Scientific Forecaster Discussion
fxus66 kmtr 272158
Area forecast discussion
National Weather Service San Francisco Bay area
158 PM PST Mon Feb 27 2017
Synopsis... dry weather will return by tomorrow for our entire
area. Dry conditions will then persist through the end of the
work week, along with a warming trend. A system moving into the
Pacific northwest this upcoming weekend may produce light rain
especially on Sunday.
Discussion...as of 2:00 PM PST Monday...chilly day across our
region today with many spots only in the lower to mid 50s. Kmux
radar has indicated a few showers through the day today --
generally in Monterey and San Benito counties. Amounts have been
light for the locations that have had any tips of the bucket.
Tonight and Tuesday night will be the coolest for the week as cool
air aloft combined with fairly light winds, weak offshore flow and
light winds at the surface will allow for temperatures to drop
back into the 30s. Patchy frost will also be possible.
All signs continue to point to a substantial change in the
pattern as a ridge of high pressure builds into our region by the
middle of the week. Temperatures will warm back into the 60s for
some locations on Wednesday and most urban areas for Thursday and
Friday. Still looks like an outside shot of a lower 70 in Monterey
and san bentio counties. The ridge will flatten out on Saturday
which will lead to minor cooling.
Models are starting to trend wetter for Sunday as a longwave
trough will near the coast. GFS over the past couple of runs has
been fairly bullish with amounts and coverage while the other
models have kept more of the activity to the north with just light
amounts going through our County Warning Area. 12z European model (ecmwf) operational run does show
light rain down to slo County along with the GFS ensemble mean.
Pops were slightly increased and will be increased again tonight
if that trend continues.
Longer range outlook for next week does favor warmer than normal
temperatures along with drier than normal conditions.
Aviation...as of 10:00 am PST Monday...for 18z tafs. Widespread
VFR expected today with a few vcsh off the coast and over
southern Monterey/San Benito counties. Cumulus development will
predominately be vertically limited and over the higher terrain.
Vicinity of ksfo...VFR. Northwest-west winds generally 15kt or less.
Sfo bridge approach...similar to sfo.
Monterey Bay terminals...VFR. Northwest-west winds generally 11kt or less.
Marine...as of 09:57 am PST Monday...gradually increasing
northwest winds this afternoon through tonight then weakening
tomorrow... except along the Big Sur coast where breezy winds
will continue. Northwest winds will increase to become moderate
again Thursday through Friday. A moderate northwest swell will
move through the waters this week.
... Pt to pt pinos 0-10 nm
Small Craft Advisory...pt Arena to Pigeon pt 10-60 nm from 9 PM until 3 am
Small Craft Advisory...pt pinos to pt Piedras Blancas 0-10 nm
Small Craft Advisory...pt 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 Piedras Blancas 10-60 nm
Small Craft Advisory...mry Bay until 9 PM
Public forecast: Bell
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