Scientific Forecaster Discussion
fxus65 kggw 090232
Area forecast discussion
National Weather Service Glasgow Montana
732 PM MST sun Dec 8 2019
went ahead and dropped the Winter Weather Advisory early since
accumulating snow has ended across the area.
Considered adding a Wind Chill Advisory for the northern tier of
zones (northern Phillips, northern valley, Daniels, and Sheridan
counties), but opted not to include in the update since these
areas should not reach the wind criteria (winds greater than 10
mph), with the possible exception of northern valley on the Opheim
plateau. Tomorrow night looks windier and colder, so a Wind Chill
Advisory will probably be needed for most of these areas tomorrow
night (excluding northern Phillips, where wind chills should stay
Otherwise, going forecast was on track.
winter storm has quickly impacted NE Montana today, and is already
beginning to weaken and dissipate from the west early this
afternoon. Based on radar and latest near term model trends, we
felt it was best to cancel the Winter Weather Advisory for
Phillips County with this forecast package issuance. The remainder
of NE Montana will also see the gradual end of snow. Next shift
will cancel as needed. About 5 inches of snow fell here at the
Tonight, only the far eastern edge of Montana may have a few
lingering snow showers. Otherwise, the cold Arctic airmass and
high pressure will have moved over the region and cutoff the
moisture supply from northwest to southeast. Also tonight and for the next 3
nights, wind chills will approach 20 below zero mainly across our
northern zones. If enough wind is involved, a Wind Chill Advisory
may be needed.
Monday, a subtle, short-wave disturbance will set off some low-
impact scattered snow showers.
Monday evening through Tuesday morning, models are hinting at a
banded light snow event along the sharp temperature gradient northwest to
southeast from Havre, through Zortman, through Jordan, through Miles
City. That should result in about another inch of snow for those
Wednesday, another short-wave disturbance will bring another
quick push of snow, this time to the NE corner of our County Warning Area.
Through the remainder of the week, expected generally moderating
conditions with less than average confidence.
Flight cat: improving to VFR, with periods of MVFR possible on
Discussion: ceilings will lift tonight, but could fall back to
MVFR levels on Monday afternoon as a chance of light snow returns
to the area. There could also be some blowing and drifting snow as
well by Monday afternoon, which could impact visibilities and
impact ground operations for snow removal.
Wind: light and variable tonight. Becoming northwest to north
10-20 kts with higher gusts by Monday afternoon, then light
(around 5 kts) Monday evening.