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fxus65 kfgz 301042 
afdfgz 


Area forecast discussion 
National Weather Service Flagstaff Arizona 
340 am MST Sat Aug 30 2008 


Synopsis....a trough of low pressure will move across the western 
United States this Labor Day weekend producing widespread rain 
and thunderstorms across the Northland. The period of heaviest 
precipitation is expected from late Saturday through Sunday 
afternoon. Drier and breezy conditions will develop by the middle of 
the week. 


&& 


Discussion...isolated thunderstorms are continuing across northern 
Arizona early this morning. Expect that activity will become more 
numerous through much of Labor Day weekend in advance of a deep 
500mb trough approaching from the West Coast of the United States. 
With deep moisture and decent shear dynamics...widespread rain and 
thunderstorms will be anticipated...especially from late Saturday 
night into Sunday afternoon. GFS and NAM model solutions want to 
place greatest quantitative precipitation forecast values across Coconino and Yavapai 
counties...though decent precipitation coverage should also take 
place over Apache...Navajo...and northern Gila counties as well. 
Continue to monitor upcoming forecasts for updates to the developing 
Labor Day weekend weather. From late Monday into the remainder of 
the week...the trough should push east and a drier and more stable 
air mass should settle across the Northland. Expect only slight 
chances for rain across the higher terrain and afternoon temperatures 
returning to near normal levels. 


&& 


Aviation...for the 12z package...expect isolated rain showers/thunderstorms and rain to diminish 
by 14z. However...sct-nmrs rain showers/thunderstorms and rain will redevelop around 18z with 
MVFR/IFR conditions likely in the the stronger storms. Expect 
rain showers/thunderstorms and rain to diminish to isolated-scattered after 02z. Aviation discussion not 
updated for amendments. 


&& 


Fire weather...see fire weather forecast (fwffgz) for discussion of 
days 1 and 2. 


Monday through Wednesday...an early season low pressure system will 
move across the southern Great Basin. Expect scattered showers and 
thunderstorms on Monday along with southwest winds of 10 to 20 miles per hour 
with gusts approaching 30 miles per hour during the afternoon and evening. On 
Tuesday and Wednesday...only isolated thunderstorm activity is 
anticipated at this time. 


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Fgz watches/warnings/advisories...none. 


&& 


$$ 


Public...............kd 
aviation/fire weather.....Jvc 


Visit weather.Gov/Flagstaff for northern Arizona weather 
information.