Heavy Rain, Yellowstone
- When
- June 22, 3:44 AM MST
- Where
- Yellowstone County, 1.18 mi SE of Pompeys Pillar
- Reported by
- Trained Spotter
- Coordinates
- 45.990, -107.930
One to 1.5 of rain reported in the Billings area.
75 within a few hours. At least minor flooding must have occurred, but no reports of impactful flash flooding.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS BYZ wrote it up.
Many thunderstorms produced heavy rainfall, with amounts anywhere from half an inch up to 1.75 within a few hours. At least minor flooding must have occurred, but no reports of impactful flash flooding. Gusts up to 71 mph were also observed.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Billings, MT wrote its last area forecast discussion before the first event at Jun 22, 12:13 AM MST, 3 hours 31 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Billings MT
113 AM MDT Mon Jun 22 2026
.KEY MESSAGES...
- Isolated to scattered showers and thunderstorms today. A few
thunderstorms may become strong to severe mainly east of
Billings. Main threats are hail, strong winds, and heavy rain.
- Mainly dry and trending warmer Tuesday and Wednesday.
- Daily chance of precipitation Thursday into the weekend.
- A strong weather system may (moderate chance) bring more
widespread precipitation and mountain snow to the area over the
weekend. Stay up to date with the latest forecast.
&&
.DISCUSSION...
Today through Sunday...
Scattered showers and isolated thunderstorms are forecast this
morning ahead of an approaching cold front. While instability
looks to be enough to support a heavier shower or thunderstorm at
times, the chance of seeing a severe thunderstorm early this
morning is very low. This changes late this morning into this
afternoon and evening when additional showers and thunderstorms
are forecast to develop as a cold front moves through the area.
With this, modest instability (CAPE values around 250 to 1250
J/kg), good shear (35 to 45 knots) due to an approaching jet
streak, and elevated precipitable water values (0.75 to 1.00 inch)
will support the potential for a few strong to severe
thunderstorms. At this time, the Storm Prediction Center has a
Marginal Risk (1/5) of severe thunderstorms over south- eastern
Montana and north- central Wyoming and a Slight Risk (2/5) of
severe thunderstorms over north-eastern Wyoming late this morning
into the evening. The main threats with any strong to severe
thunderstorm that develops are hail up to half dollar size (1.25
inches), strong wind gusts of 60+ mph, and heavy rain. The one
wrinkle in this severe thunderstorm potential is the morning
convection and associated cloud cover over eastern Montana, which
may stabilize the atmosphere and limit the strength and extent of
thunderstorms later in the day. On that note, this convection and
cloud cover may clear over south-central Montana earlier in the
day, so while this area is at a lower risk of severe weather, it
is an area to watch should better diurnal heating develop.
Currently, a few of the convective allowing models (CAMs) do show
a strong to severe thunderstorm developing that far west, so it is
something to watch.
Tuesday will be a drier day as cyclonic flow is replaced by an
approaching low amplitude ridge. With that said, there may be
enough elevated instability in the cyclonic flow to support a
light showers mainly near the mountains and foothills (10 to 25
percent chance). Wednesday will be another mostly dry day, though
a subtle wave ahead of the low amplitude ridge may bring light
showers to the area during the day (10 to 50 percent chance,
greatest over the mountains).
The weather pattern looks to become more active Thursday as a
more robust shortwave moves through the region. While some
uncertainty in the depth of this wave exists between models, there
looks to be enough instability and lift to favor afternoon and
evening showers and thunderstorms (moderate chance). Depending on
the depth of the wave, a few strong to severe thunderstorms could
also develop (low chance).
Friday into the weekend, a large weather system is expected to
move into the northwestern United States in some fashion. While
quite a bit of uncertainty remains in the track of this weather
system, ensemble forecasts suggest precipitation, cooler
temperatures, and windy conditions will impact portions of the
northwestern United States during this time. As for our area,
showers and thunderstorms on the leading edge of the weather
system are currently forecast on Friday. Depending on where the
core of the low pressure system goes Saturday into Sunday, our
area could see more widespread precipitation for the weekend, or
drier and more windy conditions. In addition, this weather system
may have enough cold air associated with it to support snow over
the higher elevations of the mountains (moderate chance). If you
have outdoor or travel plans late this week into the weekend,
especially in the mountains, make sure to stay up to date with the
latest forecast. LA
.AVIATION...
Scattered showers and isolated thunderstorms will move west to
east during the overnight hours. Brief MVFR conditions are
possible under thunderstorms. Far southeast MT has about a 20%
chance for fog/low stratus into the early morning hours,
preceding or mixed with light rain. MVFR ceilings will move into
northwest areas after 12z and may affect KBIL, lifting into the
afternoon. A few strong to severe thunderstorms are possible over
for areas generally east of KBIL this afternoon, lasting through
the early evening. The main threat with these storms will be large
hail, strong winds and heavy rain. MVFR to IFR conditions are
possible with the thunderstorms this afternoon and evening. STP
&&
.PRELIMINARY POINT TEMP/POPS...
