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fxus66 kmtr 221813 
afdmtr

Area forecast discussion
National Weather Service San Francisco Bay area
1013 am PST Wed Feb 22 2017

Synopsis...a few lingering showers will be possible today into
early Thursday morning, mainly offshore and near the coast.
Otherwise, drier and much cooler conditions are forecast through
late week with chilly overnight/morning temperatures. Unsettled
weather conditions return by the weekend with the potential for
widespread rain and gusty winds.

&&

Discussion...as of 9:51 am PST Wednesday...radar scans continue
to pick up a few showers just off the San Mateo coast. Expect
these to continue this morning, but mainly along and near to the
coast. Mostly dry conditions are expected elsewhere. Cooler
daytime temperatures are expected today with our cooler and drier
airmass, with high temperatures only in the low to mid 50s in the
lower elevations and 40s more common in the hills. Similar
conditions are anticipated through Thursday along with an isolated
shower or two late tonight into early Thursday morning as a weak
weather system drops southward along the coast. The best chance
for any showers will be over the coastal waters and along the
coastal ranges while inland areas will likely remain dry through
Friday.

The cooler and drier air mass settling into the area along with
lighter winds will allow for some chilly overnight/morning
temperatures, especially in inland valleys. Low temperatures will
likely fall into the 30s, even upper 30s to near 40 near the
coast. Inland, wind sheltered areas can expect a period of sub
freezing temperatures both late tonight/Thursday morning and again
Thursday night/Friday morning. With this too, patchy frost will be
possible in the coldest, inland valley locations.

Forecast models continue to show another storm system slated to
affect the district this weekend. Latest model runs, however, are
trending to a less-wet northwest flow pattern and cold upper low
moving across the area, without the connection to the moist,
subtropical tap. The 12z run of the GFS is now more in line with
last night's European model (ecmwf) run that indicated this scenario. The district
will likely see cold showers moving across, but latest rainfall
estimates are not much more than a half inch. Will continue to
monitor the forecast runs and see how this progresses. Folks are
urged to stay up-to-date with the latest forecast as we fine tune
details for the upcoming weekend.

&&

Aviation...as of 10:15 am PST Wednesday...for 18z tafs.
Widespread VFR today. Breezy to occasionally gust onshore winds
through midday and into the evening. Unstable air mass will
contribute to cumulus development between 3000-5000 ft today with
some vcsh or brief -shra possible. Can not rule out an isolated
thunderstorm over the North Bay. Winds weaken tonight with patchy
dense fog posbl for North Bay vallies overnight.

Vicinity of ksfo...mainly VFR. Breezy onshore winds, gusty by
afternoon hours, ranging 10-20 kt with gusts up to 25 kt. Winds
decrease late tonight or early Thursday morning.

Sfo bridge approach...similar to sfo.

Monterey Bay terminals...mainly VFR today. Moderate and gusty
onshore winds by early afternoon.

&&

Marine...as of 10:07 am PST Wednesday...increasing northwesterly
winds today and tomorrow. Winds turn light and variable on
Friday. Winds shift to become southerly and increase later
Saturday into Sunday. The northwest swell will gradually taper
off in strength through the coming days. Hazardous conditions
from squared seas will exist in portions of the coastal waters
through the coming days as well.

&&

Mtr watches/warnings/advisories...
... Pt to pt pinos 0-10 nm from 2 PM
Small Craft Advisory...Pigeon pt to pt Piedras Blancas 10-60 nm from 2 PM
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...rough bar advisory for sf bar
Small Craft Advisory...mry Bay from 2 PM

&&

$$

Public forecast: Sims
aviation: drp
marine: drp



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