A series of upper level shortwaves passed across Montana during the day on both September 2 and 3. This aided in thunderstorm formation in an environment marginally favorable for severe hail, and favorable for strong wind gusts (Deep inverted-V soundings).
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 TFX wrote it up.
A series of upper level shortwaves passed across Montana during the day on both September 2 and 3. This aided in thunderstorm formation in an environment marginally favorable for severe hail, and favorable for strong wind gusts (Deep inverted-V soundings). Only two severe caliber reports were received from these thunderstorms.
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 Great Falls, MT wrote its last area forecast discussion before the first event at Sep 2, 5:00 PM MST, 0 minutes earlier.
Area Forecast Discussion National Weather Service Great Falls MT 600 PM MDT Mon Sep 2 2024 Updated Aviation Discussion .SYNOPSIS... Hot and very dry conditions will continue through the rest of the day with wildfire smoke lingering over much of the region. Expect scattered showers and thunderstorms through the evening with a chance for gusty winds. Tomorrow there will be widespread showers and thunderstorms across the area with cooler temperatures. Isolated thunderstorms will produce severe wind gusts and/or severe hail tomorrow. On Wednesday it cools off some more with precipitation lingering before it drys out and warms back up for the weekend. && .DISCUSSION... Key Points for Today - Chance for showers and thunderstorms through the overnight hours for southwestern and central Montana - Main threat will be gusty and erratic winds as well as frequent cloud-to-ground lightning - Critical fire weather conditions for southwestern Montana will continue through 10 PM tonight - Smoky/hazy conditions will continue for much of the region through at least Tuesday Today...Showers and thunderstorms are already starting to form along the MT/ID border and will continue to develop and head to the northeast over the next few hours. The two main concerns this afternoon are dry thunderstorms with frequent cloud-to-ground lightning and gusty/erratic winds associated with any shower or thunderstorm that forms. These conditions, combined with expected highs in the upper 80s to low 90s and low relative humidity throughout the afternoon, continue to justify the Red Flag Warning currently out across southwestern Montana. Beyond southwest Montana, there is a concern that thunderstorms will become a wind threat for portions of central Montana as storms cross over the divide. In a scenario that has around a 20-30% of occurring based on the latest model guidance, wind gusts as high as 55 mph may be possible for some locations east of the divide as a potential line of storms moves to the northeast. -thor On Tuesday an upper-level trough associated with a surface cold front moves over North- central, Central, and Southwestern Montana. This will cool down temperatures to slightly above seasonal averages and bring showers and thunderstorms to the area. The SPC has a Marginal Risk (5% chance within 25 miles of a point) for severe winds across all of North-central, Central, and Southwestern Montana and for severe hail for areas along and south of the Montana Highway 200 Corridor. Isolated thunderstorms will produce strong to severe wind gusts on Tuesday across North-central, Central, and Southwestern Montana. Isolated thunderstorms along and South of the Montana Highway 200 Corridor will produce severe hail (1 inch or larger) on Tuesday. On Tuesday there is a 20 - 50% chance for a quarter inch of rain along and south of the Montana Highway 200 corridor. On Tuesday north of the Montana Highway 200 Corridor there is a 10 - 30% chance for a tenth of an inch of rain or greater. Wednesday through next Monday...On Wednesday the upper-level trough remains over North-central, Central, and Southwestern Montana. This will keep cold temperatures (about seasonal averages) and keep precipitation chances for the area. On Wednesday there a 10 - 20% chance for a tenth of an inch of rain or greater across North- central, Central, and Southwestern Montana. On Thursday an upper- level ridge begins to build back in over North-central, Central, and Southwestern Montana. This will keep the cooler temperatures across the area with dry weather. On Friday the upper-level ridge is over North-central, Central, and Southwestern Montana. This warms temperatures back up with dry weather for the area. On Saturday through next Monday clusters show an upper-level ridge remaining over North-central, Central, and Southwestern Montana. This will keep warm and dry weather over the area through the weekend. -IG && .AVIATION... 