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fxus65 ktwc 230855 
afdtwc 


Area forecast discussion 
National Weather Service Tucson Arizona 
155 am MST Monday Nov 23 2009 


Synopsis...weather systems will continue to pass north of our area 
and bring occasional patches of high clouds. Southeast Arizona will 
remain dry with warm daytime temperatures continuing. 


&& 


Discussion...water vapor imagery shows a trough moving through the 
north and central rockies with the only affect this far south being 
a band of clouds that extends generally east to west across northern 
New Mexico and Arizona. This system will continue to push into the 
Central Plains by late today. Dry northwesterly flow on the back 
side of this system will prevail across the southwest through middle 
week. A ridge will move in from the west...but will be centered over 
the Great Basin with a weak low under cutting the high. 


We should only warm a couple of degrees or so as the ridge axis 
moves overhead on Thursday. Thereafter...another Pacific system 
begins to make its way into the Pacific northwest by late Thursday 
or early Friday. This system will begin to impact the Desert 
Southwest late in the weekend and early next week. For now only 
expecting a decrease in high temperatures during this period and a slight 
chance of showers on Sunday for the White Mountains. Otherwise...a 
dry forecast will continue for the remainder of the forecast area. 
However...there still is some uncertainty as to the timing and 
intensity of this system...so the forecast may change during the 
next several days as models shed more light on this storm. 


&& 


Aviation...skc-few clouds mainly above 20k feet above ground level. 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 moving through the northern and 
central rockies will result in a little cooler temperatures across 
Southeast Arizona the next day or two...as dry conditions continue. 
There may be some afternoon and early evening breezes across the 
higher terrain to the north and east of Tucson...however...winds are 
expected to remain well below critical fire weather thresholds. 


&& 


Twc watches/warnings/advisories...none. 


$$ 


Mollere 


Weather.Gov/Tucson