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fxus65 ktwc 212001 
afdtwc 


Area forecast discussion 
National Weather Service Tucson Arizona 
115 PM MST Sat Nov 21 2009 


Synopsis...weather systems will continue to pass north of our area. 
Other than some occasional patches of high clouds...Southeast 
Arizona will remain dry with mostly clear skies and warm daytime 
temperatures. 


&& 


Discussion...trough digging into the intermountain west with energy 
and moisture tracking well north of our area. Modest gradient 
enhancement...probably won't see much difference compared to normal 
diurnal trends. Shortwave ridge with little inflection Sunday before 
another impulse rides through well north of the area Sunday night. 
Dirty ridge for much of the new week...but actual height and 
thickness gains will not be that unseasonable. Just a few degrees 
above climatology. Dry and relatively mild until further notice. 


&& 


Aviation...skc-few clouds mainly above 20k feet above ground level through 12z 
Sunday morning. Normal diurnal wind trends are expected at the 
terminal sites...with surface winds generally less than 10 kts. 
Aviation discussion not updated for taf amendments. 


&& 


Fire weather...a weather system will move across the Great Basin 
today with a stronger system expected to move through the northern 
rockies on Sunday. These systems will result in a little cooler 
daytime temperatures across Southeast Arizona...as dry conditions 
continue. There may be some afternoon and early evening breezes 
across the higher terrain to the north and east of Tucson today and 
Sunday...however...winds are expected to remain well below critical 
fire weather thresholds. 


&& 


Twc watches/warnings/advisories...none. 


$$ 


Weather.Gov/Tucson