North Browning, Montana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

875
FXUS65 KTFX 232005
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
205 PM MDT Tue Jun 23 2026

.KEY MESSAGES...

 - Showers and thunderstorms increase in coverage each afternoon
   through the remainder of the week.

 - Trending cooler with more widespread precipitation this weekend
   into early next week.

 - Impacts to recreation this weekend, including the risk for higher
   elevation snow.
&&

.DISCUSSION...

 - Meteorological Overview:

An active pattern looks to unfold over the next week or so across
the Northern Rockies. Departing upper level troughing is resulting
in a zonal to slightly northwest flow aloft ahead of weak shortwave
ridging. This ridging largely looks to suppress convection through
the remainder of the day, though some terrain based showers still
seems reasonable.

The first of several embedded waves within a building southwest flow
aloft Wednesday will result in increased shower and thunderstorm
coverage in the afternoon. Areas along and south of US-12 look to
have the greatest probability to see thunderstorms.

A stronger wave arrives heading into Thursday, which will result in
greater coverage of showers and thunderstorms across the entire
region. This wave does look to arrive slightly ahead of peak
afternoon heating, so there is some uncertainty in the magnitude of
instability that develops before convective initiation occurs.

Forcing becomes even stronger heading into Friday as a large upper
level disturbance moves southeast off the BC coastline toward WA and
vicinity. While the kinematic environment improves as this troughing
approaches, the thermodynamic environment looks to become a bit more
questionable - largely due to ample cloud cover associated with the
stronger forcing. While showers and thunderstorms are forecast
across the region Friday, confidence in a stronger thunderstorm
remains lower given this factor. Keeping along with the theme of
better kinematics, there does look to be some gusty synoptic winds
Friday, mainly south of I-90.

The core of the upper level disturbance moves across the Northern
Rockies this weekend. Temperatures trend cooler as a result,
presently looking coolest on Sunday. The main takeaway for the
weekend into early next week is cooler with precipitation around at
times. Confidence in specific precipitation amounts remains low
given the uncertainty with respect to the track of the upper level
low. Temperatures aloft look cool enough to support mountain snow
where the upper level low ends up moving over but again, confidence
in specifics remains low. -AM

 - Forecast Confidence & Scenarios:

Increased shower and thunderstorm activity Wednesday through
Friday...

Shortwave energy interacting with a seasonably unstable atmospheric
profile will result in increased shower and thunderstorm activity
during the second half of the workweek. Wednesday`s storms look to
be the most benign of the three days with showers and storms mostly
confined to and near the higher terrain of central and southwest MT.
Instability increases on Thursday for more widespread showers and
thunderstorms, but there are some disagreements on the strength and
evolution of the shortwave and the shear it will bring to the table.
Most members favor a weaker wave with less forcing and shear
availability for widespread strong to severe storms, though the
forcing looks sufficient for more widespread precipitation. On
paper, Friday looks to have the best overall kinematic
environment for stronger storms given increased shear/forcing
from the approaching Pacific NW trough; however, there`s nothing
really standing out as unusually strong or intense for this time
of year from an instability perspective. Impacts for all three
days will be mostly for those with outdoor recreation plans and
will include localized strong gusty winds, hail, downpours in
addition to lightning. -AM/RCG

Strong and gusty winds over southwest MT on Friday...

The combination of deep layer mixing and the strengthening
southwesterly flow may bring gusty to strong winds to southwest MT,
particularly over the higher terrain and the south to north oriented
valleys. Ensembles seem to be trending with the stronger winds aloft
developing to the east of the forecast area, though the set up still
favors breezy to windy conditions over the aforementioned areas. The
latest NBM probabilities for wind gusts over 50 mph, for most areas
south of the I-90 corridor, have fallen slightly to the 20 to 50%
range and the probability for 40 mph + sustained winds have largely
fallen below 15% at this time. This trend towards lighter winds is
fairly new and will be monitored in the coming days. It is also
important to note that any showers or thunderstorms that develop on
Friday will help transfer stronger wind gusts to the surface. Given
increased summer traffic across the area and more people recreating
in the mountains, stronger winds will be more impactful than the
winds normally observed during the cooler season.

Cool conditions with widespread precipitation and high mountain snow
this weekend...

Widespread rain showers and embedded thunderstorms are in the
forecast for the first half of the weekend with periods of moderate
to heavy stratiform rain and even high mountain snow Sunday into
Monday. The latest NBM probability for 1 inch of rain over the 72
hour period ending 6 am Tuesday is now running above 60% for
virtually the entire forecast area with roughly 15 to 30% chances
for 2 inches or more over most lower elevations during the same
period. Mountain snow will depend on where the cold core aloft sets
up and where any convective or heavier bands of precipitation
artificially lower snow levels with dynamic cooling. The cold core
looks to settle over the southwestern mountains Sunday into Monday,
but the higher terrain along the Continental Divide and even the
central ranges will need to be monitored for temporary lowering of
snow levels from dynamic cooling. Snow levels during this entire
event should range between 7000 to 9000 feet, lowest during the
overnight and early morning hours Saturday night through Monday
morning. Anyone with outdoor plans should plan for cool and damp
conditions that may be dangerous to those not properly dressed. Also
forest and rural roads may become muddy or even impassible from the
wet conditions. - RCG

&&

.AVIATION...
23/18Z TAF Period

Primary concern this TAF period will be for some early afternoon
cumulus briefly resulting in isolated MVFR ceilings. As daytime
mixing continues cloud bases slowly rise which will mitigate low
cloud concerns. Winds will remain on the lighter side through the
TAF period. -AM

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  48  75  49  76 /   0   0  10  60
CTB  46  73  47  75 /   0   0  10  60
HLN  50  78  52  77 /   0  10  30  80
BZN  46  79  47  76 /   0  10  20  70
WYS  39  77  39  72 /   0  40  40  70
DLN  46  79  46  77 /   0  20  40  60
HVR  44  75  48  78 /   0   0   0  40
LWT  42  69  45  70 /   0  20  10  80

&&

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

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