834 
fxus66 kmtr 211301 
afdmtr 


Area forecast discussion 
National Weather Service San Francisco Bay area California 
500 am PST Sat Nov 21 2009 


Discussion...as of 4:00 am PST Saturday...skies are mostly clear in 
the wake of the cold front that passed across the district yesterday 
and last night. With clear skies...light winds...and a moist 
ground...fog has formed in many of the interior valleys of the 
district. Fog is being reported from the North Bay south through the 
East Bay...Santa Clara Valley...Hollister Valley...and down the 
Salinas valley. At times visibilities have dropped to one quarter 
mile at spots. Temperatures this morning are in the 30s and 40s. 


Weak shortwave ridging will bring dry weather to the district today 
and this evening...along with cool temperatures. A shortwave near 47/147 
will move rapidly...buoyed by a 135 knots jet per GOES high density 
winds...to the Pacific northwest coast late tonight into Sunday. The 
district will be in the southern end of the associated cold front. 
Therefore...have mentioned a chance/slight chance of showers for the North 
Bay late tonight and Sunday. 


Medium range models are in agreement in building a ridge along the 
California coast for the beginning and middle of next week. This will 
result in dry weather along with above normal temperatures. The ridge will 
flatten on Thanksgiving as a shortwave moves to the Pacific northwest. As of 
now...the main affect on the districts weather will be some clouds 
and cooler temperatures. However...it will remain dry through the end of the 
week with near normal temperatures Thanksgiving day and Friday. 


&& 


Aviation...as of 5:00 am PST Saturday...scattered high clouds and 
patchy ground fog is expected this morning in the wake of the front 
that passed yesterday. Skies are expected to clear later this 
morning with transient high clouds continuing to pass overhead. 


Vicinity of ksfo...VFR conditions through tonight with only passing 
high clouds expected. West winds under 10 knots will continue through 
tonight. 


Ksfo bridge approach...same as ksfo. 


Monterey Bay terminals...patchy ground fog vicinity ksns otherwise VFR 
conditions expected through tonight. Light west winds expected. 


&& 




Mtr watches/warnings/advisories... 
... For hazard seas pt Arena to Pigeon pt 10-60 nm until 2 PM 
... Pigeon pt to pt Piedras Blancas 10-60 nm 
... Pt pinos to pt Piedras Blancas 0-10 nm 
... Starting 1 PM Pigeon pt to pt pinos 0-10 nm 
... For rough bar conditions until 2 PM 


$$ 


Public forecast: mhs 
aviation/marine: CW 


National Weather Service on the web at weather.Gov/sanfrancisco