Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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FXUS66 KMTR 210028
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
428 PM PST Wed Feb 20 2019

.SYNOPSIS...Lingering showers will continue over the region
through late this evening, especially over the Central Coast and
East Bay Hills with snow showers in elevations generally above
3,500 feet. Dry conditions develop on Thursday and persist into
Friday before rain returns to northern California during the
weekend and into early next week.

&&

.DISCUSSION...as of 01:39 PM PST Wednesday...Isolated showers
will continue over the Central Coast and out over the coastal
waters through this afternoon. Seeing some showers on radar in far
eastern Napa County as well that will slide down into the East
Bay and then forecast to push into Santa Clara, Monterey and San
Benito Counties through early this evening. Overall, rainfall
amounts are generally a few hundredths to one- tenth of an inch
with each passing showers. Given the cold air mass aloft, small
hail will also be possible within the heavier showers and snow is
likely occuring in elevations at or above 3,500 feet. Lingering
showers look to potentially continue over the mountains above the
Big Sur Coast into Thursday morning. Otherwise, showers will
tapper off late this evening and tonight across much of the region
as the short-wave disturbance exits.

Sky conditions will clear late tonight into Thursday with
temperatures again turning colder. Look for more widespread 30s for
inland areas and lower 40s near the coast on Thursday morning.
Daytime temperatures will warm into the 50s for most urban locations
while areas in the hills/higher elevations will be slightly cooler.
This trend will continue into Friday with ongoing dry conditions as
a weak short-wave ridge develops.

The forecast models are converging in their solutions heading into
the weekend with increasing chances of precipitation over northern
California. At this time, the best chance for rainfall will be over
far northern Sonoma and Napa Counties Saturday morning and then
southward to around the Golden Gate by the afternoon/evening. Most
areas south of San Francisco look to remain dry through this period.
Rain chances potentially shift southward on Sunday and linger across
the region during the first part of next week. However, the best
chances for widespread rainfall look to stay over the northern
portion of the region. If even a weak atmospheric river takes aim at
the North Bay late in the forecast period, the potential for
flooding concerns would greatly increase. Folks are urged to monitor
the forecast in the coming days.

Looking out a bit further, longer range guidance suggest an
unsettled pattern with potential for widespread rainfall over the
region heading into the beginning of March. The CPC has our entire
region depicted in a 50% probability of above normal precipitation
from February 28th - March 6th. Stay tuned...the winter season
continues.

&&

.AVIATION...As of 4:25 PM PST Wednesday...Mostly SCT clouds with
cigs and showers confined to the higher terrain. VFR conditions
expected over the terinals with showers remaining in the vicinity
through the evening hours. Gusty westerly winds to 25-30 kt
through late tonight.

Vicinity of KSFO...VFR. Showers in the vicinity through 04Z.
West winds gusting to 30 kt decreasing to 25 kt after 04Z.
Winds decreasing further after 12Z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals....Gusty northwest winds will keep VFR
conditions. A few showers in the vicinity over the waters and the
hills. Winds gusting to 30 kt through the Salinas Valley and 25 kt
near Monterey Bay decreasing after 04Z.

&&

.MARINE...as of 04:12 PM PST Wednesday...Northwest winds are
expected to increase into this evening and  remain gusty through
the rest of the work week. Widespread gale  force conditions are
forecast across the outer waters starting  late tonight and
lasting through Thursday. Isolated gale force  gusts will also be
possible along the coast. Gusty winds will  generate steep fresh
swell causing hazardous conditions,  especially for smaller
vessels. Moderate northwest swell will  continue through the end
of the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Reyes to Pigeon Pt 0-10 nm
             SCA...Pigeon Pt to Pt Pinos 0-10 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
             SCA...Pt Arena to Pigeon Pt 10-60 nm until 3 AM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm until 3 AM
             GLW...Pt Arena to Pigeon Pt 10-60 nm from 3 AM
             GLW...Pigeon Pt to Pt Piedras Blancas 10-60 nm from 3 AM
             SCA...SF Bay until 9 PM
             SCA...Mry Bay until 9 PM

&&

$$

PUBLIC FORECAST: RGass
AVIATION: W Pi
MARINE: AS

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