Marine Weather and Tides
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 7:19AM||Sunset 5:24PM||Sunday January 21, 2018 4:56 AM PST (12:56 UTC)||Moonrise 10:05AM||Moonset 9:57PM||Illumination 23%|
EDIT (on/off)  Help
|PZZ545 Point Reyes To Pigeon Point To 10 Nm- 212 Am Pst Sun Jan 21 2018 |
.small craft advisory in effect through Monday afternoon...
Today..NW winds 10 kt...becoming sw in the afternoon. Wind waves 2 ft or less...becoming 3 ft in the afternoon. W swell 7 to 9 ft at 12 seconds. Chance of rain in the afternoon.
Tonight..S winds 15 to 25 kt. Wind waves 3 to 5 ft. W swell 9 to 11 ft at 14 seconds. Rain likely.
Mon..S winds 15 to 25 kt...becoming sw 5 to 15 kt in the afternoon. Wind waves 3 to 5 ft. W swell 9 to 12 ft at 15 seconds. Slight chance of rain in the morning.
Mon night..NW winds 10 kt. Wind waves 2 ft or less. W swell 8 to 10 ft at 14 seconds.
Tue..E winds 5 to 15 kt...becoming nw. Wind waves 1 to 3 ft. W swell 6 to 8 ft at 16 seconds.
Wed..SW winds 15 to 25 kt. Wind waves 3 to 5 ft. W swell 5 to 7 ft...increasing to 8 to 10 ft. Chance of rain.
Thu..W winds 10 to 20 kt. Wind waves 2 to 4 ft. W swell 12 to 15 ft...decreasing to 11 to 14 ft. Chance of showers.
...san francisco bar/fourfathom bank forecast..... In the deep water channel...combined seas 7 to 9 ft at 12 seconds. Across the bar...combined seas 7 to 9 ft at 12 seconds. Maximum ebb current of 1.6 knots at 07:19 am Sunday and 2.7 knots at 06:55 pm Sunday.
|PZZ500 212 Am Pst Sun Jan 21 2018 |
Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Winds will increase and become southwesterly later this morning, especially for the northern coastal waters, ahead of an arriving weak cold front. The cold front is forecast to pass through Monday morning and will switch winds out of the north again. Small craft advisories are in place for most coastal water zones mainly due to squared and hazardous seas over the next couple of days. A new northwest swell train arrives by this evening.
7 Day Forecast for Marine Location Near El Granada, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus66 kmtr 211202|
area forecast discussion
national weather service san francisco bay area
402 am pst Sun jan 21 2018
Synopsis Dry and cool weather is forecast to continue across
our entire area through at least midday Sunday. The next system
is expected to spread rain across primarily the northern portion
of the forecast area late Sunday and Sunday night. The weather
pattern will remain active into next week, with more rain likely
Discussion As of 8:55 pm pst Saturday... After a cool start
this morning, afternoon highs reached seasonable mid and upper
50s. Expect another cool night tonight, but not quite as cool as
last night since the airmass over our region has begun to moderate
and high clouds are starting to increase.
Evening IR satellite imagery shows a band of clouds associated
with a frontal boundary extending from near the ca or border west-
southwest across the northeast pacific. Moisture within this
boundary is relatively plentiful with precipitable water values
approaching 1.5 inches. The models agree that this frontal
boundary will sag slowly to the southeast over the next 36 hours,
and bring rainfall to much of our forecast area from late Sunday
through early Monday. Recent model output has slowed the southward
progression of the boundary and thus delayed the onset of
precipitation. Rain is not expected to develop in the north bay
until mid-to-late afternoon Sunday, with rain then forecast to
gradually spread across most of the rest of the sf bay area by
late Sunday night. Rain may then reach as far south as the
monterey bay area by Monday morning before the frontal boundary
The bulk of the rainfall with this system is expected to be
generated by warm advection processes and fall across northern
california, generally north of i-80. Rainfall amounts are
projected to fall off precipitously to the south of i-80. In our
forecast area, only the north bay is expected to pick up
significant precipitation with this system. Rainfall will
initially be light in the north bay on Sunday afternoon, but rain
rates are then expected to increase Sunday evening with periods of
heavy rain possible across portions of the north bay from late
Sunday evening through late Sunday night. However, model rainfall
amounts have recently been trending lower. For instance,
yesterday the NAM and GFS were forecasting as much as 2.5 inches
of rain with this system in the north bay. Now, the latest nam
and GFS (00z runs) forecast maximum rainfall values of only about
half that much. And, rain totals across the north bay burn scars
are now forecast by the NAM and GFS to be only slightly more than
a half inch. Of course, these courser-scale models tend to miss
some of the orographic enhancement and therefore tend to
underestimate rainfall maxima. So we still could see locally as
much as 2 inches of rain in northwest sonoma county and as much as
an inch or more across the burn scars. In any event, concern for
debris flows flash flooding in and near the north bay burn scars
has decreased now that the models are trending somewhat drier.
Besides trending drier, the models have also shown a trend towards
less wind with this upcoming system. Southerly winds may gust
locally as high as 35 mph along the north bay coast late Sunday
afternoon and Sunday evening, but winds are not expected to reach
Rain is expected to linger into Monday morning as the frontal
boundary dissipates over the southern portion of our area. Most
models end all rain by midday Monday. Dry weather is expected to|
return by Monday afternoon and temperatures will be mild due to
lack of cold advection with this system.
