Area Forecast Discussion
Issued by NWS Great Falls, MT
FXUS65 KTFX 241754
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
1055 AM MST Wed Dec 24 2014
Today...A cooler airmass will move into Central Montana today.
Snow is currently across portions of the northwest zones,
including Cut Bank and just reaching Great Falls. Snow will
continue to spread south during the day. Temperatures will be
falling behind the front through the day. The coldest air, which is
still north of the Canadian border, will not move south until this
evening. Strong winds across the Northern Rockies have reached
their peak and are diminishing. Will cancel the warning with this
Widespread snow across central Montana will continue through this
afternoon and overnight before gradually tapering off from the north
early Christmas morning. Rain and snow will spread into southwestern
Montana and change over to all snow by this evening and continue
through the end of the forecast period. LIFR/IFR conditions will
prevail in precipitation with VFR conditions rapidly deteriorating
as snow moves into an area. Mountains will be obscured through the
/ISSUED 445 AM MST Wed Dec 24 2014/
Wednesday through Friday Night...Precipitation moves into the
region from the northwest this morning, starting as light rain
in some locations before switching to all snow by Wednesday
evening. Southwest winds overnight have kept most temperatures
well above freezing so dropped the Winter Weather Advisory for
the Liberty, Hill, and Blaine region. Current model runs indicate
that the cold front will cross the Canadian border late morning,
with precipitation developing shortly after. Gusty winds and a
northerly wind shift will also accompany the frontal passage. Snow
will continue into Thursday, diminishing across North-Central
Montana mid Thursday and over Southwest MT by Thursday evening.
Travel will be difficult across the region. Total snow
accumulation of 2 to 5 inches is expected over the plains and
valleys, 4 to 8 inches over Central-Montana mountains, and 6 to 12
inches over the northern Rockies and Southwest Montana mountains.
The system exits the region Thursday night but another weak trough
looks to move into the region Friday. A chance of some additional
light snow is about all that will result. Overall temperatures
will trend downward through the next few days.
Friday night through Wednesday...Expect mostly quiet conditions to
generally start the period...as the region will be in between storm
system. There is a small chance for a passing snow shower Friday
night/Saturday...but the bulk of the light snow arrives Saturday
night into Sunday. Snow accumulations should be on the low side with
this event...with 1 to 3 inches at lower elevations and 3 to 6
inches in the mountains. Again the Havre region should be the area
that receives the least snowfall. Behind the cold front on
Sunday...much colder air will move into the region. Forecast models
for the last 2 nights have been consistent in bringing down the
arctic air. I have not gone as cold as this system could potentially
be...to keep consistent with adjacent NWS Offices...but I could
easily see temperatures for both highs/lows about 10 to 15 degrees
colder than currently forecast for Sunday night through Wednesday
morning. Thus later shifts will continue to monitor this closely for
possible adjustments. Most models start to move the cold air out on
Wednesday...I have followed suite...but this currently forecast
warm up beginning on Wednesday is a bit uncertain at this time.
Additionally only a scattered light snow shower is possible from
time to time Monday thru Wednesday...with little to no snow
accumulation expected. Brusda
.PRELIMINARY POINT TEMPS/POPS...
GTF 38 19 24 8 / 100 100 100 10
CTB 37 15 23 7 / 100 100 30 20
HLN 36 22 27 9 / 70 100 100 10
BZN 34 20 24 2 / 20 100 100 40
WEY 30 17 27 -2 / 60 100 100 40
DLN 35 21 27 7 / 30 100 100 30
HVR 37 20 26 13 / 90 100 30 20
LWT 43 20 23 7 / 60 100 80 20
WINTER WEATHER ADVISORY from 5 PM this afternoon to 5 PM MST
WINTER WEATHER ADVISORY until 5 PM MST Thursday Cascade...
Central and Southern Lewis and Clark...Chouteau...Eastern Teton.
HIGH WIND WARNING until 9 PM MST this evening For Route 287 over
Norris Hill in Madison County.
WINTER WEATHER ADVISORY until 11 AM MST Thursday Eastern
Glacier...Eastern Pondera...Northern Rocky Mountain Front...
Southern Rocky Mountain Front...Toole.