Thursday, December13, 2018 L-36.com


Marine Weather and Tides
Pacifica, CA

Version 3.4
What's New / NOTES
10/6/2018 Colors of tide XTide graphs changed to emphasize that they were upgraded. See next note. Comments welcome.
10/4/2018 I have fixed XTide and updated the harmonic files. There were some name changes so you might have to click EDIT to find the new station name.

Sunrise 7:15AMSunset 4:53PM Thursday December 13, 2018 1:33 AM PST (09:33 UTC) Moonrise 11:49AMMoonset 10:49PM Illumination 32% 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
PZZ545 Coastal Waters From Point Reyes To Pigeon Point California Out To 10 Nm- 810 Pm Pst Wed Dec 12 2018
.small craft advisory in effect until 9 pm pst this evening...
.small craft advisory for rough bar in effect through late Thursday night...
.small craft advisory in effect from late Thursday night through late Friday night...
Tonight..NW winds 5 to 15 kt...becoming northeast 5 to 10 kt after midnight. Wind waves 2 ft or less. W swell 6 to 9 ft at 15 seconds.
Thu..NE winds 10 to 20 kt with gusts up to 25 kt. Wind waves 2 ft or less. W swell 8 to 12 ft at 16 seconds and S around 2 ft at 15 seconds.
Thu night..SE winds 10 to 20 kt with gusts up to 25 kt. Wind waves 3 to 4 ft. W swell 7 to 10 ft at 16 seconds and S around 2 ft at 15 seconds.
Fri..S winds 15 to 25 kt with gusts up to 30 kt. Wind waves 3 to 5 ft. W swell 7 to 10 ft at 16 seconds and S around 2 ft at 14 seconds. Rain likely.
Fri night..S winds 10 to 20 kt with gusts up to 25 kt. Wind waves 3 to 4 ft. W swell 9 to 14 ft at 16 seconds and S around 2 ft at 13 seconds. A chance of showers.
Sat..SE winds 5 to 15 kt. Wind waves 2 ft or less. W swell 8 to 12 ft and S around 2 ft.
Sat night..SE winds 10 to 15 kt. Wind waves 2 ft or less. W swell 5 to 9 ft and S around 2 ft.
Sun..S winds 10 to 20 kt. Wind waves 3 to 4 ft. W swell 11 to 16 ft and S around 2 ft. Rain.
Mon..W winds around 5 kt. Wind waves 2 ft or less. W swell 13 to 18 ft and S around 2 ft. A chance of showers.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 6 to 9 ft with a dominant period of 15 seconds. Across the bar...combined seas 7 to 11 ft with a dominant period of 15 seconds. Maximum ebb current of 1.1 knots at 09:13 am Thursday and 1.9 knots at 08:07 pm Thursday.
PZZ500 810 Pm Pst Wed Dec 12 2018
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Northerly winds will gradually diminish across the waters tonight before turning southerly late Thursday night ahead of the next storm system set to arrive on Friday. Northwest swell will increase across the waters into tomorrow creating hazardous conditions, particularly for smaller vessels. A more significant long period northwest swell is then expected to arrive late Sunday into Monday. SWells across open water could reach or even exceed 20 feet.


7 Day Forecast for Marine Location Near Pacifica, CA
   Hourly   EDIT   Help
location: 37.62, -122.51     debug


Area Discussion for - San Francisco/Monterey Bay Area, CA
      (on/off)   Help   NOTE: mouseover dotted underlined text for definition
Fxus66 kmtr 130546
afdmtr
area forecast discussion
national weather service san francisco bay area
946 pm pst Wed dec 12 2018

Synopsis Dry conditions are forecast to continue across our
region through Thursday night. Daytime temperatures will be mild
while nights will be seasonably cool. Patchy fog could redevelop
tonight across the area, especially in the valleys. A weak
weather system will likely produce light rain later Friday and
Friday night, especially for areas north of the golden gate.

Periods of light rain may continue into Saturday, mainly for the
north bay. A stronger and wetter system is then expected to
produce widespread rain across our entire region Sunday afternoon
and Sunday night.

