models suggest another round of offshore flow impacting the region and potentially more widespread. Hot dry windy index shows values increasing to nearly 400 by Monday. Stay tuned- fire season is definitely not over yet until the region receives widespread wetting rainfall.

MARINE as of 03:57 AM PST Wednesday... Gale force, northwest winds are forecast to continue over the northern and outer coastal waters through Wednesday morning and subsiding in the afternoon. Small craft advisories are in effect for the remainder of the coastal waters, including inside the North Bay. Hazardous seas are expected Wednesday as the northwest swell reaches its peak by midday in addition to the strong northwest winds. By Thursday, the strong winds and waves subside. A long period northwest swell train will begin to move into the waters on Friday.

MTR WATCHES WARNINGS ADVISORIES Tday Red Flag Warning... CAZ507-511 SCA... SF Bay until 2 PM SCA... Pigeon Pt to Pt Pinos 0-10 nm until 2 PM SCA... Pt Pinos to Pt Piedras Blancas 0-10 nm until 2 PM GLW... Pt Arena to Pigeon Pt 10-60 nm GLW... Pt Arena to Pt Reyes 0-10 nm until 8 AM GLW... Pt Reyes to Pigeon Pt 0-10 nm until 8 AM GLW... Pigeon Pt to Pt Piedras Blancas 10-60 nm until 8 AM PUBLIC FORECAST: MM AVIATION: DK MARINE: DK FIRE WEATHER: MM Visit us at
Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
FTPC1 - 9414290 - San Francisco, CA 2 mi55 min WSW 1.9 G 2.9 56°F 56°F1001.1 hPa
PXOC1 - 9414311 - San Francisco (Pier 1), CA 3 mi49 min W 6 G 8.9 58°F 999.8 hPa
PXSC1 3 mi49 min 59°F 42°F
TIBC1 - Tiburon Pier, San Francisco Bay, CA 4 mi68 min NW 8 56°F 1001 hPa
OBXC1 6 mi49 min 56°F 47°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 6 mi49 min N 6 G 7 56°F 1000.8 hPa
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 6 mi55 min N 5.1 G 7
RCMC1 - 9414863 - Richmond, CA 7 mi55 min NW 6 G 8 58°F 57°F1000.3 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 7 mi49 min NW 5.1 G 8.9 60°F 1001 hPa
AAMC1 - 9414750 - Alameda, CA 8 mi55 min NNW 2.9 G 6 55°F 58°F1001.1 hPa
LNDC1 9 mi49 min N 5.1 G 8 56°F 1000.6 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 18 mi49 min SSE 7 G 8 54°F 1000.3 hPa
UPBC1 22 mi49 min NW 5.1 G 7
MZXC1 - 9415102 - Martinez-Amorco CA 22 mi55 min W 5.1 G 6 56°F 59°F1000.8 hPa
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 22 mi27 min NW 16 G 21 54°F 54°F1001.8 hPa
RTYC1 - 9414523 - Redwood City, CA 25 mi49 min WSW 2.9 G 4.1 53°F 61°F1001.6 hPa
PCOC1 - 9415144 - Port Chicago, CA 26 mi49 min SSW 5.1 G 8.9 53°F 58°F1000.3 hPa
PRYC1 - 9415020 - Point Reyes, CA 31 mi49 min 53°F1001.3 hPa
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 33 mi55 min NW 8 G 12 59°F 1000 hPa
SFXC1 - San Francisco Bay Reserve, CA 34 mi52 min N 8 57°F 1000 hPa38°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 40 mi27 min NNW 19 G 27 55°F 57°F1001.8 hPa50°F

Wind History for San Francisco, CA
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Oakland, Metro Oakland International Airport, CA15 mi44 minN 010.00 miMostly Cloudy48°F41°F77%1000.8 hPa
San Francisco, San Francisco International Airport, CA15 mi1.7 hrsW 1110.00 miA Few Clouds52°F45°F77%1000.6 hPa
Hayward, Hayward Air Terminal, CA21 mi43 minESE 410.00 miFair47°F41°F80%1001.8 hPa
Half Moon Bay Airport, CA22 mi42 minNNW 65.00 miFair with Haze54°F48°F82%1001.4 hPa
Concord, Buchanan Field, CA23 mi44 minN 010.00 miFair47°F41°F80%999.4 hPa
San Carlos Airport, CA23 mi42 minN 010.00 miFair52°F42°F72%1001.4 hPa
Novato / Gnoss Field, CA23 mi62 minNW 1310.00 miFair57°F37°F48%1000.7 hPa

Link to 5 minute data for KSFO

Wind History from SFO (wind in knots)
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1 day agoCalmN5CalmN7NE5N5E4E4E54W14W19W16W19W11W10W11W11W18
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2 days agoCalmS3CalmN4NE33N3N3N3NW5W9W11W6W5S3CalmCalmCalmCalmCalmCalmS4SE3Calm

Tide / Current Tables for Alcatraz Island, San Francisco Bay, California
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Alcatraz Island
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Wed -- 06:51 AM PST     5.25 feet High Tide
Wed -- 06:55 AM PST     Sunrise
Wed -- 12:25 PM PST     2.48 feet Low Tide
Wed -- 01:46 PM PST     Moonset
Wed -- 04:55 PM PST     Sunset
Wed -- 05:56 PM PST     4.82 feet High Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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0.10.61.42.43.54.45.15.24.94.33.52.92.52.52.93.54.14.64.84.63.82.81.70.8

Tide / Current Tables for Alcatraz Island W, San Francisco Bay, California Current
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Alcatraz Island W
Click for Map
Wed -- 12:59 AM PST     0.00 knots Slack
Wed -- 04:14 AM PST     2.73 knots Max Flood
Wed -- 06:55 AM PST     Sunrise
Wed -- 07:57 AM PST     -0.01 knots Slack
Wed -- 10:19 AM PST     -1.57 knots Max Ebb
Wed -- 01:44 PM PST     0.00 knots Slack
Wed -- 01:46 PM PST     Moonset
Wed -- 04:24 PM PST     1.70 knots Max Flood
Wed -- 04:55 PM PST     Sunset
Wed -- 07:27 PM PST     -0.01 knots Slack
Wed -- 10:28 PM PST     -2.26 knots Max Ebb
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.

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-0.901.32.32.72.62.11.2-0.1-1-1.5-1.5-1.1-0.50.31.21.71.61.20.5-0.5-1.5-2.2-2.2

Weather Map
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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.
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Wind Forecast for San Francisco/Monterey Bay Area, CA (9,2,3,4)
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Ground Weather Radar Station San Francisco Bay Area, CA
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