Ledger, Montana Weather Forecast Discussion

519
FXUS65 KTFX 011123
AFDTFX
Area Forecast Discussion
National Weather Service Great Falls MT
523 AM MDT Wed Oct 1 2025
Aviation Section Updated.
.KEY MESSAGES...
- Breezy and dry today in most areas.
- Periods of precipitation Thursday and Friday, mainly along the
   Continental Divide and across Southwest Montana.
- A much cooler period this weekend, with an opportunity for
   mountain snow.
&&
.DISCUSSION...
- Meteorological Overview:
Southwesterly flow aloft will continue across the region ahead of a
nearly stationary upper trough near the Pacific NW coast. A lack of
any wave ejecting from this troughing today, along with weak surface
heating and mild air aloft should allow for a relative lull in
afternoon shower activity. That said, an isolated shower or two will
still be around today, mostly along the Continental Divide and
across portions of Southwest Montana near terrain. The main impact
to be felt today will be in the form of general breeziness from mid
morning through early evening.
Pacific NW troughing finally begins to budge Thursday, diving south-
southeastward toward CA and vicinity. Weak upper diffluence and jet
dynamics will help for a band of rain to form along with a few
showers Thursday into Thursday night, mostly across portions of
Southwest Montana.
As the upper trough begins to sneak eastward from CA toward NV, a
wave ejecting from the troughing along with additional jet support
will allow for additional periods of precipitation Friday into early
Saturday, primarily across Southwest Montana and vicinity. Any snow
that falls as a result of this precipitation across Southwest
Montana looks to be reserved to the highest peaks and struggle to
accumulate.
All the while, a compact wave diving southeastward out of BC looks
to reach the region during the day Saturday. This wave looks to send
a cold front from north to south through the region sending
temperatures to some of the coolest seen so far this fall Saturday
night into Sunday. There is still a large range of outcomes from
a precipitation perspective, but snow levels look low enough to
result in mountain snow in most ranges should precipitation be
favorably timed with this wave.
Precipitation looks to linger into Sunday, with overall cool/cold
conditions persisting. By Monday morning the chance for a
subfreezing low increases to greater than 70% at all lower elevation
locations, with many areas closer to 90%.
A building ridge off the BC coast and vicinity looks to result in a
northwesterly flow aloft heading toward Tuesday. After that model
guidance diverges significantly, largely related to high uncertainty
with respect to whether ridging continues or gets broken down
toward the middle and latter portion of next week. -AM
- Forecast Confidence & Scenarios:
There remains a large range of potential outcomes with respect to
precipitation this weekend. There is around a 20% chance for
little to no precipitation for many areas. Conversely, there is at
least a 30% chance for a quarter of an inch of precipitation in
most terrain over 48 hours ending Monday morning. This wide range
of outcomes leads to lower confidence for the snow forecast.
All that said, confidence is high that backcountry conditions will
be cold/raw regardless of significant precipitation. Those planning
to recreate in the mountains this weekend should remain aware of
trends in the forecast. -AM
&&
.AVIATION...
01/12Z TAF Period.
A few light rain showers will affect areas mostly along the divide
today. Otherwise, VFR conditions are expected to prevail across
the CWA. Do expect passing mid/high level clouds through the
afternoon, along with breezy surface winds this afternoon as well.
Brusda
&&
.PRELIMINARY POINT TEMPS/POPS...
GTF  71  44  72  48 /   0  10   0  40
CTB  64  39  66  41 /   0  10   0   0
HLN  72  45  70  46 /  10  10  20  50
BZN  71  43  70  43 /  10  10  30  60
WYS  59  32  64  34 /  20  10  30  40
DLN  67  41  64  42 /   0  10  30  60
HVR  74  44  74  45 /   0   0   0  10
LWT  72  43  72  44 /  10   0  10  50
&&
.TFX WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
http://www.weather.gov/greatfalls

NWS TFX Office Area Forecast Discussion