National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KTFX 090335
AFDTFX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
835 PM MST Sun Dec 8 2013

.UPDATE...
Small changes to the precipitation probabilities before midnight
in the update. Main part of the snow has moved out of the area,
with some lingering over the Little Belts. Have generally trimmed
back the PoPs through midnight. No changes to the Winter Weather
Advisory, Wind Chill Advisory. nor the ice jam flooding near Gallatin
Gateway. db

&&

.AVIATION...
UPDATED 2350Z.
Weakening upper-level trof currently just south of KGTF will
continue to track to south-southeast this evening.  Periods of -SN
with MVFR and IFR conditions will continue along/south of a
KHLN-to-KLWT line thru 03-04Z when the trof exits into Wyoming.
Latest satellite imagery shows progressively clearing skies behind
the trof, and VFR conditions are expected at all airfields during
the overnight hours. Surface winds begin to steadily increase from
US/Can border down to KGTF/KLWT early Mon morning as pressure
gradient tightens ahead of next weather system dropping south from
Alberta. With gusts of 30-35 kts expected and plenty of fresh, dry
snow around, blowing snow limiting vis to 3-5 miles is likely at all
primary terminals except KBZN. Scattered areas of -SN will also
develop by late tomorrow morning vcnty KCTB/KHVR and spread south
during the afternoon.  Gusty winds continue thru the afternoon as
well, before gradually decreasing Mon evening.
Waranauskas

&&

.PREV DISCUSSION...
/ISSUED 450 PM MST Sun Dec 8 2013/
Tonight through Tuesday...Northwest flow aloft will continue over
the area with a series of embedded weather disturbances. One
weather disturbance will move out of the forecast area Sunday evening
and expect light snow to diminish the rest of Sunday afternoon and
evening. The strongest weather disturbance aloft will move into
the area Tuesday. Lift aloft from the disturbance along with low
level lift from a cold front will combine to produce snow over the
east slopes and the mountains. Expect accumulations of an inch or
two over the east slopes and up to six inches in the mountains. In
advance of Tuesday`s cold front expect gusty southwest winds and
temperatures will continue to moderate. The winter weather
advisory for central and north zones through Monday afternoon will
continue but have added a mention of light snow with the blowing
snow. Blank

Tuesday Night through Saturday...Medium range models continue to
agree that Montana will be underneath an unsettled northwest flow
aloft by midweek. The unsettled flow and occasional shortwave energy
remains favorable for slight chance to low chance pops across the
forecast area but there still does not appear to be any likelihood
for a large scale storm system. Also, shortwave ridging should move
over the region on Thursday for generally dry conditions with
temperatures near seasonable averages. However, unsettled flow
returns for Friday and Saturday before another weak transient ridge
improves conditions once again on Sunday. Overall, the entire medium
range period will see breezy westerly winds with temperatures that
are much milder than those seen over the last week. mpj

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  -6  19   7  20 /  20  30  20  70
CTB  -7  15   4  16 /  10  20  30  50
HLN  -6  18   9  23 /  20  30  20  50
BZN -13  13   4  21 /  30  50  30  60
WEY -22   6 -12  13 /  40  60  40  70
DLN -14  12   1  21 /  20  20  10  30
HVR -12  18   4  13 /  10  40  30  40
LWT  -7  22   8  20 /  30  50  30  70

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 5 PM MST Monday Central and
Southern Lewis and Clark.

WIND CHILL ADVISORY until 10 AM MST Monday Beaverhead...Blaine...
Broadwater...Cascade...Central and Southern Lewis and Clark...
Chouteau...Eastern Glacier...Eastern Pondera...Eastern Teton...
Fergus...Gallatin...Hill...Jefferson...Judith Basin...Liberty...
Madison...Meagher...Northern Rocky Mountain Front...Southern
Rocky Mountain Front...Toole.

WINTER WEATHER ADVISORY until 5 PM MST Monday Blaine...Cascade...
Chouteau...Eastern Glacier...Eastern Pondera...Eastern Teton...
Fergus...Hill...Judith Basin...Liberty...Northern Rocky Mountain
Front...Southern Rocky Mountain Front...Toole.

&&

$$


weather.gov/greatfalls
www.twitter.com/NWSGreatFalls
www.facebook.com/US.NationalWeatherService.GreatFalls.gov