Thursday, October19, 2017 L-36.com


Marine Weather and Tides
San Mateo, 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 7:21AMSunset 6:26PM Thursday October 19, 2017 2:53 PM PDT (21:53 UTC) Moonrise 6:08AMMoonset 5:50PM Illumination 0% Phase: New Moon; Moon at 29 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
PZZ530 San Pablo Bay Suisun Bay The West Delta And San Francisco Bay North Of The Bay Bridge- 216 Pm Pdt Thu Oct 19 2017
.small craft advisory in effect from 9 pm pdt this evening through late tonight...
Tonight..W winds 15 to 25 kt. Chance of rain in the evening, then chance of showers after midnight.
Fri..W winds 10 to 20 kt.
Fri night..W winds 10 to 20 kt.
Sat..W winds 5 to 15 kt.
Sat night..NW winds 5 to 15 kt.
Sun..W winds 5 to 15 kt.
Mon..N winds 5 kt.
Tue..N winds 10 kt.
PZZ500 216 Pm Pdt Thu Oct 19 2017
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... A cold front will pass over the region later this evening, bringing the first rain of the wet season, a wind shift, and small craft criteria winds to the waters, with occasional gusts up to or exceeding 30 mph. A very robust northwest, long period, large swell train will arrive late this afternoon and through the evening, generating large waves and hazardous seas through at least Saturday. Operators of small crafts are urged to use extreme caution if out at sea over the next several days.

7 Day Forecast for Marine Location Near San Mateo, CA
   Hourly   EDIT   Help
location: 37.59, -122.31     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus66 kmtr 192052
afdmtr
area forecast discussion
national weather service san francisco bay area
152 pm pdt Thu oct 19 2017

Synopsis A cold front is still expected to move through the
area later today and tonight bringing widespread rainfall to the
region. The bulk of the rain will be in the north bay mountains
and coastal ranges. Along with precipitation, expect cooler
temperatures and breezy onshore winds through Friday. By late
Friday morning dry conditions will return lasting through the
forecast period. A warming trend is then on the way over the
weekend and into early next week. Temperatures are predicted to be
well above average during the beginning of next week.

Discussion As of 1:52 pm pdt Thursday... Current satellite
imagery showing parts of the bay area still under this morning's
stratus deck as the marine layer remains around 1500 ft. The
approaching cold front can also be seen on the satellite as it
nears the northern california coast. Rainfall is expected to reach
the sonoma and marin county coastal areas later this afternoon
before becoming more widespread late this evening and eventually
covering the remainder of the CWA by around midnight. Rainfall is
expected to be out of the san francisco bay area by tomorrow
morning's commute. Along with precipitation breezy southwesterly
winds will accompany the frontal passage.

Forecast rainfall totals have been updated to increase the amount
of precipitation for the north bay mountains. Latest model runs
indicate the north bay mountains could receive around 0.75" with
locally higher amounts possible in parts of sonoma county.

Otherwise, little changes have been made for the north bay
valleys. The santa cruz and santa lucia mountains are expected to
receive around 0.25" with less than two tenths of an inch
expected for most valley locations. Some areas in the southern and
far eastern portions of the CWA may see little to no rain. Cool
and breezy conditions are expected for the rest of the day Friday
after the precipitation has ended.

A warming trend is on tap for the weekend as an upper level ridge
starts to build over california. The ridge is expected to
strengthen as we head into the beginning of next week. 850 mb
temperatures are forecast to approach 25 degrees celsius through
mid week flirting with maximum climatological values for this
area. The ridge along with light offshore flow will result in warm
and dry conditions across the area Monday and Tuesday. Widespread
highs in the 80s and low to mid 90s are expected. Slight cooling
is possible on Wednesday for coastal areas, but warm conditions
will continue inland.

Aviation As of 11:15 am pdt Thursday... For 18z tafs. Mixed
ceilings with some lingering overnight stratus now mixing out and
some mid level clouds above obscuring the view on satellite.

Ceilings are ranging from ifr toVFR conditions around the region
and are anticipated to gradually improve through the late morning
into early afternoon, but deteriorate later today ahead of the
arrival of a cold frontal system. Winds will shift and become
breezy to occasionally gusty, especially over the north bay and
near ksfo koak as the FROPA occurs. Local WRF skew-t momentum
transfer indicates localized gusts up to around 30 knots will be
possible with the FROPA as winds mix down from above. Some
nocturnal decoupling with these winds aloft could also bring
localized low level wind shear, especially to ksfo ksts and kapc
as frontal passage occurs. Llws not yet added to tafs but will be
looked at closer with next issuance. Rain will primarily being
between 01z in the north bay and closer to 04-06z for the south
bay monterey bay. The heaviest amounts will be over the coastal
ranges and north bay hills and mountains, with lighter amounts
farther southward and inland. Rains will be sufficient to wet
runways. Ceilings will generally be borderline MVFR toVFR by
tomorrow morning in the wake of the front.

