Area Forecast Discussion


303 
FXUS66 KMTR 112211
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco Bay Area
211 PM PST Mon Dec 11 2017
.SYNOPSIS...Strong high pressure will remain in place through much 
of the week and result in dry weather conditions along with above 
average daytime temperatures. Clear skies and weak offshore flow 
will allow for cool overnights which will warm slightly late in the 
forecast period as onshore winds return.
&&
.DISCUSSION...as of 01:49 PM PST Monday...A strong ridge of high 
pressure continues to dominate the weather pattern across the 
entire West Coast and will do so through much of the forecast 
period. This has resulted in continued dry weather conditions and 
above average temperatures. Meanwhile, upper level flow will 
continue to advect smoke from wildfires over southern California 
today and potentially into tomorrow as well. While some smoke will
be noticeable to the generally public, the heaviest concentration
of smoke will remain above the surface in the higher levels of 
the atmosphere. Look for afternoon temperatures to warm into the 
60s for the San Francisco Bay area and points northward while the 
South Bay down through the Central Coast will experience 
widespread 70s. 
A storm system is then forecast to approach the Pacific Northwest 
late in the week and will help to weaken the ridge slightly. This 
will allow for daytime temperatures to cool by a few degrees late in 
the week and into the upcoming weekend with a slight increase in 
overnight temperatures as onshore flow returns. Precipitation with 
this system will stay well to the north however with ongoing dry 
conditions for California. 
Longer range guidance suggest a potential change in the weather 
pattern sometime next week that might bring light precipitation to 
portions of the state. However, confidence is low at this time 
and will need to be monitored in the coming days. Until then, look
for ongoing dry weather conditions and above average daytime 
temperatures to persist.
&&
.AVIATION...As of 9:39 AM PST Monday...for 18Z TAFs. Upper level
winds continue to bring smoke from the Southern California fires
northward across the forecast area resulting in a broken to
scattered cloud deck around 20K to 25K feet. This smoke layer will
persist through much of the day then hopefully clear out
overnight. Otherwise VFR conditions and light winds will prevail.
Patchy fog and low clouds will return tonight over KSTS. 
High Confidence. 
Vicinity of KSFO...VFR. Light offshore winds expected through the
forecast period. 
SFO Bridge Approach...Similar to KSFO.
Monterey Bay Terminals...VFR. Generally light offshore winds. 
&&
.MARINE...as of 2:10 PM PST Monday...Light to moderate winds will
continue along the Central Coast as high pressure remains over 
the region. Winds will gradually increase out of the north 
midweek. A longer period swell arrived today and will impact the 
coast thru midweek.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...NONE.
&&
$$
PUBLIC FORECAST: RGass
AVIATION/MARINE: CW
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