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fxus66 khnx 111641 
afdhnx 


Area forecast discussion 
National Weather Service San Joaquin Valley - Hanford California 
941 am PDT Sat Oct 11 2008 


Update... 
colder but clear and dry conditions across the region this morning. 
Some clouds along the higher elevations of the Sierra north of Kings 
Canyon but no shower activity on radar at this time. Strong north jet on back 
side an upper low should provide breezy to windy conditions across 
the San Joaquin Valley today. The Oakland and vandenberg soundings 
indicate low level instability to around 7kft and strong north low 
level winds averaging about 30 knots. The stronger momentum wind 
should easily mix down to the surface this afternoon especially 
over the central and the west side of the San Joaquin Valley. 
Expect some instability snow showers to develop this afternoon 
mainly over the high elevations of the Sierra. Weather concern 
will shift from strong winds to cold temperatures tonight. No 
changes to going forecast. 


&& 


Previous discussion... 
large scale closed upper low over Nevada at this time is expected to slowly 
kick out to the northeast by Monday. Gradients have dropped off 
and winds are not expected to be as strong today as they have 
been over the past couple of days. However...they will still be a 
bit gusty at times along the west side of the valley and into the 
Kern County mountains and desert. Temperatures will be the main 
forecast problem through the period. The biggest short term concern 
will be near record low temperatures on Sunday morning. Daytime maximum temperatures 
will be continue to be around 10 to 15 degrees below normal 
through Monday over the valley. 


The GFS and European model (ecmwf) are not in agreement concerning the extended. 
The GFS is more zonal and flat with the epac ridge expected to 
build in by midweek next week and the European model (ecmwf) is more amplified with 
the epac ridge and heights are around 60dm higher by Wednesday. Needless 
to say this is bearing a significant problem with the forecast 
temperatures from midweek into the weekend. Local verification has 
indicated that the ecmwfbc guidance is the best performer in the 
extended and has been notably a better forecast guidance for 
temperatures for the County Warning Area. We have consistently been seeing the 
ecmwfbc out perform the mosguidebc and the gfs40bc temperature 
guidance. So with that being said will lean more with the European model (ecmwf) 
solution and blend towards the HPC and persistence forecast for the 
temperatures. This will still bring US well above normal by the 
end of the week for the valley locations and into the desert area. 
The GFS was introducing some clouds on Friday but has backed off 
that solution and will leave alone for now. 




&& 


Aviation...VFR conditions expected across the district through 12z 
Sunday. 




&& 


Air quality issues... 
none 


&& 


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


$$ 


Public...mv 
AVN/fw...Bingham 


Weather.Gov/Hanford