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Area forecast discussion 
National Weather Service Great Falls Montana
255 PM MDT Wednesday Jul 27 2016

Discussion...
tonight through Friday...an upper level disturbance will continue
to push southeast through the region this evening. Scattered
thunderstorms will be common for locations mainly north of A Butte
to Bozeman line. Some storms could be strong with gusty winds,
lightning, and brief heavy rain. An isolated severe storm is
possible, mainly in the Great Falls, Lewistown, and Helena areas
early this evening. For Thursday, drier air will slowly start to
move into the region, but just enough instability over the
mountains for a few thunderstorms to develop. The storms are not
expected to make it too far off the mountains at this time, so I
kept lower elevations mostly dry, but some adjustments are
possible later tonight. On Friday, isolated thunderstorm are
possible, mainly over north central Montana as the upper level ridge
builds to our west. Afternoon temperatures will be near normal for
both Thu and Fri. Brusda

Friday night through Wednesday...weak ridging aloft will yield dry
conditions across the forecast area Friday night. Saturday still
appears to be the warmest day of the period with southwesterly flow
aloft and westerly downslope winds at the surface. Models continue
to advertise scattered afternoon showers and thunderstorms over far
southwest Montana through the weekend associated with a northerly
push of monsoonal moisture. On Sunday afternoon a broad closed upper
low moving through western Canada will produce increasing winds as
its associated surface low deepens and moves through central and
eastern Montana. This could raise fire weather concerns over
southwest Mt where lower afternoon humidity is forecast. Temperatures
trend cooler to start next week as the Canadian low moves east of
the region. For now it appears the track of this system will keep its
associated precipitation north of our forecast area. However, a
secondary shortwave follows along the international border Tuesday
night producing chances for showers across much of north-central Montana.
Pn

&&

Aviation...
updated 1745z.
An upper level disturbance will move southeastward through the
region later this afternoon and during the evening hours. Expect
showers/thunderstorms to accompany this disturbance. Brief heavy
rain/gusty winds are the main threat. Most of the storms will
diminish after 08z. Otherwise VFR conditions should prevail. Brusda

&&

Preliminary point temps/pops...
gtf 56 85 56 89 / 20 10 10 10
ctb 55 81 55 85 / 30 10 10 10
hln 60 89 60 92 / 10 10 10 10
bzn 54 88 52 90 / 20 10 20 10
wey 46 79 43 80 / 20 10 10 10
dln 52 87 53 89 / 10 0 10 10
hvr 57 83 58 88 / 20 10 10 10
lwt 55 79 55 85 / 20 20 10 10

&&

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

$$

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