Overall forecast confidence: moderate
vicinity of ksfo... MVFR thru late morning becomingVFR until
around 03z where borderline MVFR CIGS return with fropa.

Breezy west winds 15 to 20 mph with gusts 25 to 30 mph possible
with fropa. Rain will wet runways but taper off but sunrise. Llws
a possibility with FROPA (light at surface gusting to 25-30mph at
2000ft agl). CIGS improving by sunrise fri.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals... Mixed ceilings, bouncing between ifr and
vfr through the morning, low confidence. Ceilings will deteriorate
by mid to late afternoon and drop firmly into the ifr band ahead
of fropa. Light onshore winds and light rain will accompany fropa.

Llws not a concern this far south from base of trough. Cigs
improving by sunrise fri.

Fire weather As of 3:43 am pdt Thursday... Relative humidity
recoveries have improved this morning with even most hilltop areas
seeing 80-100% values. Onshore winds will continue to gradually
increase today and moderate and locally gusty winds are expected.

Models continue to move an early season cold front through the
district late today and tonight. Rainfall will begin in the north
bay this afternoon and spread across most of the remainder of the
district tonight. The models have just recently trended slightly
wetter with this system, although rainfall amounts are still
expected to be mostly light. Wetting rains are most likely in the
north bay mountains and perhaps locally in the santa cruz
mountains. Rainfall should end in most areas by Friday morning.

Friday will be a cool day with brisk northwest winds.

A warming trend will begin over the upcoming weekend as a high
pressure ridge begins to build over california. This ridge will
strengthen into early next week and result in warm and dry
conditions districtwide from Monday through Wednesday. Will need
to be wary of possible gusty offshore winds in the hills by Sunday
night and especially Monday night.

Marine As of 2:47 am pdt Thursday... A cold front is forecast
to pass through the region later this evening. Winds will increase
along and just behind the front, occasionally gusting around 25
knots at times. Showers will be possible ahead of and along the
cold front, as well. A very robust northwest, long period swell
will arrive late this afternoon and through the evening,
generating large waves and hazardous seas through at least
Saturday. Operators of small crafts are urged to use extreme
caution if out at sea over the next several days.

Mtr watches warnings advisories
Tday Sca... Pt arena to pigeon pt 10-60 nm from 5 pm
public forecast: as
aviation: drp
marine: drp
fire weather: sims
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 8 mi54 min WSW 12 G 15 63°F 65°F1014.2 hPa (-1.4)
AAMC1 - 9414750 - Alameda, CA 13 mi54 min WSW 4.1 G 8 61°F 62°F1015 hPa (-1.4)
LNDC1 14 mi54 min WSW 7 G 9.9 61°F 1014.5 hPa (-1.3)
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 15 mi54 min SW 6 G 9.9
PXOC1 - 9414311 - San Francisco (Pier 1), CA 15 mi156 min WSW 5.1 G 8 60°F 1014.8 hPa
OBXC1 15 mi54 min 60°F 55°F
PXSC1 15 mi54 min 62°F 55°F
OKXC1 - 9414776 - Oakland (Berth 34), CA 15 mi54 min W 4.1 G 7 61°F 1014.4 hPa (-1.4)
FTPC1 - 9414290 - San Francisco, CA 17 mi54 min SW 11 G 16 60°F 57°F1014.8 hPa (-1.3)
46237 - San Francisco Bar, CA (142) 22 mi54 min 55°F4 ft
TIBC1 - Tiburon Pier, San Francisco Bay, CA 22 mi62 min W 5.1 58°F 1014 hPa (-2.0)
PPXC1 - 9414847 - Richmond (Point Potrero), CA 22 mi54 min SW 8 G 11 60°F 1014.8 hPa
RCMC1 - 9414863 - Richmond, CA 24 mi54 min SSW 5.1 G 8 59°F 59°F1014.4 hPa (-1.2)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 30 mi64 min S 7.8 G 9.7 54°F 55°F4 ft1014.9 hPa (-0.8)
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 32 mi54 min SW 13 G 16 60°F 1013.7 hPa
MZXC1 - 9415102 - Martinez-Amorco CA 32 mi54 min SW 12 G 17 62°F 63°F1014.1 hPa (-1.4)56°F
46012 - HALF MOON BAY - 24NM South Southwest of San Francisco, CA 34 mi64 min SSE 7.8 G 9.7 57°F 58°F5 ft1014.6 hPa (-1.1)
PCOC1 - 9415144 - Port Chicago, CA 35 mi54 min W 12 G 16 63°F 63°F1013.6 hPa (-1.5)
PRYC1 - 9415020 - Point Reyes, CA 45 mi54 min E 7 G 11 55°F1014.1 hPa (-1.4)
SFXC1 - San Francisco Bay Reserve, CA 45 mi69 min W 11 64°F 1013 hPa55°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
NW10
NW11
NW10
NW11
NW7
NW5
--
W3
NW3
W3
S3
SW4
W4
W6
S4
SE3
S3
SE2
S3
--
NW3
NW4
G8
W8
G11
W12
G15
1 day
ago
N5
NW9
NW7
N8
NW6
G10
NW4
N6
S1
NW6
NW6
NW4
W6
SW3
W3
SW3
SE1
SE2
S2
SW1
G4
SE1
NE1
N1
N4
N8
2 days
ago
N4
NW4
NW5
NW3
SW1
SE2
SE1
SE4
S1
S1
--
S1
SE2
NE1
--
SW3
--
SW1
S1
NW2
N3
NW3
N4
N4

