Marine Weather and Tides
7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.
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|Sunrise 6:31AM||Sunset 7:49PM||Saturday August 24, 2019 5:06 AM PDT (12:06 UTC)||Moonrise 12:00AM||Moonset 2:05PM||Illumination 35%|
7 Day Forecast for Marine Location Near Twin Lakes CDP, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus66 kmtr 241158|
area forecast discussion
national weather service san francisco bay area
458 am pdt Sat aug 24 2019
Synopsis High pressure will bring a fairly seasonable weather
pattern to the bay area this weekend into early next week. The
marine layer will persist along the coast along with onshore flow
keeping temperatures warm near the coast and bays. Inland
temperatures will trend hotter as the strong high pressure builds.
Remnants of tropical storm ivo will pass offshore Tuesday and
Wednesday with increasing clouds and higher humidity developing.
Discussion As of 3:35 am pdt Saturday... Fairly strong high
pressure ridge will stretch from the eastern pacific to over
california and towards arizona. Heights will rise to around 594 dm
over the bay area by this afternoon and then hold fairly steady
through about Tuesday. The fort ord profiler shows the marine
layer as deep as 2500 feet but on average it looks to be closer to
2000 feet across the region early this morning. In general the
strong ridge should start to compress the layer but low level
southerly flow continues to advect marine air locally into the bay
and valleys. Despite the strong ridge the 850 mb temps are only
around 21-22 celsius this weekend. This in combination with
onshore flow will keep things from getting too hot. In general the
ridge will allow temps to trend a few degrees above normal but
expecting mainly 70s 80s around the bay with 90s farther inland.
No big changes of note Sunday and Monday but the trend should be
for hotter temps inland as mid and upper 90s become more
widespread due to the ridge strengthening and the marine layer
compressing. Heat risk values become moderate through the period
for the interior valleys but the lack of widespread triple digit
heat should preclude the need for any headlines. Overall trend for
above normal temps but nothing too out of the ordinary for late
The most interesting weather item to monitor will continue to be
the remnants of tropical storm ivo moving northward. The models
continue to be fairly consistent in their handling of this feature
as it shifts northward and interacts with the strong ridge. While
we continue to mention the increase in mid high clouds as well as
higher dewpoints as this feature passes offshore Tuesday and
Wednesday the main concern for the state will be the possibility
The general model consensus has been to keep the main moisture and
instability well offshore, west of point conception and big sur on
Tuesday. However, the 06z GFS brings the moisture and instability
closer to shore and clips the north bay with some elevated values
of most unstable CAPE as well as modified total totals in excess
of 30. In fact the 06z GFS even generates some spotty QPF over
the north bay early weds morning. As we've been mentioning in
previous discussions the details of the storm track will remain
fluid. The conceptual model strongly suggests there will be some
type of convective activity associated with this feature as the|
tropical moisture and decaying low interact with the upper ridge
and an incoming mid-latitude shortwave. However and this is to be
stressed, at this time the best chance for t-storms looks to be
north and east of the bay area (think trinity alps, mt shasta,
modoc, northern sierra). That being said cant rule out a scenario
where our CWA is impacted (and at this time the north bay would be
in the 5-10% range late Tuesday night early weds am). Due to the
nature of the system, any lightning would tend to be wet.
However, fuels are trending to their driest levels this summer and
an abundant lightning event could lead to new starts. So that
remains a very low probability scenario but worth monitoring as
impacts could be significant.
The disturbance should quickly move northward by later weds
afternoon evening followed by rebuilding high pressure and a
return of dry seasonable wx.
Aviation As of 04:58 am pdt Saturday... Depth of the marine
layer varies around 1500-2500 feet across the area this morning.
Southerly gradient has held steady at around 1 mb with light
southerly winds in the valleys such as at ksjc and ksns. CIGS are
higher than previous mornings with ifr to MVFR along the coast and
sf bay as well as the north bay valleys whileVFR continues
inland. Stratus should begin to retreat to the coast after sunrise
withVFR developing at all TAF sites by late morning. Winds this
afternoon turning onshore and increasing to 10-15 kt. Stratus will
likely impact similar locations tonight with lower CIGS as high
pressure compresses the marine layer.
Vicinity of ksfo... Stratus rapidly filling in near the terminal
and approach with MVFR CIGS at times through 16-17z. Stratus may
be patchy through the morning especially if any light
southwesterly winds mix down to the surface.VFR this afternoon
with winds increasing to near 15kt.
Sfo bridge approach... Similar to ksfo.
Monterey bay terminals... Ifr CIGS this morning withVFR developing
around 17-18z. Ifr CIGS returning early to mid evening tonight.
Marine As of 02:53 am pdt Saturday... Light northerly winds will
persist over the northern outer waters while light southwesterly
winds will develop elsewhere through the weekend. Steep, short
period northwesterly swells will continue to decrease through the
weekend with period becoming 7 to 8 seconds. Moderate period
southerly swells will increase to 2 to 3 feet on Sunday and
persist through early next week with light moderate period
northwesterly swell continuing through the period.
Mtr watches warnings advisories
Tday Sca... Sf bay from 12 pm
public forecast: rww
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Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
|Stations||Dist||Age||Wind||Air Temp||Water Temp||Waves||Pressure||DewPt|
|46092 - MBM1||6 mi||57 min||SE 3.9||59°F||58°F||1012 hPa (+0.3)|
|MLSC1 - Moss Landing, South Harbor, CA||12 mi||63 min||S 2.9 G 8||60°F||1012.5 hPa (-0.0)||58°F|
|ELXC1 - Elkhorn Slough Reserve, CA||14 mi||82 min||ESE 1||60°F||1011 hPa||58°F|
|46240 - Cabrillo Point, Monterey Bay, CA (158)||15 mi||37 min||61°F||2 ft|
|MEYC1||17 mi||91 min||62°F||1012.3 hPa|
|46114 - West Monterey Bay, CA||20 mi||37 min||61°F||5 ft|
|46042 - MONTEREY - 27NM West of Monterey Bay, CA||21 mi||77 min||7.8 G 12||60°F||61°F||6 ft||1011.6 hPa (+0.3)|
|46239 - Point Sur, CA (157)||34 mi||37 min||60°F||6 ft|
|RTYC1 - 9414523 - Redwood City, CA||48 mi||55 min||WNW 2.9 G 4.1||64°F||76°F||1012.4 hPa|
Wind History for Monterey, CA(wind in knots) EDIT (on/off)  Help
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Watsonville, Watsonville Municipal Airport, CA||14 mi||74 min||NNW 3||10.00 mi||Partly Cloudy||60°F||55°F||86%||1012.2 hPa|
|Monterey Regional Airport, CA||19 mi||73 min||N 0||10.00 mi||Overcast||63°F||55°F||78%||1013.6 hPa|
|Salinas, Salinas Municipal Airport, CA||24 mi||74 min||SE 4||10.00 mi||Overcast||62°F||57°F||84%||1013 hPa|
Link to 5 minute data for KWVI
Wind History from WVI (wind in knots)
|1 day ago||Calm||Calm||Calm||Calm||SW||S||S||S||S||S||S||SE||E||Calm||Calm||S||SE||NE|
|2 days ago||Calm||Calm||S||SW||SW||S||S||S||S||S||SE||E||Calm||SE||E||E |
EDIT Weekend mode (on/off) (on/off)  Help One Week of Data
EDIT (on/off)  Help One Week of Data
Weather Map and Satellite Images(on/off)  HelpWeather Map
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 (8,2,3,4)(on/off)  Help
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