Hail and Damaging Wind in Montana, August 10, 2005

Name: Hail and Damaging Wind in Montana, August 10, 2005
Start: 2005-08-10T14:57
End: 2005-08-10T19:45
Location: Montana

August 10, 2005 · NWS MSO · 3 events in 3 counties and zones

Strong summer storms brought hail and gusty winds to portions of Western Montana. Thunderstorm winds later in the evening caused two or more boats to be damaged on Flathead Lake.

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 3

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.

What happened

The episode as NWS MSO wrote it up.

Strong summer storms brought hail and gusty winds to portions of Western Montana. Thunderstorm winds later in the evening caused two or more boats to be damaged on Flathead Lake.

What forecasters said that day

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 Missoula, MT wrote its last area forecast discussion before the first event at Aug 10, 1:30 PM MST, 1 hour 27 minutes earlier.

Area forecast discussion, Aug 10, 1:30 PM MST, 1 hour 27 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
230 PM MDT WED AUG 10 2005

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...CONVECTION ACROSS
LEMHI COUNTY/SOUTHWEST MONTANA AND NORTHWEST MONTANA WILL CONTINUE
INTO THE EVENING. THESE STORMS WILL HAVE TO THE POTENTIAL FOR
BRIEF HEAVY RAIN AND SMALL HAIL. MUCH COOLER AIR POISED ALONG THE
FRONT RANGE OF THE DIVIDE NEAR GLACIER WILL TIGHTEN THE SURFACE
PRESSURE GRADIENT AND ONCE THE DAYTIME MIXING CEASES..NORTH TO
NORTHEAST WINDS SHOULD START PUSHING THROUGH THE GAPS OF THE
DIVIDE. THIS IS NOT EXPECTED TO BE A STRONG PUSH. A WEAK CANADIAN
SHORT-WAVE FEATURE WILL SAG SOUTH INTO NORTHERN MONTANA LATE
THURSDAY. THIS WILL TRANSLATE INTO A MUCH STRONG PUSH..DRAWING
COOLER MOIST AIR FAR SOUTH INTO NORTHWEST MONTANA. AT THE SAME
TIME...THE PLUME OF SUB-TROPICAL MOISTURE IN THE SOUTH WILL BE
REDIRECTED INTO SOUTHERN IDAHO. BREEZY NORTH TO EAST WINDS WILL
ACCOMPANY THIS COOLER AIR MASS THURSDAY NIGHT...IMPACTING MUCH OF
WESTERN MONTANA. THE SLIGHT CHANCE OF THUNDERSTORMS WILL CONTINUE
ACROSS NORTHWEST MONTANA...BUT IN A REDUCED MODE.

.LONG TERM...FRIDAY THROUGH WEDNESDAY...MAIN CHALLENGES FOR
LONG TERM FORECAST ARE THE LOW PRESSURE TROUGH CONTINUES TO MOVE
THROUGH THE PACIFIC NORTHWEST THROUGH SATURDAY NIGHT AND THE NEXT
SYSTEM EXPECTED WEDNESDAY. THE TROUGH COMING IN LATER THIS WEEK IS
NOW MUCH WEAKER THAN PREVIOUSLY PROGGED...SO HAVE DECREASED
CHANCES OF PRECIPITATION SOMEWHAT DURING THAT TIME FRAME.
CONFIDENCE IS FAIRLY LOW WITH THIS SYSTEM AS MODELS CONTINUE TO
WAIVER. INCREASED CHANCES OF PRECIPITATION TUESDAY AND WEDNESDAY
OF NEXT WEEK AS MODELS IN LINE WITH ANOTHER LOW PRESSURE TROUGH
MAKING ITS WAY INTO THE PACIFIC NORTHWEST. DUE TO MODEL
INCONSISTENCIES AT EARLIER TIME FRAMES...CONFIDENCE IS STILL LOW
WITH THIS SYSTEM. RIGHT NOW THOUGH IT LOOKS LIKE THE BEST CHANCE
FOR WIDESPREAD PRECIPITATION OVER IDAHO AND WESTERN MONTANA DURING
THE LONG TERM PERIOD.

&&

.AVIATION...NO SIGNIFICANT WEATHER IMPACT TO AVIATION EXPECTED...SEE
APPROPRIATE TAFS AND TWEBS.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
ID...NONE.
&&

SHORT TERM...MSJ
LONG TERM....STEGEMILLER
AVIATION...MSJ

The radar

The Missoula radar (KMSX), 137 km away, was scanning. The volume nearest the first event began at 21:55 UTC.

Open the radar archive at this moment

Event by event

2 hail, 1 thunderstorm wind. Local standard time, as filed.

Hail, Flathead

When: August 10, 2:57 PM MST
Where: Flathead County, 3 mi N of Kalispell
Measured: 0.75 in hail
Reported by: TRAINED SPOTTER
Coordinates: 48.250, -114.317

Hail, Silver Bow

When: August 10, 3:37 PM MST
Where: Silver Bow County, Melrose
Measured: 1 in hail
Reported by: GENERAL PUBLIC
Coordinates: 45.633, -112.700

Thunderstorm Wind, Lake

When: August 10, 7:45 PM MST
Where: Lake County, 6 mi NE of Polson
Measured: 50 kt (58 mph) estimated gust
Reported by: LAW ENFORCEMENT
Coordinates: 47.750, -114.083

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Montana in 2005 Every state in 2005 This day in weather history Warnings in Montana, August 2005

Sources

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: 5470402, 5470403, 5470404.