03/00Z TAF Period Initial round of showers/thunderstorms tracking NE across SW MT early this evening will dissipate but continue to bring some potential for a period of gusty winds as the remnants lift through central MT. Another round of showers and thunderstorms will track into western and SW MT later this evening and continue across central and SW MT overnight. Gusty winds and some brief mountain obscuration are possible at most central and SW MT terminals as this activity passes. Areas of smoke/haze will also continue to affect some terminals but will vary with the passage of any shower/thunderstorm activity. Hoenisch Refer to weather.gov/zlc for more detailed regional aviation weather and hazard information. && .FIRE WEATHER... A Red Flag Warning remains in effect for the Helena/Bozeman areas because of low humidity, gusty winds, dry conditions, and the potential for thunderstorms from 2 PM today until 10 PM tonight. An isolated thunderstorm will produce strong to severe wind gusts. All thunderstorms will produce gusty erratic winds, frequent lightning, and little if any rainfall. There is a 60% chance for wind gusts of 25 mph or more on Monday for the Red Flag Warning areas. On Tuesday temperatures cool down increasing the relative humidity and reducing the risk of rapid fire spread. -IG && .PRELIMINARY POINT TEMPS/POPS... GTF 60 86 53 80 / 10 40 40 10 CTB 57 82 51 73 / 10 20 20 10 HLN 58 84 53 83 / 30 70 50 10 BZN 52 85 47 79 / 40 60 50 20 WYS 44 73 36 72 / 40 50 30 10 DLN 49 77 45 75 / 60 60 30 10 HVR 58 89 55 78 / 10 10 10 20 LWT 57 84 51 79 / 10 40 40 30 && .TFX WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 10 PM MDT this evening for Helena and Townsend Ranger Districts of the Helena National Forest. && http://www.weather.gov/greatfalls
Special Weather Statement
National Weather Service Great Falls MT
327 PM MDT Mon Sep 2 2024
MTZ327>330-022200-
Ruby Mountains and Southern Beaverhead Mountains MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Northwest Beaverhead County MT-
Beaverhead and Western Madison below 6000ft MT-
327 PM MDT Mon Sep 2 2024
...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN MADISON AND CENTRAL
BEAVERHEAD COUNTIES THROUGH 400 PM MDT...
At 326 PM MDT, Doppler radar was tracking a strong thunderstorm 19
miles north of Lima, moving east at 20 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Dillon, Clark Canyon, and Beaverhead Rock State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4479 11274 4514 11294 4541 11217 4481 11211
TIME...MOT...LOC 2126Z 248DEG 17KT 4492 11268
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
WilsonSpecial Weather Statement
National Weather Service Great Falls MT
344 PM MDT Mon Sep 2 2024
MTZ328>330-022215-
Ruby Mountains and Southern Beaverhead Mountains MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Beaverhead and Western Madison below 6000ft MT-
344 PM MDT Mon Sep 2 2024
...A STRONG THUNDERSTORM WILL IMPACT SOUTH CENTRAL BEAVERHEAD COUNTY
THROUGH 415 PM MDT...
At 343 PM MDT, Doppler radar was tracking a strong thunderstorm near
Lima, moving east at 20 mph.
HAZARD...Wind gusts of 50 to 55 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Lima, Monida, Dell, Bannack Pass, and Snowline.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
If on or near Lima Reservoir, get out of the water and move indoors
or inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.
&&
LAT...LON 4440 11289 4445 11300 4452 11301 4460 11308
4462 11305 4469 11307 4489 11235 4454 11207
4452 11211 4457 11229 4453 11236 4445 11239
4450 11274 4444 11283 4438 11282 4436 11286
TIME...MOT...LOC 2143Z 248DEG 17KT 4468 11272
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH
WilsonSpecial Weather Statement
National Weather Service Great Falls MT
359 PM MDT Mon Sep 2 2024
MTZ325-328>330-022230-
Madison River Valley MT-
Ruby Mountains and Southern Beaverhead Mountains MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Beaverhead and Western Madison below 6000ft MT-
359 PM MDT Mon Sep 2 2024
...STRONG THUNDERSTORMS WILL IMPACT CENTRAL MADISON AND SOUTHEASTERN
BEAVERHEAD COUNTIES THROUGH 430 PM MDT...
At 358 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles southwest of Alder to 10 miles west of
Lima. Movement was northeast at 20 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Sheridan, Virginia City, Ennis, Lima, Alder, Monida, Jeffers, Laurin,
Snowline, and Monida Pass.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
If on or near Lima Reservoir, get out of the water and move indoors
or inside a vehicle. Remember, lightning can strike out to 10 miles
from the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not
be caught on the water in a thunderstorm.
