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fxus63 kunr 231006 
afdunr 


Area forecast discussion for western South Dakota and northeastern Wyoming 
National Weather Service Rapid City South Dakota 
306 am MST sun Nov 23 2008 


Discussion...09z surface analysis shows trough located from 
northeastern North Dakota to southwestern South Dakota...moving 
east. Surface temperatures are warming behind the trough over 
northeastern Wyoming and western South Dakota. Area radars showing 
some weak returns...mainly virga...with only isolated light rain 
showers or sprinkles reaching the ground. 


The upper trough will cross the forecast area today...with colder 
temperatures increasing instability aloft...so expect to see a 
slight chance of rain or snow showers under mostly cloudy skies. 


Upper ridge builds across rockies for Monday...leading to dry 
northwest flow with a warming trend into the middle of the week. 


Extended...the upper level ridge will continue to bring warm temperatures 
and dry conditions on Wednesday...then an unsettled weather pattern 
develops for the beginning of the Holiday weekend. Models are having 
trouble coming to a common solution with the position of some key 
features...but with a generally unsettled pattern anticipated have 
gone with low end probability of precipitation for many areas Thursday into Friday. 


&& 


Aviation...a surface trough and upper level disturbance will move 
through the area today...with isolated rain or snow showers 
expected. Most locations should remain VFR...though ceilings may 
temporally lower to MVFR levels...particularly north and west of 
krap. Also...visible may temporarily lower to MVFR in the heavier snow 
showers. 


&& 


Unr watches/warnings/advisories... 
South Dakota...none. 
Wyoming...none. 


&& 


$$