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000 
FXUS66 KMTR 201559
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
859 AM PDT Sun May 20 2018

.SYNOPSIS...A deep marine layer will allow for continued overnight
and morning clouds along the coast the next few days. Temperatures
will remain seasonably cool this week and into next weekend.

&&

.DISCUSSION...as of 8:59 AM PDT Sunday...Deep marine layer around
3000 feet this morning with clouds inundating most areas from SF 
southward. Clouds will be slow to clear with upper trough and 
continued onshore flow. Afternoon highs still below normal on 
average for inland areas with highs only in the 70s once the sun 
breaks out. 12z nam shows some more coastal drizzle tonight into 
early Monday morning with cyclonic flow aloft, deep marine layer 
and moist onshore flow. Upper trough will be slow to move over 
southern California Monday and Tuesday with the end result being 
continued below normal temperatures for the Bay Area with morning 
clouds followed by afternoon sunshine.

There may be some weak midweek upper ridging but the net result
wont be too much change in the sensible weather with daytime highs
generally 60s coast and 70s inland with very few sites reaching
the 80s this week, so overall trend of below normal.

Long range models indicate a stronger upper trough approaches for
Memorial Day weekend implying continued below normal temps.

&&

.AVIATION...As of 4:59 AM PDT Sunday...For 12z TAFs. Generally 
MVFR cigs across the region, per 11z surface obs. Fort Ord 
Profiler and fog product satellite shows a very robust and deep 
marine in place. The thick marine layer and the decent onshore 
gradient will likely keep stratus over all TAF terminals through 
the majority of, if not all, the day today. Perhaps some clearing 
possible at some terminals for a few hours in the afternoon. Winds
will be on the breezy/gusty today, into this evening, sustained 
around 15 kt by this afternoon, with gusts exceeding 20 kt at 
times. 

Moderate forecast confidence. 

Vicinity of KSFO...MVFR cigs through at least 20-21z, with the
possibility of not clearing at all. Westerly breezy/gusty winds 
will continue through the day and evening. 

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...Thick marine layer will likely keep
MVFR cigs over the Monterey Bay terminals all day/evening. Slight
chance of clearing at KSNS this afternoon, but not confident 
enough to include in TAF. IFR cigs possible by tonight. Breezy
onshore winds, occasionally gusty this afternoon and evening. 

&&

.MARINE...as of 08:49 AM PDT Sunday...A strong north to south
pressure gradient along the California coast will maintain
moderate to strong northwesterly winds over  the coastal waters
through Monday. As a result, steep wind waves  will produce
hazardous conditions for small crafts. A long period  southerly
swell will increase and mix with northwesterly swell by  Monday
morning, gradually increasing through much of the week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...SF Bay from 12 PM
             SCA...Mry Bay from 12 PM
             SCA...Pigeon Pt to Pt Pinos 0-10 nm from 12 PM
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Reyes to Pigeon Pt 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

&&

$$

PUBLIC FORECAST: RWW
AVIATION: RGass
MARINE: RGass

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