Area Forecast Discussion
Issued by NWS Glasgow, MT

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FXUS65 KGGW 060109

Area Forecast Discussion
National Weather Service GLASGOW MT
609 PM MST Mon Dec 5 2016

.SHORT TERM...for northeast Montana...tonight through Wed...
Wibeax county has been added to the Blizzard Warning as conditions
have deteriorated late this afternoon as heavier snowfall moved
into the area. A combined of the heavy snow, windy conditions, and
blowing snow producing near whiteout conditions across portions of
the county...especially in eastern sections.

Dry air is moving into eastern sections of northeast Montana this
evening and the dry air will help visibilities to slowly improve.
As the dry air progresses eastward this evening, blizzard
warnings may be cancelled between 7 to 10 pm.

The Snow Advisory for McCone county has been cancelled as the
drier air moved into the county.

Previous short term discussion: Very busy and complicated
forecast for tonight. Stronger than expected winds arrived this
morning and continue to spread through the region, causing the
lingering snow fall over our eastern zones to reduce area
visibilities significantly for some locations, and not so much for
other locations.

Much of the radar reflectivities are not showing the snow fall
evident in the observations basically near and east of the Big
Sheep Mountains.

Latest model precip consensus keeps lingering snow showers over
our eastern zones longer than previously shown. Based on reports
and observations, felt it was best to move forward with Blizzard
Warnings for our Sheridan, E Roosevelt, and Richland Counties.
Other surrounding locations in our CWA are showing slightly less
impacts and seem to be better served by a winter weather advisory.

Rather than confuse things with too many headline products, we
feel it is best to wait to issue the needed Wind Chill Advisory
until the current Winter Weather Advisory and Blizzard Warning is
finished this evening. later tonight, wind chill values near -20
below are expected near and north of Highway 2 and for the Little
Rocky Mountains. Over the next two nights, we are expecting wind
chill values of -20 to -30 across the entire CWA.


.LONG TERM...Wed night through Mon...

Very little was changed today as the focus was on Today`s storm.

Previous Discussion...
Pattern with longwave trof over North America is expected to
persist through next weekend. A slight shortwave ridge occurs over
the northern Rockies late in the week followed by more zonal flow
through the weekend.

Canadian high pressure pushes into the northern plains bringing
dry but still cold weather for Thursday. Temperatures will begin
to rebound by Friday as the upper flow turns more westerly. The
westerly flow will also bring increased pacific moisture spreading
across the divide which could bring snow to the region over the

Models current suggesting another surge of arctic air will drop
into the state early next week. Ebert



Snow and blowing snow will gradually improve from the west
through the evening.

Cold High Pressure will continue moving in tonight but low
ceilings will linger across the airports through Tuesday. TFJ

Blizzard Warning until 11 PM MST this evening for Eastern

Winter Weather Advisory until 11 PM MST this evening for Dawson.

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