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fxus65 kpsr 202151 
afdpsr 


Area forecast discussion 
National Weather Service Phoenix Arizona 
245 PM MST Friday Nov 20 2009 


Synopsis... 
dry weather is expected to continue at least through Thanksgiving. 
The weak southern portions of Pacific low pressure systems will bring 
temperatures down somewhat with a relatively small amount of high 
clouds this weekend...but for the most part...mostly clear nights and 
sunny days are expected to continue through Thanksgiving. High 
pressure aloft between Hawaii and Baja California California is expected to 
build northeast over our area with temperatures rising to well above 
average for late November by Thanksgiving day. Highs in the desert 
areas including Phoenix...Yuma and el centro are expected to be in 
the upper 70s or lower 80s by Thanksgiving day. 


&& 


Discussion... 
under clear and sunny skies...temperatures were generally close to 
the same or a degree or so higher in southwest and south-central 
Arizona including the greater Phoenix area...and close to the same 
or a couple of degrees cooler in southeast California including the 
el centro/Imperial area early this afternoon compared with the same 
time yesterday. Wind was generally calm or light early this 
afternoon. 


Dry weather is expected to continue at least through Thanksgiving. 
The flow aloft will generally be from the northwest through Tuesday. 
In this flow...the dry and weak southern portions of Pacific low 
pressure systems are expected to bring temperatures down somewhat in 
southeast California and southwest Arizona including el centro... 
Imperial and Yuma Saturday...and south-central Arizona including the 
greater Phoenix area Sunday...close to or just slightly above 
average for the latter part of November. A relatively small amount 
of high clouds is also expected this weekend...but overall mostly 
clear nights and sunny days are expected to continue through 
Thanksgiving. 


High pressure aloft between Hawaii and Baja California California is expected to 
build northeast over our area with temperatures rising to well above 
average for late November by Thanksgiving day. Highs in the desert 
areas including Phoenix...Yuma and el centro are expected to be in 
the upper 70s or lower 80s by Thanksgiving day. 


Surface high pressure is expected to build north and east of our area 
and bring some breeziness at times from the north and east by 
Wednesday and Thanksgiving. 


&& 


Aviation... 
southeast California...southwest and south central Arizona...including kipl... 
kblh...kphx...and kiwa. 


Light winds...favoring typical diurnal patterns...will continue at 
least through Saturday. However...the wind will probably continue to 
be variable and very light at kphx through early this evening. Light 
wind is expected to become mostly from the west at kphx and kiwa and 
from the northwest or north at kipl and kblh Saturday afternoon. Some 
high cirriform clouds from the west will move across the area tonight 
and Saturday. 


Aviation discussion not updated for amended tafs. 


&& 


Fire weather... 
Sunday through Thursday... 
weak low pressure systems will move across the area this weekend... 
yielding slightly cooler temperatures and higher humidity values. 
High pressure builds over the western states early next week... 
bringing warmer temperatures...low daytime humidity values and 
modest overnight recovery through Thanksgiving day. Winds will favor 
north and northeast Tuesday through Thursday...gusty at times at the 
ridgetops. 


&& 


Psr watches/warnings/advisories... 


Arizona...none. 


California...none. 


&& 


$$ 


National Weather Service Phoenix is on the internet at 


Weather.Gov/Phoenix 


Discussion...Ellis 
aviation...Ellis 
fire weather...Meyers