High Wind in Montana, June 6, 2026

Area Forecast Discussion
National Weather Service Great Falls MT
1114 AM MDT Sat Jun 6 2026

Aviation Section Updated.

.KEY MESSAGES...

- Scattered showers and isolated thunderstorms develop mainly along
  and east of I-15 this afternoon.

- Another round of scattered to widespread showers with isolated
  thunderstorms expected on Sunday.

- Breezy winds develop this weekend, especially in Southwest MT.

- An active, cooler weather pattern is on tap Tuesday through the
  work week.

&&

.UPDATE...
/Issued 805 AM MDT Sat Jun 6 2026/

Morning update has been published, with the only adjustment being
to increase PoP across northwestern portions of North Central
Montana; generally along and northwest of a Choteau to Havre line
to account for radar returns and latest Hi-Res guidance.

&&

.DISCUSSION...
/Issued 805 AM MDT Sat Jun 6 2026/

 - Meteorological Overview:

Southwest flow aloft today will continue to advect in moisture and
vorticity maximums across the region. This will bring in
scattered showers with isolated thunderstorms mostly along and
east of I-15 this afternoon. However, there will be some rain this
morning along the Rocky Mountain Front. With the stationary front
through Southwest/Central MT already, the thunderstorm threat
will most likely be off to the east. Mid level winds increases
throughout the afternoon, which will bring windy conditions to
Southwest MT.

On Sunday, the main trough axis moves through the region. A cold
front passage Sunday will bring better chances for scattered to
widespread precipitation during the day. Weak instability will allow
for some thunderstorms to develop, mainly towards Central MT. Snow
levels falling to 6,000 to 7,000ft Sunday morning along the
southern Continental Divide and down to 5,500ft towards the
northern Continental Divide will allow for light mountain snow to
develop. Below normal temperatures are expected Sunday. Stronger
flow aloft with the trough passing through will slow bring another
breezy to windy day, especially across Southwest MT.

With this trough exiting the region, Monday will be a drier day
overall. Though Southwesterly flow aloft will continue to bring a
low end chance for light showers during the day and breezy winds.
The main closed 500mb low moves onshore Tuesday, and slowly make
it's way east through eh week. This will bring another active,
cooler pattern for the week. There are some differences in models
with the amplitude and timing of this next trough, which will
bring subtle differences in precipitation amounts. However,
ensembles are in agreement for a wetter cooler pattern through at
least next Friday.

 - Forecast Confidence & Scenarios:

Weekend Thunderstorm Risk:

Generally, instability isn't really robust for thunderstorm
development today. Also, the main synoptic low being in the
eastern part of MT doesn't help place us in the best sector for
warm and unstable air. However, with winds aloft increasing in the
afternoon, I can't rule out a few strong winds with thunderstorms
in Southwest and Central MT.

The main limiting factor Sunday is the timing of the cold front.
The cold front is already reaching Fergus and Blaine County by
12pm, which does not support robust surface heating for
thunderstorms. A little slower in the time of precipitation will
increase the risk for stronger storms. With PWATs decreasing
throughout the day, the heavy rainfall threat with storms are low.

Lowering snowfall levels Sunday will allow for light snow to
develop, but light accumulations look to remain above pass level.

Winds This Weekend:

The pressure gradient front and increase in winds aloft will keep
windy conditions to Southwest MT Saturday and Sunday. The highest
impacts will be across the higher terrain, with only up to a 30%
for 50 mph wind gusts in the valleys near the MT/ID border.
However, showers could bring down some 50-55mph wind gusts to the
surface. Sunday's winds will be slightly higher, with up to a 50%
chance for 50 mph wind gusts in those valleys. -Wilson

&&

.AVIATION...
06/18Z TAF Period

Predominately low-VFR/VFR conditions are expected through the
0618/0718 TAF period, but low to mid-level cloud cover will be
increasing from southwest to northeast throughout the next 24
hours. Additionally, showers and thunderstorms will spread from
west to east across Southwest through North Central Montana
throughout this timeframe, with the greatest risk for
thunderstorms existing along and south of a KHLN, to KGTF, to KLWT
line. Primary concern with any thunderstorm will be gusty and
erratic winds, especially across the Southwest Montana terminals
(i.e. KBZN and KEKS). Mountains will become increasingly obscured
beyond 03-09z Sunday. - Moldan

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  72  44  57  39 /  40  70  70  40
CTB  65  40  56  37 /  60  20  40  20
HLN  74  44  58  37 /  50  50  80  10
BZN  80  43  60  32 /  30  40  60  30
WYS  77  40  58  27 /  20  30  30   0
DLN  78  42  59  33 /  30  40  40  20
HVR  76  44  60  40 /  40  70  60  30
LWT  77  42  56  35 /  40  70  80  30

&&

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

http://www.weather.gov/greatfalls