Arrastra Creek Trail, Montana Weather Forecast Discussion

449
FXUS65 KTFX 021026
AFDTFX
Area Forecast Discussion
National Weather Service Great Falls MT
426 AM MDT Thu Oct 2 2025
Aviation Section Updated.
.KEY MESSAGES...
- Today will be the last mild day for a while over the CWA.
- There will be a few passing showers today, but a better chance
  for showers and even a few stronger thunderstorms on Friday.
- Temperatures continue to cool over the weekend, with a chance
  for showers at lower elevations and snow in the mountains.
- A slow warming trend is expected by the middle of next week,
  along with mostly dry conditions from Mon thru Wed.
&&
.DISCUSSION...
- Meteorological Overview:
An upper level low is currently off the coastline of the Pacific
Northwest. This upper level low won`t move much today, but will
start to move eastward on Friday. Thus expect a few passing light
showers today, mostly over the Rocky Mountain Front and across
Southwest MT. On Friday, as the upper level low starts to move
eastward, there will be a better chance for showers and
thunderstorms, especially over Southwest MT. Additionally, a few
of the storms on Friday could be on the stronger side, mostly
south of a line from Helena to White Sulphur Springs.
On Saturday, and upper level disturbance will move southward along
the divide. Cooler air will accompany this disturbance. Rain and
snow will develop along the Rocky Mountain Front in the morning,
with the rain changing to snow during the day, as colder air moves
in from the north, also lowering the snow levels. Snow levels
start out around 7000 feet on Saturday morning, but lower to
around 4500 feet by Sunday morning. Light snow will impact Glacier
Park during the day on Saturday and into Saturday night. Over
Southwest MT, it will take a few more hours for the precipitation
to develop, but overall, Saturday afternoon and into Sunday
morning looks to be the wettest period for that portion of the
CWA. Precipitation amounts will also be higher over that portion
of the CWA as well. By midday Sunday, most of the precipitation
will be exiting the CWA.
Mild temperatures today will cool about 10 degrees each day over
the next few days. By Sunday, afternoon highs will only be in the
40s and 50s. Overnight lows go below freezing in many areas on
Sunday morning, but Monday morning could be even colder, with a
hard freeze likely for most areas.
For Monday through Thursday of next week...much of MT will be in
between storm system, thus it is looking mostly dry for much of
the first half of next week, along with a slow warming trend back
towards above normals temperatures by the middle portion of next
week.
- Forecast Confidence & Scenarios:
The main weather impacts over the next few days will be:
The thunderstorm potential on Friday over Southwest MT. Some
storms could produce stronger wind gusts, or even some hail,
because of the strength of the upper level system moving through.
For Saturday, accumulating snowfall of 1 to 4 inches could impact
the east side of Glacier Park and the Kings Hill area in Central
MT. There is a 45 percent chance that snow accumulations could
exceed 3 inches in these areas well. There is the potential that a
winter weather advisory might need to be issued for this event.
Further south, accumulating snowfall will also affect the
mountains of Southwest MT, with Madison and Gallatin counties
being most affected. There is a 60 percent chance that snow
accumulations could exceed 3 inches in the mountains of Madison
and Gallatin counties from Saturday night into Sunday, with snow
levels down to about 5500 feet over this portion of the state.
Winter weather statements are also possible for this portion of
the state this weekend as well. Brusda
&&
.AVIATION...
02/12Z TAF Period.
A few passing light rain showers will affect the CWA today. There
will be a better chance for a few heavier showers tonight, as an
upper level trof starts to approach the CWA from the west.
Otherwise, expect passing mid/high level clouds through the
period. Mountains/passes could be obscured at times by passing
showers. Brusda
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF  74  48  64  44 /  10  40  60  50
CTB  67  42  60  39 /   0  10  30  10
HLN  71  48  64  45 /  20  70  70  70
BZN  72  43  71  42 /  40  30  30  80
WYS  66  35  64  34 /  20  10  40  90
DLN  67  42  68  41 /  50  50  50  80
HVR  74  47  69  43 /   0  30  50  30
LWT  72  45  70  43 /  10  40  20  80
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
http://www.weather.gov/greatfalls

NWS TFX Office Area Forecast Discussion