Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Missoula Montana
413 am MDT Friday Aug 28 2015
..strong cold front Saturday, pattern change this weekend & next
Discussion...expect another day or two of smoky skies in the
northern rockies. Wildfires remain active, bringing very poor air
quality to many locations. Valleys of central Idaho will continue
seeing the worst of the smoke, but some locations in western Montana
remain unhealthy to very unhealthy.
A late-season monsoonal moisture push will brush the region of
southwestern Montana and Lemhi County of Idaho once again this
afternoon and evening. Storms will be isolated in nature, but
those that do get impacted, can expect gusty winds and occasional
Tomorrow will be the big story, as tomorrow will be the start of
our pattern change in the northern rockies. Precipitation will be
limited with the shortwave trough as it moves through the region,
with northwest Montana having the best chances of receiving any
measurable rainfall. The main story with this system, will be the
wind. Gusty southwest winds will first develop in the Camas
Prairie region of Idaho late Saturday morning and early afternoon.
Then will spread north through the rest of central Idaho and
western Montana soon after. The strongest winds will be ahead and
along the cold front as it makes its way through. Winds gusts of
40+ mph can is possible in the Camas Prairie in Idaho, and along
the Idaho/Montana border. Elsewhere 30-35 mph, with isolated areas seeing
stronger gusts will be common. Flathead Lake could be one of those
isolated areas that could see 40 mph or greater wind gusts, so if
you have plans on area lakes tomorrow, stay tuned to the forecast.
A distinct change in the pattern will be evident Sunday Onward,
with breezy and cool conditions across the northern rockies.
Northwest Montana will have the best chance of daily showers and
thunderstorms, particularly Sunday and the middle of next week.
The change in weather will also allow wildfire smoke to ventilate
and fire activity to slow a bit. That said, residual smoke is
unlikely to be completely eliminated by this pattern change
episode. There is some skepticism about the midweek wet weather
across the region, mainly because of recent bold stormy model
solutions that had quickly dried over time. On the other hand,
model confidence is high that cooler temperatures will materialize
and remain the norm beyond next week.
Aviation...smoke will continue to reduce visibility and obscure
terrain throughout the area, especially for the valleys of
central Idaho. Afternoon breezes could help thin the smoke out,
but only marginal visibility improvements can be expected.
Vicinity showers and thunderstorms will again be a threat for kbtm
and ksmn this afternoon and evening.
Montana...Fire Weather Watch from Saturday afternoon through Saturday
evening Bitterroot...deerlodge/west Beaverhead...east
Beaverhead...east Lolo...Flathead/Glacier park...salish and