&&
LAT...LON 4448 11247 4446 11251 4449 11260 4449 11279
4547 11225 4541 11158 4452 11210 4454 11221
4457 11223 4457 11229 4454 11232 4453 11236
4445 11239
TIME...MOT...LOC 2158Z 237DEG 16KT 4524 11217 4458 11279
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
WilsonSpecial Weather Statement
National Weather Service Great Falls MT
430 PM MDT Mon Sep 2 2024
MTZ324-325-328>330-022300-
Madison River Valley MT-
Ruby Mountains and Southern Beaverhead Mountains MT-
Missouri Headwaters MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Beaverhead and Western Madison below 6000ft MT-
430 PM MDT Mon Sep 2 2024
...STRONG THUNDERSTORMS WILL IMPACT CENTRAL MADISON AND CENTRAL
GALLATIN COUNTIES THROUGH 500 PM MDT...
At 430 PM MDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Virginia City to 24 miles south of Alder.
Movement was north at 25 mph.
HAZARD...Wind gusts up to 40 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Sheridan, Virginia City, Ennis, Alder, Mcallister, Jeffers, Laurin,
and Cameron.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4570 11220 4518 11240 4496 11192 4542 11124
TIME...MOT...LOC 2230Z 189DEG 20KT 4533 11192 4498 11221
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH
WilsonSpecial Weather Statement
National Weather Service Great Falls MT
459 PM MDT Mon Sep 2 2024
MTZ324>326-328-330-022330-
Madison River Valley MT-Missouri Headwaters MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Beaverhead and Western Madison below 6000ft MT-Gallatin Valley MT-
459 PM MDT Mon Sep 2 2024
...A STRONG THUNDERSTORM WILL IMPACT NORTHERN MADISON...SOUTHEASTERN
JEFFERSON AND CENTRAL GALLATIN COUNTIES THROUGH 530 PM MDT...
At 457 PM MDT, Doppler radar was tracking a strong thunderstorm 14
miles northeast of Ennis, moving northeast at 30 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Bozeman, Sheridan, Whitehall, Ennis, Twin Bridges, Pony, Harrison,
Norris, Big Sky, Mcallister, Bozeman Hot Springs, Gallatin Gateway,
Waterloo, Lewis And Clark Caverns State Park, Four Corners, and
Jeffers.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4553 11241 4575 11222 4575 11219 4576 11221
4588 11210 4567 11104 4520 11135
TIME...MOT...LOC 2257Z 214DEG 24KT 4547 11150
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
WilsonSpecial Weather Statement
National Weather Service Great Falls MT
529 PM MDT Mon Sep 2 2024
MTZ320-323>326-330-030000-
Madison River Valley MT-Missouri Headwaters MT-
Big Belt, Bridger and Castle Mountains MT-
Gallatin and Madison County Mountains and Centennial Mountains MT-
Canyon Ferry Area MT-Gallatin Valley MT-
529 PM MDT Mon Sep 2 2024
...A STRONG THUNDERSTORM WILL IMPACT SOUTHWESTERN BROADWATER...
NORTHEASTERN MADISON...SOUTHEASTERN JEFFERSON AND NORTHERN GALLATIN
COUNTIES THROUGH 600 PM MDT...
At 528 PM MDT, Doppler radar was tracking a strong thunderstorm 7
miles southwest of Belgrade, moving northeast at 25 mph.
HAZARD...Wind gusts up to 50 mph.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Bozeman, Belgrade, Three Forks, Manhattan, Harrison, Norris, Bozeman
Hot Springs, Gallatin Gateway, Missouri Headwaters State Park, Logan,
Amsterdam, Four Corners, Trident, Church Hill, Willow Creek, and
Madison Buffalo Jump State Park.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4534 11122 4553 11186 4607 11166 4586 11080
TIME...MOT...LOC 2328Z 211DEG 22KT 4570 11127
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH
WilsonThe Great Falls radar (KTFX), 187 km away, was scanning. The volume nearest the first event began at 00:01 UTC.
1 thunderstorm wind, 1 hail. Local standard time, as filed.
ASOS station KBZN Bozeman Yellowstone Airport measured a severe gust.
A Facebook report was received from local media reporting 1 inch hail. Time of event was estimated.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2024Every state in 2024This day in weather historyWarnings in Montana, September 2024
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: 1211440, 1211441.