Marine Weather and Tides
5/20/2018 -- NOAA is having problems with the data feed that I use to draw the graphs. They are aware of the issue and working to resolve it. Sometimes changing the location by about a mile will give a correct graph. 3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
|Sunrise 5:48AM||Sunset 8:36PM||Sunday June 24, 2018 9:32 AM PDT (16:32 UTC)||Moonrise 4:48PM||Moonset 2:53AM||Illumination 86%|
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7 Day Forecast for Marine Location Near Point Arena, CAHourly EDIT Help
Area Discussion for - San Francisco/Monterey Bay Area, CA  (on/off)  Help NOTE: mouseover dotted underlined text for definition
|Fxus66 kmtr 241524|
area forecast discussion
national weather service san francisco bay area
824 am pdt Sun jun 24 2018
Synopsis A cooling trend will continue to take hold of the bay
area today into Monday. The red flag warning remains in effect for
the north and east bay hills today. The pattern will return to a
more seasonable or cooler set up for the work week.
Discussion As of 08:24 am pdt Sunday... The southerly surge
that raced up the coast yesterday brought widespread clouds along
the coast and locally inland, especially down the salinas valley.
Fort ord profiler shows the marine layer of just a few hundred
yesterday to near 2,000 feet this morning. There have also been a
few reports of patchy fog with drizzle this morning. Latest
satellite trends on visible imagery does show some thinning on the
edges of the marine layer, but doe expect clouds to lingering
along the coast for much of the day. Given the southerly flow it's
totally possible that monterey clears out and santa cruz
struggles to see the Sun today.
The bigger story today, as noted on the previous discussion, will
be the widespread cool down. Still looking for a 10 to 20 degree
cool down across the interior. Despite the cool down temperatures
across the interior will be still be a few degrees above normal
with highs in the 80s and 90s. Far interior of napa, monterey and
san benito counties may see a few pockets of 100 deg.
No update is planned at this time.
Prev discussion As of 04:00 am pdt Sunday... The story for today,
Sunday, is a noticeable cool down across the bay area and
monterey bay regions. This is a result of the upper ridge axis
shifting to the east with an upper trough pushing in from the
west. A surge of winds from the south with low clouds and fog
began moving in yesterday evening as the ridge shifted while the
upper low is helping to pull the surge northward. As the upper low
moves closer to the coast the low clouds will deepen causing
deeper inland penetration under the influence of a strong onshore
push. In areas where the surge has already reached, temperatures
are 10 to 20 degrees lower than 24 hours ago with winds from the
south at 10 to 20 mph. This surging marine layer is deepening as
well, causing cooling temps inland by about 5 degrees. The lone
hold outs of warmer temps are the highest sites in the hills which
are still holding on to the 70s and 80s.
The forecast for the rest of the day is onshore flow and cooling.
Some areas will see a 10 to 20 degree cool down from the high
temps of Saturday. Inland regions will remain hot today before the
onshore flow really takes hold. Temps into the 90s will persist
and near 100 in portions of north and east bay, as well as parts
of san benito county. Offshore winds in the mountains and hills
will turn onshore through the day. In short, look for much cooler
temps than yesterday under the influence of onshore flow.
Several upper troughs will clip the region from the north through
the remainder of the week, keeping a cap on temps. At this time
it looks like the area will be seasonable or below normal through|
the week. These troughs will maintain a deep marine layer each
Aviation As of 4:43 am pdt Sunday... Southerly stratus surge
has advanced up past the mendocino sonoma county border, and is
already pushing through the san francisco bay into the delta as
well. Stratus has also filled into the salinas valley and into
san benito county. The marine layer depth is 2000 feet deep per
the fort ord profiler, and the sfo-sac surface pressure gradient
is up to 3.3 mb. Ceilings at mry and sns will be slow to clear
today, and look for bay area terminals to sock in overnight
tonight. Gusty westerly northwesterly winds are expected through
Vicinity of ksfo... Should remainVFR today but confidence is low.
Northwest winds will pick up this afternoon with gusts to 22
knots. Ifr CIGS developing by 08z.
Sfo bridge approach... Similar to ksfo.
Monterey bay terminals... Ifr CIGS through the morning. Look for
MVFR CIGS in the afternoon with gusty northwest winds to 20 knots.
Ifr CIGS again by 06z.
Fire weather As of 4:00 am pdt Sunday... Red flag warning
remains intact for the time being. Onshore flow, cooling temps,
and rising humidity will continue to develop through the day. That
said, overnight recoveries have been modest at best with rhs at
elevation in the 20-30% range. Valley to midslope recoveries have
been much better overnight, reaching into the 60-70% range. Winds
at elevation remain breezy this morning with diablo the big winner
at around 30 mph from the nnw. The red flag warning will need to
be reevaluated later this morning to determine how deep the marine
layer is developing. This may truncate the warning and allow it to
be cancelled early.
With the ongoing fire activity around the state and conditions
slowly changing will leave the red flag warning out for now.
Marine As of 03:11 am pdt Sunday... High pressure over the
eastern pacific and a thermal trough over inland california will
keep gusty northerly winds across the northern coastal waters
through today. Gusty winds will generate steep wind waves
creating hazardous sea conditions, particularly for small
vessels. Winds will subside tonight as a southerly surge pushes
northward shifting the winds along the inner coastal waters out
of the south. Winds will pick up again on Monday as an upper
trough moves through to the north.
Mtr watches warnings advisories
Tday Sca... Pt arena to pigeon pt 10-60 nm
sca... Pt reyes to pigeon pt 0-10 nm
sca... Sf bay
public forecast: mm
fire weather: rww
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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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