Flash Flood and Hail in Montana, July 19, 2004

Name: Flash Flood and Hail in Montana, July 19, 2004
Start: 2004-07-19T03:00
End: 2004-07-19T14:50
Location: Montana

July 19, 2004 · NWS MSO · 4 events in 2 counties and zones

Early morning heavy rain soaked Kalispell with several business and basements reported flooded. An underpass in Kalispell was flooded with 4 feet of water.

Where it happened

Every event with a place to put it; 1 filed by county or forecast zone are drawn at its center, in a lighter ring. 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: $20,000
Crop damage: None recorded
Events: 4

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.

Early morning heavy rain soaked Kalispell with several business and basements reported flooded. An underpass in Kalispell was flooded with 4 feet of water. Later that afternoon a round of severe thunderstorms hit western montana producing hail and heavy rains. A roof was torn off a business in Plains with nickel sized hail reported to have damaged vehicles in Kalispell.

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 Jul 19, 1:40 AM MST, 1 hour 20 minutes earlier.

Area forecast discussion, Jul 19, 1:40 AM MST, 1 hour 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
240 AM MDT MON JUL 19 2004

.SHORT TERM...TODAY THROUGH TUESDAY...EXITING DISTURBANCE STILL
PRODUCING SCATTERED SHOWERS AND AN INFREQUENT LIGHTNING STRIKE OVER
NORTHWEST MONTANA THIS MORNING.  HAVE SOME SEEN SOME LOCALLY GOOD
MODERATE RAINFALLS IN THESE SLOW MOVING SHOWERS.

INTERESTING FORECAST AFTER DISTURBANCE EXITS THIS MORNING.  WILL
LIKELY SEE SOME BRIEF CLEARING AND SUBSIDENCE BEHIND THIS WAVE.
HOWEVER...AIR MASS QUITE UNSTABLE THIS AFTERNOON...AND WEST COAST
TROUGH ALREADY BEGINNING TO INTERACT WITH LAST REMNANTS OF
SUBTROPICAL MOISTURE OVER THE CASCADES. WHILE ATMOSPHERE IS NOT QUITE
AS MOIST AS YESTERDAY THERE IS STILL ENOUGH PRECIPITABLE WATER FOR
SIGNIFICANT LOCAL RAINS WITH DEVELOPING STORMS.  FLOW INCREASES FROM
THE SOUTHWEST OVERNIGHT WITH SHOWERS SLOW TO DISSIPATE. A COOL FRONT
WILL SLIDE THROUGH THE NORTHWEST MIDDAY TUESDAY WITH INCREASING WEST
FLOW.  SHOULD BE BREEZY BY AFTERNOON...ESPECIALLY THE HIGHER TERRAIN
AS WELL AS THE VALLEYS FROM MISSOULA NORTH.

TEMPERATURES AND HUMIDITIES WERE EXTREMELY VARIABLE YESTERDAY
DEPENDING ON CLOUD COVER.  VALLEYS IN THE NORTHWEST AND IDAHO CLIMBED
INTO THE 90S...WHILE WEST CENTRAL MONTANA STRUGGLED TO GET INTO THE
80S.  CHANGES TODAY WILL LIKEWISE BE INCONSISTENT WITH SLIGHT WARMING
IN SOME AREAS AND COOLING IN OTHERS.

TUESDAY NIGHT AND WEDNESDAY...DRIER AND MORE STABLE AIR SHOULD PUSH
ACROSS THE REGION.  THIS SHOULD BE SIGNIFICANT RELIEF TO THE WARM
OVERNIGHT TEMPERATURES WITH GOOD RADIATIONAL COOLING TUESDAY NIGHT
AFTER THE WINDS DIMINISH. THE AIR MASS IS ALSO SOMEWHAT COOLER
WEDNESDAY...BUT WITH LESS CLOUDS LITTLE OR NO TEMPERATURE CHANGE IS
EXPECTED.

.LONG TERM...THURSDAY THROUGH MONDAY...A WEAK UPPER LEVEL DISTURBANCE
MAY BRUSH THE AREA THURSDAY.  HOWEVER...WITH RELATIVELY LITTLE
MOISTURE TO WORK WITH AND HIGH PRESSURE GENERALLY IN CONTROL
...THE PRECIPITATION THREAT IS VERY SMALL. HIGH PRESSURE
SHOULD STRENGTHEN THROUGH THE REMAINDER OF THE PERIOD WITH WARM TO
HOT TEMPERATURES AND QUITE DRY CONDITIONS.
&&

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

SHORT TERM/WHITMORE
LONG TERM/BAUCK

Hazardous weather outlook, Jul 18, 7:24 PM MST, 7 hours 36 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE MISSOULA MT
815 PM MDT (715 PM PDT) SUN JUL 18 2004

IDZ005>010-MTZ001>007-043-190315-
NORTHERN CLEARWATER MOUNTAINS-SOUTHERN CLEARWATER MOUNTAINS-
OROFINO/GRANGEVILLE REGION-LOWER HELLS CANYON/SALMON RIVER-
WESTERN LEMHI COUNTY-EASTERN LEMHI COUNTY-KOOTENAI/CABINET REGION-
WEST GLACIER REGION-FLATHEAD/MISSION VALLEYS-LOWER CLARK FORK REGION-
MISSOULA/BITTERROOT VALLEYS-BITTERROOT/SAPPHIRE MOUNTAINS-
BUTTE/PINTLAR REGION-BLACKFOOT REGION-
815 PM MDT (715 PM PDT) SUN JUL 18 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL IDAHO AND WESTERN
MONTANA

.DAY ONE... TONIGHT

THE FLASH FLOOD WATCH HAS BEEN CANCELED FOR WEST CENTRAL MONTANA
AND NORTH CENTRAL IDAHO. NO HAZARDOUS WEATHER IS EXPECTED AT THIS
TIME.

.DAYS TWO THROUGH SEVEN... TUESDAY THROUGH SUNDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

The radar

The Missoula radar (KMSX), 140 km away, was scanning. The volume nearest the first event began at 20:15 UTC.

Open the radar archive at this moment

Event by event

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

Flash Flood, Flathead

When: July 19, 3:00 AM MST to 3:30 AM MST
Where: Flathead County, Kalispell
Property damage: $20,000
Reported by: LAW ENFORCEMENT
Coordinates: 48.295, -114.050 (the zone’s center; the record gives no point)

Thunderstorm Wind, Sanders

When: July 19, 1:17 PM MST
Where: Sanders County, Plains
Measured: 60 kt (69 mph) estimated sustained
Reported by: TRAINED SPOTTER
Coordinates: 47.450, -114.900

Hail, Flathead

When: July 19, 2:10 PM MST
Where: Flathead County, 6 mi N of Kalispell
Measured: 0.75 in hail
Reported by: TRAINED SPOTTER
Coordinates: 48.283, -114.317

Hail, Flathead

When: July 19, 2:50 PM MST
Where: Flathead County, Kalispell
Measured: 0.88 in hail
Reported by: TRAINED SPOTTER
Coordinates: 48.200, -114.317

What these are

Flash Flood: Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
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.
Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.

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

The same day elsewhere

Every storm in Montana in 2004 Every state in 2004 This day in weather history Warnings in Montana, July 2004

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: 5413383, 5413384, 5413385, 5413386.