Area Forecast Discussion
Issued by NWS Missoula, MT
FXUS65 KMSO 062033
Area Forecast Discussion
National Weather Service Missoula MT
233 PM MDT WED MAY 6 2015
.DISCUSSION...A surface low pressure system over central
Washington and Oregon will continue to influence the weather over
western Montana and central Idaho for the next couple days. At the
same time, a cooler air mass will begin to move south out of
Canada overnight. An influence of this pattern, will be a
tightening easterly gradient producing gusty east northeast winds.
The biggest impact will be on Flathead Lake. Winds will be
sustained 15-25 mph with gusts around 30-35 mph. This will create
choppy conditions late tonight into the morning hours on Thursday,
with a 2-4 foot chop expected. Due to this a lake wind advisory
has been issued for Flathead Lake from midnight tonight to noon
The low pressure system to the west will also help produce
scattered showers and thunderstorms across southwest Montana and
central Idaho each afternoon at least into Friday afternoon. High
temperatures will continue to run slightly below normal for the
region through Saturday afternoon.
Another potential impact of the cooler, moist pattern, will be the
possibility for some snow showers over the higher terrain of
southwest Montana and central Idaho. One particular location of
concern will be Lost Trail Pass for Thursday and Saturday
mornings. Roadways should be warm enough for what snow does fall
will melt. Some higher elevated valleys, such as Butte could even
see a few flakes mixing in with the rain.
Sunday will be fairly pleasant with the exception of a few
sprinkles possible over southwest Montana and Lemhi county.
Starting Monday a deep trough of low pressure will move over the
west coast. Models have been struggling on the placement of the
low, thus climo pops are reflected in the current forecast for the
long term. Overall, more showery weather should be expected by
around mid week.
.AVIATION...Low pressure to the west will continue to promote
mostly cloudy skies for aviation sites KMSO, KSMN, and KBTM. Also
scattered showers and thunderstorms will be possible for KSMN and
KBTM latter this afternoon until around 07/0300 this evening. A
strong easterly gradient will setup this evening, that will
produce gusty east northeast winds for KGPI and KMSO. Winds could
briefly gusts up to 25kts for a period of time before diminishing
after 07/0600 tonight.
MT...LAKE WIND ADVISORY from Midnight tonight to Noon MDT Thursday
for Flathead Lake in the Flathead/Mission Valleys.