Discussion As of 9:45 pm pst Wednesday... No short term updates
tonight. Some thin high clouds are spilling over the ridge which
may be just enough cloud coverage to keep widespread valley fog
formation in check. Current forecast has late night fog confined
to the north and east bay valleys and will leave that as is for
now. So far only half moon bay is reporting some low clouds at 300
feet. Highs today were in the 60s regionwide and expect similar
conditions for Thursday as high pressure noses over the region.

Next cold front approaches the north bay by Friday afternoon. Some
stray coastal clouds showers sprinkles could develop for the santa
cruz mtns and big sur hills as moist onshore flow returns Friday
afternoon but the best chance of light ran will be pt reyes
northward. Model runs have been consistent in weakening this
feature as it tries to push southward Friday night with little or
no rain south of the golden gate.

Remnant moisture stalled boundary will hang up over the north bay
on Saturday where some lingering stray showers will be possible
while the rest of the area will remain dry and seasonably mild.

Clouds will increase Sunday ahead of the next organized trough
and surface front. Expect steady rain in the north bay by Sunday
afternoon and then overspreading the rest of the bay area Sunday
night with the main front and rains out of the region by Monday
morning. A large NW swell will reach the waters behind this front
with high surf advisories likely becoming necessary.

Gfs offers drying trend behind the Monday front with the euro
showing some warm advection rains for the north bay. New euro will
be in shortly but right now would lead towards drier pattern for
next week when looking over ensembles with 500 mb anti-cyclonic
flow.

Prev discussion As of 3:00 pm pst Wednesday... A low amplitude
upper ridge just off the coast will keep the storm track to our
north through Friday. Occasional high clouds continue to stream
from the northwest into the region this afternoon. The stratus and
localized fog this morning dissipated from all areas by early
afternoon, allowing temperatures to rise into the upper 50s to
lower 60s. The upper ridge axis will move overhead by Thursday
morning, with continued mostly clear skies and light winds. This
will allow strong radiational cooling to commence overnight, with
lows expected to drop into the 30s in the inland valleys and 40s
near the coast and sf bay. Patchy fog will again be possible,
especially near the sf bay and and the north and east bay valleys.

As the ridge axis moves overhead on Thursday, temperatures will be
mild once again. Highs will warm several degrees into the mid to
upper 60s in the lower elevations in our southern areas, and low
to mid 60s north. Skies will be mostly sunny creating a nice day
for the area.

The next system will arrive on Friday as a trough approaches from
the west. A narrow band of high precipitable water will accompany
the trough and move into the bay area by Friday evening. As moist
southwest flow increases ahead of the trough, light rainfall is
expected to develop by early afternoon across the higher terrain
of the central coast in the warm sector. The main band of rainfall
will accompany a cold front which will push into the bay area
from northwest to southeast Friday late afternoon through
evening. The front will weaken and stall, likely not making it south
of santa cruz. Rainfall amounts with this system will be light,
with up to a quarter inch from the bay area north in the populated
areas and lesser amounts to the south.

Scattered showers will be possible on Saturday where the stalled
frontal band and high pwat set up. Rainfall amounts with the
scattered showers will be light and no impacts are expected on
Saturday. A stronger storm system will then arrive on Sunday as a
deeper trough moves into the area. The euro keeps the trough more
consolidated as it moves through, while the GFS brings a deeper
trough through, forming into a closed low by early Monday. Light
prefrontal precipitation will develop on Sunday morning north of
the golden gate. Heavier precipitation will move into the north
bay on Sunday afternoon and spread south through Sunday night
across the area. The euro is about 6 hours faster on the timing of
the precipitation and heavier than the gfs. Have leaned more on
the euro for the time being. Rainfall amounts will be heavier with
this system, with widespread 0.5 to 1 inch in most populated
areas, 1 to 1.5 inches in the north bay valleys, santa cruz
mountains, and santa lucia mountains, and 1.5 to 2.5 inches in the
north bay mountains. Additionally, breezy to locally gusty winds
will develop ahead of the front near the coast and in the higher
terrain on Sunday.

