Area Forecast Discussion
Issued by NWS Great Falls, MT

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FXUS65 KTFX 270205
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
805 PM MDT Tue Mar 26 2024

.SYNOPSIS...
Scattered light snow showers fall across The Continental Divide,
as well as, portions of central and southwest Montana, today. A
brief period of mild weather is forecast for tomorrow, before the
next period of cooler temperatures and unsettled weather moves
into the region.

&&

.UPDATE...
Updated forecast is out. Just minor changes to overnight lows for
current trends. Scattered snow showers continue to move southeast,
mostly across the Rocky Mountain Front and across Southwest MT.
They are diminishing as we lose daytime heating. Thus decreasing
Pops overnight look good. Patchy fog is possible, mostly for areas
east of a line from Cut Bank to Lewistown, as warmer air moves in
over the colder surface. Brusda

&&

.AVIATION...
640 PM MDT Tue Mar 26 2024 (27/00Z TAF Period)

A northwesterly flow aloft will keep scattered to broken mid-level
VFR cloudiness over North Central, Central, and Southwest Montana
through at least 09Z. Scattered snow showers due to weak lingering
instability may cause brief periods of MVFR/IFR conditions through
around 03Z south of a KGTF-KLWT line. Otherwise, skies should become
partly cloudy after 03Z as a high pressure ridge starts moving into
the area, which may allow patchy fog and low clouds with periods of
MVFR/IFR conditions to develop after 08Z and continue through around
17Z. Mid-level cloudiness may increase again after 20Z or so.
-Coulston

Refer to weather.gov/zlc for more detailed regional aviation
weather and hazard information.

&&

.PREV DISCUSSION...
/ISSUED 640 PM MDT Tue Mar 26 2024/

Today...Showery snow falls along The Rocky Mountain Front,
portions of central Montana, and the southwest region. Although
snow totals are expected to be minimal, due to convective nature
of this event, periods heavier snow and graupel may cause reduced
visibility, at times. Snow amounts of greater than one inch, are
generally restricted to the mountains. There is a 50% to 60%
chance of two or more inches of snow over Deep Creek Pass and
Kings Hill. The Storm Prediction Center (SPC) includes The
Continental Divide and southwest Montana in a region of general
thunderstorm activity; therefore, a few rumbles of thunder may be
heard and a few lightning strikes may be seen, this afternoon, in
these areas.
- Fogleman

Tomorrow...Upper level ridging then shifts east across the
Rockies, tonight and tomorrow, for a drier period with
temperatures warming back to seasonal levels. The shift to
westerly flow will bring some increased winds, initially along the
Rocky Mtn Front, but spreading to most of the area by tomorrow
afternoon. Strong winds are not anticipated but there is a 60% or
higher probability for gusts in excess of 40 mph along areas
adjacent to the Rocky Mtn Front as well as through the Madison
River Valley through Three Forks. Any drifting snow impacts should
be minimal and confined to the onset of winds early Wednesday.

Thursday through Early Next Week...The drier period is short-
lived with the next Pacific upper trough approaching the west
coast by Thursday. Southwest flow ahead of the trough will bring
an initial wave of moisture with an embedded Pacific cold front
moving across the region Thursday. This is a fairly quick moving
system with probabilities for precipitation amounts of 0.25” or
more ranging from 20% or less at lower elevations to around 60-70%
across some of the southwest MT mountain ranges. Snow
accumulations of 2 inches or more are similarly likely (>50%
chance) across the southwest MT mountains with the passage of this
system. Medium range model ensembles are in agreement to split
the offshore trough with a closed low tracking southeast toward CA
by the weekend. Further north there is some spread in the degree
of northern stream troughing to affect the northern Rockies and
MT. This would still provide a cooler and unsettled pattern for
the upcoming weekend with still some uncertainty regarding
precipitation. Hoenisch/Fogleman

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  23  47  30  46 /  10  10   0  70
CTB  20  44  25  44 /  20   0   0  30
HLN  27  51  33  50 /  20   0  10  80
BZN  20  49  29  50 /  20   0  10  80
WYS  14  37  25  40 /  20  20  80 100
DLN  23  46  32  47 /  20   0  20  80
HVR  12  44  23  43 /   0   0   0  40
LWT  20  46  29  50 /  10   0   0  70

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

http://www.weather.gov/greatfalls


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