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fxus65 ktfx 220038 
afdtfx 


Area forecast discussion 
National Weather Service Great Falls Montana 
635 PM MDT sun Mar 21 2010 


..update to aviation... 


Discussion... 
tonight through Tuesday...expect a change in the weather pattern 
to begin tonight...as a Pacific storm system moves into the 
region. Scattered rain and snow showers should develop over 
southwest Montana this evening...and become more widespread by 
Monday morning. The precipitation will continue throughout the day 
on Monday over the southwest and the Rocky Mountain front. Snow 
accumulations look to be on the minor side at lower elevations 
because of the warm surface temperatures expect some melting of 
the snow...and for rain to be mixed with the snow at times. A bit 
more snowfall is possible in the mountains...mainly above 6000 
feet. Temperatures should be a few degrees below normal on Monday. 
The precipitation will continue into Monday evening...but should become 
more scattered and light. The chances for precipitation will decrease 
though-out the day on Tuesday...with only isolated mountain showers 
remaining on Tuesday afternoon. Temperatures should warm backup 
above seasonal normals by Tuesday afternoon. Brusda 


Tuesday night through Friday night...moisture associated with the 
Pacific system that impacted the region Tuesday will linger across 
central and southwest Montana until Tuesday night. Any precipitation 
received should be mountain snow and mixed precipitation over the 
plains and valleys. Tuesday night and Wednesday...a transient 
upper-level ridge will pass over the region with drier conditions 
and warmer temperatures around seasonal averages. Models differ 
slightly Thursday into Friday with scattered light precipitation 
moving into the region from the west. As a result...stayed close to 
climatology for temperatures and a little above climatology for 
precipitation during the second half of the extended forecast. 


Saturday and Sunday...latest models differ on timing of a quick 
moving Pacific disturbance expected to move into the region over 
the weekend. There will be a chance for snow showers along the 
Continental Divide and the central mountains. The plains can 
expect isolated rain and snow showers through the period. On the 
Central Plains temperatures are expected to be near average on 
Saturday and slightly above average on Sunday. 


&& 


Aviation... 
updated 0035z. 
The southwest flow aloft ahead of an approaching Pacific weather 
system will become increasingly moist over southwest...central... 
and north central Montana through 12z. Middle level clouds will 
increase over the terminals with precipitation obscuring mountain 
tops of western and southwest Montana. A band of showers with 
occasional MVFR conditions will also spread over khln...kbzn...and 
klwt during the period. A surface low pressure area will also move 
southeast through the area during the day on Monday as the Pacific 
system moves into the state. Mountains will become generally 
obscured in snow...while more widespread rain and snow showers will 
develop over the plains of north central and central Montana as 
surface winds there shift more northwesterly. These showers will 
again bring occasional MVFR conditions. Coulston 


&& 


Preliminary point temps/pops... 
gtf 36 47 29 49 / 20 70 40 10 
ctb 30 45 25 48 / 20 50 30 10 
hln 31 47 27 49 / 50 90 20 30 
bzn 31 45 23 45 / 30 90 50 30 
wey 23 37 12 38 / 40 90 70 40 
dln 29 44 23 44 / 50 90 20 20 
hvr 24 45 19 47 / 10 40 30 10 
lwt 34 46 27 45 / 20 40 40 20 


&& 


Tfx watches/warnings/advisories... 
none. 


&& 


$$ 


Weather.Gov/greatfalls