Area forecast discussion
National Weather Service San Francisco Bay area
902 PM PDT Tuesday may 21 2013
Discussion...as of 9:00 PM PDT Tuesday...an upper level low moved
into the Pacific northwest today bringing a much cooler airmass
to the area. Highs inland were 15-20 degrees cooler than
yesterday while highs were 5-10 degrees cooler near the coast.
Cool advection resulted in increased winds over mainly the north
and East Bay and near the coast with winds 20-30 knots gusting as
high as 45 knots.
The upper low will continue over the Pacific northwest through
Thursday. Temperatures may drop a few more degrees Wednesday and
Thursday as the low shifts slightly south. With the cool air in
place the airmass will stabilize and winds are expected to drop
off by Wednesday. However winds may pick up some on Thursday
afternoon as a vorticity center rotating around the upper low moves
through the area.
The upper low will shift northeast on Friday resulting in slightly
warmer temperatures. But temperatures will continue to be below
normal as another upper trough follows closely behind the low and
moves towards the Pacific northwest Saturday. The Memorial Day
weekend is shaping up to be cool though temperatures should be a
little warmer on Memorial Day.
&&
Aviation...as of 6:26 PM PDT Tuesday...mainly clear skies are
expected through tonight as tight gradients maintain strong winds
across the region. Gusty winds will persist through this evening
with lighter winds anticipated during the overnight hours. Strong
and gusty winds will return to the region by Wednesday afternoon.
Vicinity of ksfo...VFR. Strong and gusty west winds sustained at
around 30 knots with gusts as high as 45 knots this afternoon. Airport
weather warning in effect through 9 PM this evening.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR. Gusty west winds through late
tonight.
&&
Mtr watches/warnings/advisories...
... Reyes to Pigeon pt 0-10 nm
Small Craft Advisory...Pigeon pt to pt pinos 0-10 nm
glw...pt Arena to Pigeon pt 10-60 nm
glw...pt pinos to pt Piedras Blancas 0-10 nm
glw...Pigeon pt to pt Piedras Blancas 10-60 nm
Small Craft Advisory...pt Arena to pt Reyes 0-10 nm from 3 am
glw...pt Arena to pt Reyes 0-10 nm until 3 am
Small Craft Advisory...sf Bay until 3 am
Small Craft Advisory...mry Bay until 3 am
&&
$$
Public forecast: west pi
aviation/marine: CW
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