Hail and Damaging Wind in Montana, June 12, 2026

Area Forecast Discussion
National Weather Service Great Falls MT
1259 PM MDT Fri Jun 12 2026

.KEY MESSAGES...

 - Showers and a few thunderstorms this afternoon and evening along
   and behind a cold front.

 - After a slightly cooler Saturday, temperatures trend warmer
   Sunday through Tuesday.

 - Breezy Tuesday and Wednesday.

&&

.DISCUSSION...

 - Meteorological Overview:

Upper level troughing dropping south from Canada is helping propel a
cold front southward across the region this afternoon. Showers and a
few thunderstorms will continue along and behind the front through
the afternoon and early evening. Small hail and gusty winds are the
primary concern, but a rogue stronger storm cannot be ruled out.
See more on this in the forecast confidence section. Most
precipitation ends this evening and tonight ahead of the coldest
air aloft. A few flakes of snow near the higher peaks is a
reasonable expectation at this point for the overnight.

Lingering cooler air aloft Saturday will combine with sufficient
daytime heating to result in additional showers and perhaps isolated
thunderstorms, mainly across Central and Southwest Montana from late
morning through early evening. Upper level ridging then begins to
build in, promoting largely clear skies and a warming trend. Before
the warming occurs there appears to be a risk for some frost Sunday
morning.

The building ridge looks to get flattened Tuesday into Wednesday,
which will promote breezy conditions, particularly over the plains.
The nature of the flow aloft looks to be a bit more cyclonic Tuesday
night into Wednesday, which would promote a return of precipitation
wherever the best forcing ends up developing.

Thereafter a northwesterly flow aloft slowly trends southwesterly,
which will gradually reintroduce afternoon/evening showers and
thunderstorms to the region toward next weekend. -AM

 - Forecast Confidence & Scenarios:

Stronger thunderstorms this afternoon:

Shear looks to gradually increase across Central Montana through the
afternoon. Instability increasing toward 500 J/Kg or so combined
with the locally higher effective shear will result in a narrow
corridor for a stronger thunderstorm or two across Central Montana,
capable of producing some larger hail (Perhaps up to an inch in
diameter) and gusty winds. Both shear and instability look to be
maximized across Central Montana this afternoon, with a less
favorable environment for stronger thunderstorms further north
across North-central Montana as well as further south across
Southwest Montana. -AM

Warm, windy, and, dry Tuesday...

Westerly winds begin to increase on Tuesday in advance of an
approaching through and cold front. The NAEFS anomaly index already
has H700/H500 winds approaching two to three standard deviations
above climatology with NBM probabilities for 50 mph + gusts already
running above 50% for portions of the forecast area, including the
Rocky Mountain Front/plains west of I15 and areas over and near the
higher terrain of central/southwest MT. The biggest uncertainty will
be when the strongest winds aloft move through and whether it will
be during peak diurnal mixing or later in the evening with less
momentum transfer.

With this event being four to five days out, there's plenty of time
to iron out any changes in trough/jet streak timing and positioning.
At this time, the primary impact looks be inclement outdoor
recreation and difficult travel for those operating high profile
vehicles. The combination of temperatures warming well into the 80s
and RHs falling to near critically low levels will also be monitored
for fire weather concerns, although fuels will be less receptive
given recent rainfall and greenup. - RCG

&&

.AVIATION...
12/18Z TAF Period

The cold front continue to push south across the state today,
which will result in scattered showers/isolated thunderstorms
along with a north/northwest wind shift at terminals. The main
hazards with thunderstorms will be gusty winds and small hail,
with best chances along and north of the MT Highway 200 corridor.
This front will also bring MVFR to IFR ceilings at times,
particularly with thunderstorms along the Hi-line this afternoon
and late tonight into Saturday morning across other terminals.
-Wilson

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  43  62  39  70 /  80  20   0   0
CTB  38  61  36  71 /  40  10   0   0
HLN  44  63  40  73 /  60  20   0   0
BZN  41  62  35  70 /  60  40  10   0
WYS  34  62  30  70 /  10  10  10   0
DLN  41  63  36  70 /  20  10   0   0
HVR  40  66  39  73 /  20  10   0   0
LWT  39  57  36  66 /  50  20   0   0

&&

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

http://www.weather.gov/greatfalls

Special Weather Statement
National Weather Service Great Falls MT
122 PM MDT Fri Jun 12 2026

MTZ303-304-309-122000-
Eastern Pondera and Eastern Teton MT-Eastern Toole and Liberty MT-
Eastern Glacier, Western Toole, and Central Pondera MT-
122 PM MDT Fri Jun 12 2026

...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN PONDERA...
SOUTHEASTERN GLACIER AND SOUTHWESTERN TOOLE COUNTIES THROUGH 200 PM
MDT...

