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000 
FXUS66 KMTR 200349
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
849 PM PDT Thu Apr 19 2018

.SYNOPSIS...Dry and warmer weather are forecast into the upcoming
weekend. A weak cutoff low approaches the region mid to late next
week.

&&

.DISCUSSION...As of 8:50 PM PDT Thursday...An upper level low 
over southern Nevada and upper level ridge off the California 
coast brought a cool northerly flow to the district. Temperatures 
were generally 3 to 5 degrees warmer than yesterday but still 
slightly below normal. Additional warming is expected the next two
days as the low moves east and the ridge moves over the district.
The northerly breeze will decrease as well. By Saturday 
temperatures should warm up to the mid to upper 60s at the coast 
and the low to mid 80s inland.

A weak upper trough will pass north of the area Sunday bringing a
halt to the warming but temperatures will still be about 5 degrees
above normal. This is expected to last into the beginning of next
week. 

Medium range models form a cutoff low off the California coast the
middle of next week. The positions of cutoff lows are hard to
predict as different models and model runs place the low in 
different positions. But there is agreement in the latest runs in
bringing the low close enough to the Bay Area to bring a chance of
precipitaion. Any precipitation will be of the scattered showers 
variety. Again...cutoff lows are hard for the models to get a 
grasp on so until then confidence remains low.

&&

.AVIATION...As of 4:52 PM PDT Thursday...For 00z tafs. Patchy low
clouds across area hill this afternoon will dissipate this evening
after sunset. Patchy low clouds will return to KMRY and KSNS after
a temporary clearing this afternoon. Elsewhere mainly clear skies
expected. Gusty onshore flow will persist through late this
afternoon and ease after sunset. 

Confidence is moderate to low with respect to overnight cigs. 

Vicinity of KSFO...VFR will prevail through the forecast period. 
Afternoon west winds to around 20 kt, with gusts over 25 knots 
will ease after 04z.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR cigs anticpated to return to KMRY
around 04z this evening. KSNS is anticipated to see temporary
clearing with cigs also returning around 04z. Gusty west winds
around 15 kt with gusty to around 25 kt expected through this 
afternoon. Winds will ease this evening.

&&

.MARINE...as of 2:49 PM PDT Thursday...High pressure over the 
eastern Pacific will maintain breezy/gusty NW winds through Friday
and into the weekend. As a result, the strong winds will generate
steep wind waves and fresh swell, causing hazardous seas through 
much of the weekend.

&&

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

&&

$$

PUBLIC FORECAST: W Pi
AVIATION: CW
MARINE: BAM

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