Tdy Tue Wed Thu Fri Sat Sun
-------------------------------------------------------
BIL 072 051/075 053/076 053/081 055/089 060/077 051/069
4/T 30/U 12/T 13/T 21/B 48/T 75/T
LVM 073 044/075 046/075 046/079 048/085 049/069 041/062
3/T 20/U 01/B 24/T 22/T 49/T 87/T
HDN 073 048/075 049/076 050/081 053/089 058/078 049/071
5/T 40/U 12/T 15/T 31/B 37/T 86/T
MLS 071 049/072 048/073 050/078 054/083 058/079 053/070
5/T 50/U 01/B 03/T 41/B 45/T 65/T
4BQ 072 051/071 048/072 050/076 054/083 059/080 053/070
6/T 60/B 02/W 26/T 51/B 36/T 86/T
BHK 071 046/070 043/071 045/075 050/078 054/079 050/070
5/T 50/N 01/B 01/B 41/N 46/T 76/T
SHR 072 047/069 045/072 046/076 049/086 054/077 046/068
5/T 52/T 34/T 37/T 32/T 27/T 77/T
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
weather.gov/billingsPreliminary Local Storm Report
National Weather Service Billings MT
1146 PM MDT Sun Jun 21 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1115 PM Rain 1 NNE Sheridan 44.80N 106.95W
06/21/2026 M1.40 Inch Sheridan WY Trained Spotter
&&Special Weather Statement
National Weather Service Billings MT
200 AM MDT Mon Jun 22 2026
MTZ029-034-042-235-220845-
Musselshell MT-Southwestern Yellowstone MT-Golden Valley MT-
Northern Stillwater MT-
200 AM MDT Mon Jun 22 2026
...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL MUSSELSHELL...
SOUTHEASTERN GOLDEN VALLEY...WEST CENTRAL YELLOWSTONE AND
NORTHEASTERN STILLWATER COUNTIES UNTIL 245 AM MDT...
At 200 AM MDT, Doppler radar was tracking a strong thunderstorm 22
miles northwest of Billings, moving east at 25 mph.
HAZARD...Wind gusts up to 40 mph and pea size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Broadview, Comanche and Acton.
This does not include the city of Billings.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Monitor the weather situation closely and be alert for threatening
weather conditions.
Torrential rainfall is also occurring with this storm and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4591 10909 4619 10896 4616 10847 4583 10854
TIME...MOT...LOC 0800Z 279DEG 22KT 4603 10886
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH
PalmquistSpecial Weather Statement
National Weather Service Billings MT
244 AM MDT Mon Jun 22 2026
MTZ029-173-235-220930-
Southwestern Yellowstone MT-Northeastern Yellowstone MT-
Musselshell MT-
244 AM MDT Mon Jun 22 2026
...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL MUSSELSHELL AND
CENTRAL YELLOWSTONE COUNTIES UNTIL 330 AM MDT...
At 244 AM MDT, Doppler radar was tracking a strong thunderstorm 9
miles northwest of Shepherd, moving east at 15 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 damage to outdoor objects is
possible.
Locations impacted include...
Shepherd, Huntley, Worden and Ballantine.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Monitor the weather situation closely and be alert for threatening
weather conditions.
Torrential rainfall is also occurring with this storm and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4613 10867 4620 10871 4630 10821 4591 10806
4583 10849
TIME...MOT...LOC 0843Z 257DEG 12KT 4603 10849
MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH
PalmquistSpecial Weather Statement
National Weather Service Billings MT
329 AM MDT Mon Jun 22 2026
MTZ057-173-221015-
Northern Big Horn MT-Northeastern Yellowstone MT-
329 AM MDT Mon Jun 22 2026
...A STRONG THUNDERSTORM WILL IMPACT CENTRAL YELLOWSTONE AND NORTH
CENTRAL BIG HORN COUNTIES UNTIL 415 AM MDT...
At 329 AM MDT, Doppler radar was tracking a strong thunderstorm 7
miles northeast of Ballantine, or 27 miles northwest of Hardin,
moving east at 15 mph.
HAZARD...Wind gusts up to 40 mph and half inch size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is
possible.
Locations impacted include...
Pompeys Pillar.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Monitor the weather situation closely and be alert for threatening
weather conditions.
Torrential rainfall is also occurring with this storm and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.
&&
LAT...LON 4596 10814 4616 10834 4626 10794 4587 10756
4580 10798 4587 10805 4590 10805
TIME...MOT...LOC 0928Z 258DEG 14KT 4600 10801
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH
PalmquistThe Billings radar (KBLX), 54 km away, was scanning. The volume nearest the first event began at 10:42 UTC.
2 heavy rain, 1 thunderstorm wind. Local standard time, as filed.
One to 1.5 of rain reported in the Billings area.
Mesonet station GW4108 ROUNDUP reported 1.74 of rain.
Mesonet reported gusts up to 71 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2026Every state in 2026This day in weather historyWarnings in Montana, June 2026
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1358413, 1358414, 1358415.