921 
fxus66 khnx 212304 
afdhnx 


Area forecast discussion 
National Weather Service San Joaquin Valley - Hanford California 
304 PM PST Sat Nov 21 2009 


Synopsis... 
mostly clear throughout the area tonight with the exception of 
low clouds due to upslope winds over the foothills near the Sierra 
Nevada and mountain areas of Kern County. High pressure will 
return with dry conditions and gradually warming temperatures 
Sunday through the Holiday weekend. 


&& 


Discussion... 
impressive system moving into Pacific northwest tonight and will have no 
impact on the areas weather. Clouds have remained banked along 
the east side of the valley along the Sierra foothills all day 
with low clouds...fog...and drizzle. The rest of the forecast area 
has cleared out quite nicely. 


Models are producing some patchy fog in some the fog prone areas 
along the 198 corridor...this is also where the coldest temperatures are 
expected as well...with some patchy frost in sheltered areas. 


Zonal flow on Sunday will give way to a gradual ridge building in 
over the area through Thanksgiving...with warming temperatures and 
clears skies expected. Another short wave trough with little or no 
moisture will approach the region by Friday with an increase in 
clouds across the northern portion of the San Jose valley. 


Confidence is good through Friday as the extended models are in 
decent agreement with the longwave pattern. 


&& 


Aviation... 
low clouds are continuing to make an impact across the southern 
Sierra and the Tehachapi Mountains. Clouds have been scattering out 
in the Fresno County portion and further north for the Sierra but 
have been persistent in the Tulare County portion. Further south the 
low clouds are having a tough time decreasing. We received a report 
of a motorist in Sequoia North Atlantic park who experienced near zero visibility in 
fog at about 3kft. The low clouds will probably not erode much 
overnight in the Kern Mountains with another shot of cool air 
expected to move south into the valley. Gusty winds across the San 
Joaquin Valley will diminish this evening. Areas of fog are expected 
to form later tonight across portions of the valley. Have brought 
LIFR conditions to kvis and IFR conds for visibility to other terminal 
sites late tonight and early Sunday. Low clouds and fog will 
continue overnight across the far southern valley and Tehachapi 
Mountains with LIFR conditions there at times through 12z Sunday. 


&& 


Air quality issues... 
none 


&& 


Hnx watches/warnings/advisories... 
none. 


&& 


$$ 


Public...jdb 
AVN/fw...Brotherton 


Weather.Gov/Hanford