Model differences increase on Monday and Tuesday. A ridge is
likely to develop in the east pacific to our southwest, but the
strength remains uncertain with a disturbance moving over the top
of the ridge. The GFS builds a stronger ridge and pushes all
precipitation well to our north, while the euro keeps the ridge
much flatter and allows precipitation to make it as far south as
the sf bay. For now, have gone with a model blend and have kept
slight chances of showers across the north. Models do agree that
the ridge will further amplify by Wednesday, bringing a return to
dry weather through the middle of next week.

Aviation As of 09:25 pm pst Wednesday... For 06z tafs.VFR
through the period aside from possible patchy fog in the early
morning around the north bay. Valley fog may develop and move into
the east bay in the early morning reducing vis for the east bay
taf sites. Expect passing high clouds at around 20,000 feet to
continue through the period. Winds will remain generally light.

Vicinity of ksfo...VFR with high clouds and generally light winds.

Sfo bridge approach... Similar to ksfo.

Monterey bay terminals...VFR through the period with high clouds
and light winds.

Marine As of 09:27 pm pst Wednesday... Northerly winds will
gradually diminish across the waters tonight before turning
southerly late Thursday night ahead of the next storm system set
to arrive on Friday. Northwest swell will increase across the
waters into tomorrow creating hazardous conditions, particularly
for smaller vessels. A more significant long period northwest
swell is then expected to arrive late Sunday into Monday. Swells
across open water could reach or even exceed 20 feet.

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: as
marine: as
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
FTPC1 - 9414290 - San Francisco, CA 13 mi33 min NE 2.9 G 5.1 1025.5 hPa (-0.4)
46237 - San Francisco Bar, CA (142) 13 mi33 min 56°F8 ft
PXOC1 - 9414311 - San Francisco (Pier 1), CA 14 mi33 min SE 6 G 7 53°F 1024.3 hPa (-0.3)
PXSC1 14 mi33 min 55°F 49°F
AAMC1 - 9414750 - Alameda, CA 15 mi39 min ESE 2.9 G 4.1 52°F 55°F1025.7 hPa
OKXC1 - 9414776 - Oakland (Berth 34), CA 16 mi33 min ESE 1.9 G 4.1 51°F 1025.5 hPa (+0.0)
OBXC1 16 mi33 min 52°F 48°F
OMHC1 - 9414769 - Oakland Middle Harbor Met, CA 16 mi33 min ESE 1.9 G 4.1
LNDC1 17 mi33 min SE 2.9 G 2.9 52°F 1025.3 hPa (-0.3)
RTYC1 - 9414523 - Redwood City, CA 18 mi33 min Calm G 2.9 47°F 55°F1025.8 hPa (-0.3)
TIBC1 - Tiburon Pier, San Francisco Bay, CA 19 mi40 min Calm 49°F 1026 hPa (+0.0)
46026 - SAN FRANCISCO - 18NM West of San Francisco, CA 20 mi23 min ENE 7.8 G 12 55°F 57°F1025.2 hPa
PPXC1 - 9414847 - Richmond (Point Potrero), CA 21 mi33 min NNE 4.1 G 4.1 52°F 1025.8 hPa (+0.0)
RCMC1 - 9414863 - Richmond, CA 22 mi33 min N 2.9 G 4.1 55°F1025.2 hPa
DPXC1 - 9415141 - Davis Point, San Pablo Bay, CA 33 mi33 min SSW 1.9 G 2.9 49°F 1025.4 hPa (+0.0)
MZXC1 - 9415102 - Martinez-Amorco CA 35 mi33 min N 2.9 G 2.9 49°F 53°F1025.7 hPa49°F
PRYC1 - 9415020 - Point Reyes, CA 36 mi33 min 56°F1025.1 hPa (-0.4)
PCOC1 - 9415144 - Port Chicago, CA 39 mi33 min S 1.9 G 4.1 48°F 53°F1025.7 hPa (+0.0)
PSBC1 - 9415115 - Pittsburg (Suisun Bay), CA 44 mi33 min ENE 1.9 G 2.9 49°F 1025.6 hPa (+0.0)
SFXC1 - San Francisco Bay Reserve, CA 48 mi48 min N 1.9 39°F 1025 hPa36°F

