323
FXUS65 KTFX 061906
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
106 PM MDT Sat Jun 6 2026

.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.

 - Strong and gusty winds across Southwest Montana today, with
   gusty conditions expanding to all areas on Sunday.

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

&&

.DISCUSSION...

 - Meteorological Overview:

Showers and thunderstorms will develop this afternoon across
Southwest and Central Montana before lifting northeast across the
remainder of Central and North Central Montana. Areal coverage of
precipitation will be highest from the late afternoon through
evening hours tonight, especially along northeast of a Ennis, to
Helena, to Great Falls, to Havre line. A few of the thunderstorms
over this timeframe could produce strong and gusty winds, especially
across Southwest Montana and portions of Central Montana (Judith
Basin, Fergus, and Blaine Counties). - Moldan

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. - Wilson

 - Forecast Confidence & Scenarios:

Strong and Gusty Winds through Sunday

Strong and gusty winds initially over Southwest Montana today,
mainly south of the I-90 corridor, will expand across the remainder
of Southwest through North Central Montana for the day on Sunday.
For areas along and southeast of a Dillon, to Ennis, to Big Sky
there is a 50% or greater chance for wind gusts to exceed 40 mph
through the remainder of the afternoon and into the evening hours,
with even a 30-70% chance that gusts exceed 50 mph. Isolated higher
wind gusts are possible through the afternoon and evening hours
today beneath decay showers and thunderstorms given inverted-V
soundings across the area. By Sunday increasing cross barrier flow
associated with the upper level low moving overhead will help to
support strong and gusty west winds across all areas, with a 40% or
greater chance for wind gusts of 40 mph across any given area and a
60-80% chance for gusts of 50 mph along the Rocky Mountain Front and
southeast of a Monida Pass to Big Sky line. - Moldan

Thunderstorm Risk through Sunday:

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. - 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  44  57  39  70 /  70  70  40   0
CTB  40  56  37  66 /  20  40  20   0
HLN  44  58  37  70 /  50  80  10   0
BZN  43  60  32  70 /  40  60  30   0
WYS  40  58  27  64 /  30  30   0   0
DLN  42  59  33  68 /  40  40  20   0
HVR  44  60  40  72 /  70  60  30   0
LWT  42  56  35  70 /  70  80  30   0

&&

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

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