239 
fxus65 ktfx 052337 
afdtfx 


Area forecast discussion 
National Weather Service Great Falls Montana 
535pm MDT Sat Jul 5 2008 


Updated for aviation...corrected 


Discussion... 


Tonight through Monday...westerly flow aloft is expected for the 
remainder of the weekend into early next week. Weak instability 
each afternoon and evening will result in isolated showers and 
thunderstorms...mainly over the higher terrain of central and 
southwest Montana. The higher chance for precipitation will come on 
Sunday...as cooler air aloft moves southward across the 
region...aiding in additional instability. Otherwise...partly to 
mostly clear skies are expected through Monday...with temperatures 
near seasonal averages. Surface winds will be westerly through 
Monday...as a persistent surface high sets up over southwest 
Montana...with a surface trough over eastern Montana. Cohen 


Monday night through Thursday night...an upper level high 
pressure ridge will build over the Pacific northwest leaving the 
County Warning Area underneath light northwest flow aloft. High pressure slowly 
builds aloft until a low pressure moves over the West Coast 
Thursday morning. This slows the height rises across the zones 
but the airmass remains dry and precipitation free through 
Thursday night. Temperatures will trend slowly upwards through the 
period remaining well above normals. Zelzer 


Friday and Saturday...models in better agreement with an upper 
level low pressure trough moving in from the Pacific northwest. 
Increased chances for precipitation for much of the County Warning Area. 
Temperatures are expected to be slightly below seasonal averages. 
Saucier 


&& 


Aviation... 
updated 2330z. 
Westerly flow aloft with weak weather disturbance moving through 
south central Montana is generating some showers and isolated thunderstorms 
east of a kwys-to-klwt line. Precipitation will continue to move east 
tonight with sky clear-to-sct skies overnight. Second weak upper level 
system will move into the region on Sunday afternoon with wider coverage 
of showers and thunderstorms beginning 20z. VFR conditions will be 
the rule across the flying area but some sites may briefly see MVFR 
ceilings near any precipitation activity. Waranauskas 






&& 


Preliminary point temps/pops... 
gtf 54 82 52 80 / 20 20 20 10 
ctb 49 77 48 76 / 10 20 20 10 
hln 57 85 55 85 / 20 20 20 10 
bzn 53 86 50 85 / 20 30 20 10 
wey 43 72 42 77 / 30 30 30 10 
dln 47 81 47 82 / 20 20 20 10 
hvr 53 85 53 80 / 10 20 20 10 
lwt 51 80 50 77 / 20 20 20 10 


&& 


Tfx watches/warnings/advisories... 
none. 
&& 


$$ 


Short term...cohen 
long term...zelzer/Saucier 
aviation...loss 


Weather.Gov/greatfalls