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Area forecast discussion 
National Weather Service Great Falls Montana
250 PM MDT Fri Aug 1 2014

tonight through Sunday...short wave energy moves across the area
tonight. With an unstable airmass already in place, isolated
thunderstorms have begun to develop and will continue through the
evening. As has been the case the past few days, bulk shear is
very low and severe convective activity is not too likely. Models
continue to place a vort center moving across northern Montana
overnight and this may keep showers going. A stronger mid level
impulse will move across the area Saturday with thunderstorms
developing again during the afternoon and becoming a bit more
widespread in areal coverage. Precipitable water values also
increase a bit on Saturday. The pattern will continue through the
weekend with additional short wave energy kicking off isolated
thunderstorms again Sunday afternoon. Temperatures will continue
slightly above seasonal averages.

Sunday night through Friday...a repeat of the current pattern
continues through the long term. Warm temperatures and isolated to
scattered thunderstorms will develop each afternoon, generally
starting up over terrain. With the showery nature of monsoonal
moisture, uncertainty remains with precipitation amounts and
coverage. Areas near higher terrain have the best chance of seeing
precipitation, namely the Continental Divide and southwest Montana.
Latest forecast model runs suggest that increased coverage of
showers will develop Sunday afternoon/evening as a more defined
shortwave trough moves through the region. Drier conditions return
later next week as a high pressure rebuilds over the region.


updated 1800z.
VFR conditions are likely. Expect isolated thunderstorms this
afternoon and evening mainly over the mountains. The exception to
this will be the northern Rocky Mountain front and adjoining plains
which will include kctb where scattered thunderstorms are expected.
Thunderstorms will diminish after dark over most of the area.
However the approach of a weather disturbance aloft could result in
scattered showers and isolated thunderstorms over the northwest
portion of the area after dark. The taf site with the best chance of
seeing a shower or thunderstorm after midnight will be kctb. However
khln/kgtf/khvr could see a shower late tonight as well. For Saturday
morning although not mentioned in the tafs there will be a small
threat of showers or thunderstorms. Keep in mind gusty winds to 30
knots will be possible with thunderstorms. Blank


Preliminary point temps/pops...
gtf 59 88 60 89 / 20 30 20 20
ctb 54 83 57 84 / 40 30 30 20
hln 59 90 59 89 / 30 30 30 20
bzn 53 91 56 88 / 20 30 30 20
wey 44 79 48 80 / 30 20 20 30
dln 52 87 54 86 / 30 30 30 20
hvr 58 88 61 90 / 20 30 20 20
lwt 56 85 58 86 / 10 30 20 20


Tfx watches/warnings/advisories...



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