634
FXUS65 KTFX 162335
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
535 PM MDT Thu Oct 16 2025

Aviation Section Updated.

.KEY MESSAGES...

- Light rain and snow showers are ending over Southwest MT this
  afternoon, while some patchy fog continues to affect some
  mountain passes along the divide.

- It turns windy by Friday morning along the Rocky Mountain Front
  and in the Cut Bank area.

- A fast moving weather disturbance will move southeastward
  through the entire area Friday afternoon through Friday night,
  producing some light rain and snow.

- Afternoon temperatures will not be quite as warm this weekend as
  we were previously thinking earlier this week.

- Another weather disturbance, will move from west to east across
  the area Sunday afternoon through Monday morning, producing
  gusty winds over North Central MT, while accumulating snow falls
  in the mountains across the area.

&&

.DISCUSSION...
/Issued 319 PM MDT Thu Oct 16 2025/

 - Meteorological Overview:

Light precip continues to slowly diminish over Southwest MT this
afternoon. The precip is attached to a slow moving upper level
low currently over Wyoming, that is moving eastward. Overall most
of this precip should diminish by this evening. Some patchy
fog/low clouds continue to affect mountain passes along the
divide. With increasing winds overnight, the fog should move out
rather quickly.

On Friday, expect windy conditions to develop along the Rocky
Mountain Front and eastward out to the Cut Bank area. By Friday
evening, an upper level disturbance will move southeastward from
Canada, across the CWA. Light precip is expected with this
disturbance, with most of the precip ending by Saturday morning.
The precip is likely to start as rain at lower elevations, but
change to snow during the evening as colder air moves in.

Generally quite conditons are expected Saturday afternoon into
Sunday morning. With the next weather system arriving by Sunday
afternoon, it does not look like it will be as warm on Sunday as
it did earlier this week. Additionally, do expect another windy
day along the front range of the Rockies and across the western
portions of North Central MT. By Sunday night, another round of
rain/snow is expected to move west to east across the CWA.

For next week, a fairly brisk westerly flow aloft will set up over
the northern Rockies. This will allow a few weak weather
 to move eastward across MT during the week, just producing some
light precip. Generally seasonable temperatures are expected for
the first half of the week, with a trend towards above normal
temperatures by late next week.

 - Forecast Confidence & Scenarios:

Winds Friday -> Overall wind speeds should remain below warning
criteria for both the Rocky Mountain Front and the Cut Bank area.
There is less than a 10 percent chance of 60 mph winds in Cut
Bank on Friday.

Precip Friday afternoon into early Saturday -> Overall, there is a
70 percent chance for 1 inch of snow in the mountains over the
Rocky Mountain Front, Kings Hill and Big Sky area during this
period. At lower elevations, with a mix of rain/snow, any snow
accumulations will be minor and mostly on grassy areas or bridges.
There is some potential that a few heavier snow showers could
develop late in the afternoon because of some instability aloft,
but these areas should be fairly isolated. At this time, we are
thinking an SPS might be needed to highlight the areas of heavier
snowfall.

Precip/wind Sunday afternoon into Monday -> There is a 70 percent
chance wind speeds could reach 60 mph in the Cut Bank area on
Sunday. Thus there is the potential that high wind statements
might be needed for this event. Additionally, the average snowfall
is about 4 to 8 inches in the mountains across the CWA for this
event. Thus there is also the potential for some winter statements
with this event. Brusda

&&

.AVIATION...
17/00Z TAF Period

Clouds across Southwest MT and KLWT will clear out over the next
hour or two. VFR conditions then prevail through the TAF period.
Winds will start to increase overnight tonight and into Friday.
The strongest winds look to set up over KCTB, where west wind
gusts of up to 40kts are possible Friday morning. There will be
isolated instances of wind shear tonight and tomorrow morning.
-Wilson

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  39  59  29  56 /   0  10  60   0
CTB  38  54  27  52 /   0  40  20   0
HLN  35  59  32  55 /   0  10  60   0
BZN  29  59  28  53 /   0  10  40   0
WYS  24  44  21  45 /  20  10  40   0
DLN  29  59  27  54 /   0   0  10   0
HVR  34  59  27  54 /   0  30  20   0
LWT  32  58  27  52 /   0  10  60   0

&&

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

$$
http://www.weather.gov/greatfalls