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Area forecast discussion 
National Weather Service Great Falls Montana
545 PM MDT Fri Sep 19 2014

Updated aviation section

Discussion...

Tonight through Sunday...a slightly unstable airmass coupled with
a weak disturbance moving southeast through Alberta has fueled a
few thunderstorms in far northeast Blaine County. This agrees well
with changes made with the morning update and this convection will
move into eastern Montana before 6 PM. An upper level ridge
develops along the West Coast tonight and will act to shunt the
Alberta disturbance away from my forecast area with skies expected
to clear out during the evening hours. The upper ridge will
continue to build through the weekend and is expected to nose into
the northern rockies by Sunday. The result of this activity will
be a mostly sunny and dry weekend with temperatures rising back
above seasonal averages by Sunday afternoon. Mpj

Sunday night through Friday...a high pressure ridge will be
moving east of the zones Sunday night and a weak shortwave will
track across southern Idaho towards central Montana. This will
bring moisture and instability across southwest Montana by Monday
afternoon and this flow continues through Tuesday. A slight
chance of showers or thunderstorms is expected but overall the
air mass will remain quite dry. A ridge will be in place again
over the region by Wednesday and the air mass will warm and temps
will be well above seasonal normals through Thursday. A deep low
pressure trof moving over the West Coast will bring moist,
unsettled flow aloft over central Montana by late Thursday
afternoon...and instability and a chance of thunderstorms will
again develop. Zelzer

&&

Aviation...
updated 2345z.
Generally dry northwest flow aloft will continue overnight. A few
isolated showers over northeast Montana will end by 04z. Gusty
surface winds along the Rocky Mountain front and adjacent plains
will decrease by 04z. VFR conditions prevail with possible MVFR
conditions in the vicinity of showers.

&&

Preliminary point temps/pops...
gtf 47 72 46 77 / 0 0 0 0
ctb 42 71 42 76 / 0 0 0 0
hln 47 76 46 79 / 0 0 0 0
bzn 43 74 41 75 / 0 0 0 0
wey 34 71 34 71 / 0 0 0 10
dln 45 75 45 76 / 0 0 0 0
hvr 48 72 43 78 / 0 0 0 0
lwt 48 70 45 74 / 0 0 0 0

&&

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

$$

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