Wind History for San Francisco, CA
(wind in knots)    EDIT      (on/off)   Help
1
AM
-12
PM
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
12
AM
Last
24hr
S4
W2
--
S2
E10
NE7
NE12
G16
NE8
G12
NE11
N6
NE5
NE2
W7
G10
S3
SW4
SW6
SW7
SW4
S2
SW1
SW2
S3
SE2
G5
1 day
ago
SW4
S3
S1
NE3
G6
E4
G7
E4
--
SE3
NE2
NE3
NE3
NE2
N2
SW5
W4
G7
SW4
G7
S3
SW2
W4
--
S2
S2
SW2
NE1
2 days
ago
N9
N11
N10
N7
N7
N11
N7
NE5
N3
NW2
NW4
G8
W6
SW2
SW2
SW3
S2
S3
SW2
S1
S1

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports
AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Half Moon Bay Airport, CA8 mi38 minN 010.00 miOvercast41°F39°F93%1025.1 hPa
San Francisco, San Francisco International Airport, CA8 mi37 minN 010.00 miA Few Clouds47°F39°F74%1025 hPa
San Carlos Airport, CA15 mi38 minN 010.00 miFair45°F39°F81%1025.4 hPa
Oakland, Metro Oakland International Airport, CA16 mi40 minESE 410.00 miA Few Clouds49°F41°F74%1025.5 hPa
Hayward, Hayward Air Terminal, CA21 mi39 minN 310.00 miFair50°F37°F63%1026.3 hPa
Palo Alto Airport, CA23 mi4.8 hrsN 010.00 miClear50°F42°F76%1026.1 hPa

Wind History from HAF (wind in knots)
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
-12
PM
1
AM
Last 24hrNW8NW5NW11N9N8N4CalmE4CalmN6N6NW9
G15
N13
G17
N13
G20
N7N9
G15
N4N3N6CalmCalmNE3CalmCalm
1 day agoCalmCalmCalmCalmCalmCalmCalmN5NW8NW7NW9NW7NW10N7N10N5CalmN9N8NW14
G18
N10NW10N8
G15
N5
2 days agoCalmNW3CalmCalmCalmN4N3NE11NE5NE7NE8E8NE10N11
G15
NW9N7N6N5N4CalmNE3CalmCalmCalm

Tide / Current Tables for Seaplane Harbor, San Francisco Bay, California
   EDIT   RT Ports Option   Weekend mode (on/off)   (on/off)   Help   One Week of Data
Seaplane Harbor
Click for Map
Thu -- 05:13 AM PST     6.17 feet High Tide
Thu -- 07:16 AM PST     Sunrise
Thu -- 10:52 AM PST     3.19 feet Low Tide
Thu -- 11:48 AM PST     Moonrise
Thu -- 03:37 PM PST     5.98 feet High Tide
Thu -- 04:51 PM PST     Sunset
Thu -- 10:44 PM PST     0.55 feet Low Tide
Thu -- 10:49 PM PST     Moonset
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
1.42.63.855.86.265.44.63.93.33.23.54.35.15.85.95.64.73.62.31.30.70.6

Tide / Current Tables for Sierra Point 1.3 mi ENE, South San Francisco Bay, California Current
   EDIT      (on/off)   Help   One Week of Data
Sierra Point 1.3 mi ENE
Click for Map
Thu -- 01:43 AM PST     0.86 knots Max Flood
Thu -- 05:20 AM PST     -0.01 knots Slack
Thu -- 07:16 AM PST     Sunrise
Thu -- 07:47 AM PST     -0.58 knots Max Ebb
Thu -- 11:02 AM PST     0.00 knots Slack
Thu -- 11:48 AM PST     Moonrise
Thu -- 01:35 PM PST     0.44 knots Max Flood
Thu -- 04:17 PM PST     -0.00 knots Slack
Thu -- 04:51 PM PST     Sunset
Thu -- 07:50 PM PST     -0.99 knots Max Ebb
Thu -- 10:49 PM PST     Moonset
Thu -- 11:14 PM PST     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
0.60.80.90.70.50.1-0.3-0.5-0.6-0.4-0.2-00.20.40.40.30.1-0.2-0.6-0.9-1-0.8-0.5-0.1

Weather Map and Satellite Images
       (on/off)   HelpWeather Map
wmap_P
GOES 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 (4,6,7,8)
      (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.