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fxus66 kmtr 281746 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
1046 am PDT Tue Mar 28 2017

Synopsis...a ridge of high pressure will build into our region
and provide warmer weather the next couple of days. At the same
time locally breezy northwesterly winds will continue. Cooler
conditions are likely on Thursday as a system moves through
northern California. The ridge will rebuild by the end of the
week leading to another increase in temperatures.

&&

Discussion...as of 08:25 am PDT Tuesday...quiet weather
conditions prevail over the region this morning as high pressure
builds over the eastern Pacific. Aside from a slight increase in
high level clouds, mostly sunny conditions will prevail today
across the region along with warmer temperatures. The ongoing
forecast remains on track and no updates are needed at this time.

&&

Previous discussion...as of 3:00 am PDT Tuesday...although temperatures
will be warmer today as a ridge of high pressure builds into our
region, it won't feel very warm as breezy northwesterly conditions
can be expected from later this morning to the evening. In fact,
surface gradients are still impressive at this hour with sfo-acv
at 5.5 mb. Winds of 15 to 25 mph can be expected in most spots
with local gusts over 30 mph likely. Temperatures will generally
be in the 60s to lower 70s at the coast with 70s inland.
Temperatures will see another 3 to 5 degree increase in most spots
for Wednesday as 925 mb values increase another 2c.

On Thursday an inside slider will move from northern California
down into Nevada. Due to the track virtually all of the showers
should stay to our north and east. However, models do keep the
outside shot of light rain hitting higher elevation locations.
Kept a few mentions of pops around 20% for those spots. Bigger
impact will be another round of breezy conditions followed by
cooler temperatures. Highs will drop back into the upper 50s to
the upper 60s.

The ridge will rebuild and move back to our region starting on
Friday and continuing into the weekend. Some disagreement between
the models as far as how much warming will occur. European model (ecmwf) is running
3 to 7 degree warmer than the GFS. Based on its better
verification, the forecast was nudged toward the higher values.

Longer range guidance favors dry conditions through at least the
middle of next week. Some signs after that we will flip back to a
wetter pattern.

&&

Aviation...as of 10:33 am PDT Tuesday for 18z tafs. Current vsbl
satellite imagery shows few-sct high clouds over the region.
Expect this to be the case through the day. Biggest story will be
the winds today. West/northwest winds will pick up and become
gusty in the next hour or two. Winds won't be quite as gusty today
as yesterday, but will still gust 20-25 kt, locally higher,
through roughly about 03z (8pm pdt) at most terminals. Threw in a
chance of low clouds for the Monterey Bay terminals for Wednesday
morning. There could be a couple of hours of stratus around
sunrise, but confidence is low at this time. Overall, moderate to
high confidence with this forecast.

Vicinity of ksfo...VFR conditions anticipated. West to northwest
winds exceeding 20 to 25 kt possible through the evening, possibly
higher at ksfo.

Sfo bridge approach...similar to ksfo.

Monterey Bay terminals...VFR through the rest of the day. Tafs
reflect MVFR cigs around sunrise Wednesday morning, but should
lift by 16z, if cigs develop at all. Gusty west/northwest winds
by 21z (2pm pdt) this afternoon, around 20 kt, diminishing around
03z.



&&

Marine...as of 08:25 am PDT Tuesday...a long period northwest
swell...17 to 18 seconds...will move through the coastal waters
today. Moderate and gusty northwest winds will continue for the
next several days as a strong surface pressure gradient builds
over the region.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 0-10 nm
Small Craft Advisory...pt Reyes to Pigeon pt 0-10 nm
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm
Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm
Small Craft Advisory...rough bar advisory for sf bar
Small Craft Advisory...mry Bay from 1 PM

&&

$$

Public forecast: rgass
aviation/marine: bm



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