At 121 PM MDT, Doppler radar was tracking a strong thunderstorm 11
miles southeast of Cut Bank, moving southeast at 25 mph.

HAZARD...Wind gusts up to 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

This storm will remain over mainly rural areas of northeastern
Pondera, southeastern Glacier and southwestern Toole Counties.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4850 11233 4858 11222 4841 11181 4825 11202
TIME...MOT...LOC 1921Z 308DEG 20KT 4849 11221

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Wilson

Special Weather Statement
National Weather Service Great Falls MT
144 PM MDT Fri Jun 12 2026

MTZ308-309-122030-
Eastern Pondera and Eastern Teton MT-Southern High Plains MT-
144 PM MDT Fri Jun 12 2026

...A STRONG THUNDERSTORM WILL IMPACT CENTRAL TETON COUNTY THROUGH 230
PM MDT...

At 144 PM MDT, Doppler radar was tracking a strong thunderstorm over
Choteau, moving east at 25 mph.

HAZARD...Wind gusts up to 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Choteau, Dutton, and Farmington.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4781 11232 4794 11228 4786 11168 4762 11179
TIME...MOT...LOC 1944Z 285DEG 21KT 4782 11220

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Wilson

Preliminary Local Storm Report
National Weather Service Great Falls MT
148 PM MDT Fri Jun 12 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0145 PM     Hail             1 NW Choteau            47.82N 112.19W
06/12/2026  M0.75 Inch       Teton              MT   CO-OP Observer

            Co op observer reports penny sized hail.

&&

AM

Special Weather Statement
National Weather Service Great Falls MT
209 PM MDT Fri Jun 12 2026

MTZ305-310-122100-
Hill County MT-Western and Central Chouteau County MT-
209 PM MDT Fri Jun 12 2026

...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN HILL AND NORTH
CENTRAL CHOUTEAU COUNTIES THROUGH 300 PM MDT...

At 209 PM MDT, Doppler radar was tracking a strong thunderstorm 21
miles west of Big Sandy, moving southeast at 20 mph.

HAZARD...Wind gusts up to 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Kenilworth.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4825 11067 4834 11050 4817 11012 4801 11034
TIME...MOT...LOC 2009Z 307DEG 19KT 4825 11057

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Wilson

Preliminary Local Storm Report
National Weather Service Great Falls MT
220 PM MDT Fri Jun 12 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0201 PM     Hail             20 S Rudyard            48.28N 110.60W
06/12/2026  E0.70 Inch       Chouteau           MT   Trained Spotter

            Trained spotter reports hail estimated to be
            dime sized. Time estimated from radar.

&&

AM

Special Weather Statement
National Weather Service Great Falls MT
225 PM MDT Fri Jun 12 2026

MTZ309-312-122115-
Eastern Pondera and Eastern Teton MT-Cascade County below 5000ft MT-
225 PM MDT Fri Jun 12 2026

...A STRONG THUNDERSTORM WILL IMPACT SOUTHEASTERN TETON AND
NORTHWESTERN CASCADE COUNTIES THROUGH 315 PM MDT...

At 225 PM MDT, Doppler radar was tracking a strong thunderstorm over
Fairfield, moving east at 20 mph.

HAZARD...Wind gusts up to 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor hail damage to vegetation is
         possible.

Locations impacted include...
Fairfield, Power, Vaughn, First Peoples Buffalo Jump State Park, and
Sun River.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4760 11205 4777 11201 4769 11147 4742 11153
TIME...MOT...LOC 2025Z 282DEG 19KT 4762 11194

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Wilson