Shortwave ridging is forecast to maintain dry and mild conditions
from Monday afternoon through Tuesday and Tuesday night. The next
system is expected to bring rain to our area area Wednesday and
Wednesday night. This midweek system is forecast drive a strong
cold front through our entire forecast area, which will mean a
potential for soaking rains regionwide. Brief heavy rain and locally
strong and gusty winds may also be factors with the midweek
system. Showers will linger into Thursday, with a return to dry
weather conditions expected by late in the week.
Aviation As of 3:59 am pst Sunday for 12z tafs. Current fog
product shows streaming high clouds overhead, with no signs of
stratus across the district. However, lastest ksts and kapc obs
are now reporting light patchy fog. Expect intermittent fog
through 15-16z for north bay terminals. Still monitoring for low
clouds fog development around the greater san francisco bay area
over the next couple of hour, hinted by the 00z mtrwrf model. Kept
tempo group in TAF for koak and ksfo through 15z, just in case.
Dewpoint depressions at ksfo and koak are 6f and 0f, respectively.
An upper level system approaching the bay area will introduce
rain beginning this afternoon for the north bay, therefore
lowering CIGS in the process. Current thinking is rain will begin
around or slightly after 00z Mon at ksts, then progress southward
through the sf bay area by 03-05z. It looks like rain will affect
monterey bay terminals after 12z mon. Rainfall may be moderate
and occasionally heavy at times. This will likely drop CIGS vsby
down to ifr or lifr during heavier showers. Winds are expected to
be mainly southwesterly southerly through the forecast period,
between 08-12 kt.
Vicinity of ksfo... Slight chance of MVFR CIGS through 15z this
morning. OtherwiseVFR expected through this afternoon. CIGS will
gradually lower through the afternoon and are expected to be MVFR
this evening. Light east southeast winds this morning will turn
more southerly southwesterly and increase by afternoon.
Sfo bridge approach... Similar to ksfo.
Monterey bay terminals...VFR conditions are expected to prevail
through the forecast period, with high cloud. Generally light
winds. Rain chances increase after 12z Monday.
Marine As of 2:35 am pst Sunday... Winds will increase and
become southwesterly later this morning, especially for the
northern coastal waters, ahead of an arriving weak cold front. The
cold front is forecast to pass through Monday morning and will
switch winds out of the north again. Small craft advisories are in
place for most coastal water zones mainly due to squared and
hazardous seas over the next couple of days. A new northwest swell
train arrives by this evening.
Mtr watches warnings advisories
Tday Sca... Pt arena to pt reyes 0-10 nm
sca... Pt reyes to pigeon pt 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... Sf bay from 3 pm
public forecast: dykema
visit us at
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Wind History for Redwood City, CA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports
|Half Moon Bay Airport, CA||1 mi||62 min||N 0||10.00 mi||Fair||39°F||37°F||93%||1025.1 hPa|
|San Francisco, San Francisco International Airport, CA||10 mi||61 min||N 0||10.00 mi||Fair||44°F||37°F||79%||1025.8 hPa|
|San Carlos Airport, CA||12 mi||62 min||N 0||10.00 mi||Fair||39°F||37°F||93%||1026.1 hPa|
|Oakland, Metro Oakland International Airport, CA||20 mi||64 min||ENE 3||10.00 mi||Fair||38°F||37°F||100%||1026.2 hPa|
|Hayward, Hayward Air Terminal, CA||22 mi||63 min||E 3||10.00 mi||Fair||39°F||34°F||82%||1026.9 hPa|
|Mountain View, Moffett Field, CA||23 mi||61 min||N 0||10.00 mi||Fair||39°F||36°F||89%||1026.5 hPa|
Wind History from SFO (wind in knots)
|1 day ago||SW||SW||Calm||W||W||E||NE||NW||W||W||W||W||W||W||W||W||W||W||W||W||NW||NW||W|
|2 days ago||SE||SE||SE||Calm||Calm||E||E||SE||W||W||W||W||W||W||NW||W||N||Calm||Calm||W||W||SW||S||W |
EDIT RT Ports Option Weekend mode (on/off) (on/off)  Help One Week of Data
Click for Map
Sun -- 01:36 AM PST 4.78 feet High Tide
Sun -- 07:04 AM PST 2.65 feet Low Tide
Sun -- 07:20 AM PST Sunrise
Sun -- 10:04 AM PST Moonrise
Sun -- 12:40 PM PST 4.79 feet High Tide
Sun -- 05:22 PM PST Sunset
Sun -- 07:21 PM PST 0.39 feet Low Tide
Sun -- 09:57 PM PST Moonset
Tide / Current data from XTide NOT FOR NAVIGATION
EDIT (on/off)  Help One Week of Data
|San Mateo Bridge |
Click for Map
Sun -- 12:49 AM PST 1.57 knots Max Flood
Sun -- 04:33 AM PST -0.00 knots Slack
Sun -- 07:20 AM PST Sunrise
Sun -- 07:21 AM PST -1.04 knots Max Ebb
Sun -- 10:03 AM PST Moonrise
Sun -- 10:12 AM PST 0.00 knots Slack
Sun -- 12:50 PM PST 1.03 knots Max Flood
Sun -- 03:49 PM PST -0.01 knots Slack
Sun -- 05:20 PM PST Sunset
Sun -- 07:30 PM PST -1.48 knots Max Ebb
Sun -- 09:56 PM PST Moonset
Sun -- 10:32 PM PST 0.00 knots Slack
Tide / Current data from XTide NOT FOR NAVIGATION
Weather Map and Satellite Images(on/off)  Help
|Weather Map ||IR Satellite Image from GEOS|
GOES Local Image of CentralWestCoast EDIT
Wind Forecast for San Francisco/Monterey Bay Area, CA (7,2,3,4)(on/off)  Help
Ad by Google
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.