Forecast Discussions mentioning any of
"ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 03/28/21
Area Forecast Discussion
National Weather Service Missoula MT
243 PM MDT Sat Mar 27 2021
...Damaging Winds Expected North-Central Idaho and Western
Montana Late Sunday Afternoon into Monday Morning...
.DISCUSSION...Big story this update is the very strong cold front
that is expected to plow through the region Sunday evening and
Sunday night. High temperatures Sunday will rise into the 50s and
60s for many locations with a fair amount of sunshine expected.
The trough associated with the cold front is very cold for this
time of year and temperatures will drop drastically by daybreak
Monday. Westerly winds will be ripping between 60 and 70 mph in
the mid-levels, some of which will plummet to the surface with
the strong cooling behind the front. Because of these conditions,
we have decent enough confidence that there will be wind damage
pretty much area- wide with the front and have issued high wind
warnings. Late Sunday afternoon, there is a decent possibility
that some of the increasing winds in the middle of the atmosphere
may be able to mix down to the surface..this will happen over
northwest Montana and also across southwest Montana. So make sure
you secure all loose items, small aircraft if outside of hangers,
and be prepared for possible power outages Sunday night.
Also with the front, we are expecting a brief period, possibly an
hour or two, of heavy snow with the front. This will mainly occur
at mountain passes and the higher elevation valleys like
Georgetown Lake, Anaconda, and Butte. With such a dramatic
temperature drop, temperatures will be in the 20s in many of these
locations, which will cause the moisture and snow to freeze,
causing slick conditions by daybreak Monday.
Snow showers will persist and it will feel much colder on Monday
with breezy northwest winds.
On Tuesday, temperatures remain below average and snow or graupel
showers will be possible. Light accumulations are expected.
Confidence continues to grow that a warming and drying trend will
occur with temperatures getting back to average or above by the
end of the week!
&&
.AVIATION...Southwest to westerly breezes up to 20 knots will be
possible for area terminals from 27/2100z to 28/0200Z. Confidence
continues to increase for a powerful Pacific cold front to impact
the Northern Rockies late Sunday afternoon into Monday morning.
Increasing winds are expected during the day Sunday, potentially
exceeding 45 knots at GPI and BTM after 28/2100Z, ahead of the
cold front. By Sunday night, snow levels will crash to valley
floors, a brief period of heavy snow will accompany the front,
along with wind gust potential near 50 knots.
&&
.MSO WATCHES/WARNINGS/ADVISORIES...
MT...High Wind Warning from 8 PM Sunday to 9 AM MDT Monday
Butte/Blackfoot Region.
Red Flag Warning from 1 PM to 7 PM MDT Sunday East Beaverhead.
High Wind Warning from 8 PM Sunday to 9 AM MDT Monday
Bitterroot/Sapphire Mountains.
High Wind Warning from 9 PM Sunday to 6 AM MDT Monday
Missoula/Bitterroot Valleys.
High Wind Warning from 3 PM Sunday to 6 AM MDT Monday Lower
Clark Fork Region.
High Wind Warning from 3 PM Sunday to 6 AM MDT Monday
Flathead/Mission Valleys.
High Wind Warning from 3 PM Sunday to 6 AM MDT Monday West
Glacier Region.
High Wind Warning from 3 PM Sunday to 6 AM MDT Monday
Kootenai/Cabinet Region.
High Wind Warning from 9 PM Sunday to 6 AM MDT Monday
Potomac/Seeley Lake Region.
ID...High Wind Warning from midnight Sunday night to 9 AM MDT Monday
Eastern Lemhi County.
High Wind Warning from 8 PM Sunday to 5 AM PDT Monday
Orofino/Grangeville Region.
High Wind Warning from 8 PM Sunday to 5 AM PDT Monday Southern
Clearwater Mountains.
High Wind Warning from midnight Sunday night to 9 AM MDT Monday
Western Lemhi County.
High Wind Warning from 8 PM Sunday to 5 AM PDT Monday Northern
Clearwater Mountains.
&&
$$