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
San Francisco, San Francisco International Airport, CA3 mi58 minWSW 13 G 1810.00 miMostly Cloudy65°F52°F63%1014.4 hPa
San Carlos Airport, CA5 mi67 minWSW 1210.00 miMostly Cloudy66°F53°F64%1015.2 hPa
Oakland, Metro Oakland International Airport, CA9 mi61 minW 910.00 miMostly Cloudy63°F55°F76%1014.9 hPa
Hayward, Hayward Air Terminal, CA11 mi60 minWNW 810.00 miMostly Cloudy64°F51°F63%1015.8 hPa
Half Moon Bay Airport, CA11 mi59 minSSE 510.00 miOvercast59°F53°F82%1014.6 hPa
Palo Alto Airport, CA13 mi67 minN 910.00 miPartly Cloudy64°F0°F%1014.9 hPa
Mountain View, Moffett Field, CA18 mi58 minNNE 710.00 miMostly Cloudy65°F53°F66%1015 hPa

Wind History from SFO (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 24hrW19W21W17W17W15W12W6W10W11
G15
W7W5SW5W8W7W6W3W5W3SW4SW4SW5NW6SW11W13
G18
1 day agoNW8NW13NW14NW15NW12NW12W11W13W12W11NW14NW12W6W6W7W7W4CalmS5CalmE3E4N5NW14
2 days agoN3CalmCalmN3W9W5CalmCalmCalmCalmCalmCalmW5CalmCalmCalmS3CalmN3CalmE4N3NE4NW8

Tide / Current Tables for Coyote Point Marina, San Francisco Bay, California
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Coyote Point Marina
Click for Map
Thu -- 12:38 AM PDT     6.89 feet High Tide
Thu -- 06:35 AM PDT     1.03 feet Low Tide
Thu -- 07:07 AM PDT     Moonrise
Thu -- 07:21 AM PDT     Sunrise
Thu -- 12:12 PM PDT     New Moon
Thu -- 12:45 PM PDT     7.62 feet High Tide
Thu -- 06:25 PM PDT     Sunset
Thu -- 06:50 PM PDT     Moonset
Thu -- 07:11 PM PDT     0.08 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
6.76.86.14.93.421.21.11.93.24.86.37.47.66.95.53.82.10.70.10.41.42.94.5

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
Thu -- 01:43 AM PDT     -0.00 knots Slack
Thu -- 04:47 AM PDT     -1.39 knots Max Ebb
Thu -- 07:07 AM PDT     Moonrise
Thu -- 07:21 AM PDT     Sunrise
Thu -- 07:50 AM PDT     0.00 knots Slack
Thu -- 10:33 AM PDT     1.69 knots Max Flood
Thu -- 12:12 PM PDT     New Moon
Thu -- 01:45 PM PDT     -0.01 knots Slack
Thu -- 05:03 PM PDT     -1.71 knots Max Ebb
Thu -- 06:25 PM PDT     Sunset
Thu -- 06:50 PM PDT     Moonset
Thu -- 08:19 PM PDT     0.00 knots Slack
Thu -- 11:08 PM PDT     1.85 knots Max Flood
Tide / Current data from XTide NOT FOR NAVIGATION
Sorry tide depth graphs only, please select another station.
12am1am2am3am4am5am6am7am8am9am10am11am12pm1pm2pm3pm4pm5pm6pm7pm8pm9pm10pm11pm
1.40.7-0.2-0.9-1.3-1.4-1.2-0.70.21.11.61.71.30.7-0.2-1-1.5-1.7-1.5-1.1-0.30.71.51.8

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 (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

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.