Area forecast discussion 
National Weather Service San Joaquin Valley - Hanford California 
312 PM PDT Friday may 24 2013 


Synopsis... 
low pressure over the Pacific northwest is bringing a cool onshore 
flow to the central California interior. Temperatures will remain 
near normal through early next week. Increased chances for light 
rain showers in the San Joaquin Valley and mountain areas on Memorial 
Day. 


&& 


Discussion...cool dry conditions Omega block pattern continues 
across the US as large closed low center remains nearly stationary 
over the Pacific northwest. Additional disturbances will move through the low 
during the weekend maintaining the trough and onshore flow into 
central California. This will result in cool dry conditions across central 
California for much of the weekend. A stronger disturbance will 
push through Sunday increasing onshore grads across central California 
Sunday afternoon with breezy conditions below the mountain passes 
of the Kern County mountains and desert. 


A stronger trough is expected to move through the area late Monday 
and Tuesday. The ecm is deeper and further S with the low center 
as it dives south towards scal. The ecm is also significantly 
wetter than the GFS. The 12z operational models are in poor 
agreement atmosphere. However the ensemble means of ec and GFS remain in 
reasonable agreement. At the moment will be taking a blend of the 
two ensemble means. Satellite images show a fetch of subtropical 
moisture with the weather system S of the Aleutians prognosticated to 
move through central California Monday night and Tuesday. Models indicate 
precipitable waters  of 1-2 Standard deviations above normal across central California 
Monday night. Temperatures at 10kft drop to -2c by Tuesday 
morning. This could lower the snow level to near 8kft with some 
snow accumulations over the Sierra. Breezy to windy conditions 
will develop Monday afternoon and Tuesday especially in the Kern 
County mountains and desert area. 


The trough moves through pretty quick and keep US in a strong northwest 
flow through next week which will keep the temperatures in check as cool 
onshore flow will prevail. 


Aviation... 
VFR conditions will prevail across the central California interior. 


&& 


Air quality issues... 
none. 


&& 


Certainty... 


The level of certainty for days 1 and 2 is high. 
The level of certainty for days 3 through 7 is low. 


This information is provided as part of a trial project conducted 
by the National Weather Service San Joaquin Valley - Hanford. 
Certainty levels include low...medium...and high. Please visit 
www.Weather.Gov/hnx/certainty.Php /all lower case/ for additional 
information and/or to provide feedback. 


&& 


Climate... 
records 
site date hi_max:year lo_max:year hi_min:year lo_min:year 


Kfat 05-24 103:1943 64:1916 68:2001 41:1953 
kfat 05-25 102:1890 59:1906 68:1890 42:1980 
kfat 05-26 103:1974 66:1946 68:1951 40:1953 


Kbfl 05-24 107:1982 68:1980 76:1982 41:1916 
kbfl 05-25 106:1982 58:2008 77:1982 39:1893 
kbfl 05-26 107:1951 68:1998 72:1979 40:1918 
&& 


Hnx watches/warnings/advisories... 
none. 
&& 


$$ 


Public...mv 
AVN/fw...Molina 
synopsis...andersen 


Weather.Gov/Hanford