Flash Flood in Montana, June 19, 2003

Name: Flash Flood in Montana, June 19, 2003
Start: 2003-06-19T16:00
End: 2003-06-19T18:00
Location: Montana

June 19, 2003 · NWS TFX · 1 event in 1 county or zone

A severe thunderstorm moved northeast across Central Cascade County during the evening hours of the 19th. One to two inches of rain fell in 30 minutes as the storm moved through.

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

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The toll

Deaths: 0
Injuries: 0
Property damage: $250,000
Crop damage: None recorded
Events: 1

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 TFX wrote it up.

A severe thunderstorm moved northeast across Central Cascade County during the evening hours of the 19th. One to two inches of rain fell in 30 minutes as the storm moved through. Flash flooding did occur in the towns of Sand Coulee and Tracy. Water flooded 25 homes and left roadways filled with mud and debris.

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 Great Falls, MT wrote its last area forecast discussion before the first event at Jun 19, 1:15 PM MST, 2 hours 45 minutes earlier.

Area forecast discussion, Jun 19, 1:15 PM MST, 2 hours 45 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
215 PM MDT THU JUN 19 2003

.DISCUSSION...

TONIGHT THROUGH SATURDAY...RATHER MOIST SW FLOW ALOFT WILL CONTINUE
OVER THE AREA INTO THE WEEKEND. LATE FRIDAY NIGHT AN UPPER TROUGH
MOVES INTO MT WEST OF THE CONTINENTAL DIVIDE THEN MOVES THROUGH THE
FORECAST AREA ON SAT. AT THE SURFACE A TROUGH FROM CENTRAL MT
THROUGH SW MT WILL NOT MAKE MUCH PROGRESS E OVERNIGHT BUT THEN WILL
ACCELERATE INTO THE ERN PLAINS OF MT FRI AFTERNOON AS DOWNSLOPE
INCREASES OVER THE E SLOPES OF THE ROCKY MOUNTAINS. ONE AREA OF
CONVECTION WILL SPREAD NE FROM SW MT TO N CENTRAL MT THU AFTERNOON
AND EVENING. A SHORTWAVE MAY SPAWN ANOTHER ROUND OF CONVECTION OVER
THE FAR WRN ZONES LATE TONIGHT WHICH WILL SPREAD E ON FRI. EXPECT
PRECIPITATION TO DIMINISH W TO E FRI AFTERNOON AND EVENING AS
SHORTWAVE MOVES E OF AREA AND DOWNSLOPE INCREASES. ON SAT THERE WILL
BE INSTABILITY AS THE UPPER TROUGH MOVES THROUGH THE AREA. BUT ON
THE OTHER HAND LOW LEVEL DOWNSLOPE WINDS WILL BE BLOWING OVER THE
PLAINS. ETA AND GFS DIFFER ON QPF FOR AREA ON SAT WITH GFS DRIER.
WILL CONTINUE WITH CHANCE POPS N BUT LOWER FAR S TO SLIGHT CHANCE AS
MOST MOISTURE AND DYNAMICS STAY N OF AREA. AS FOR SEVERE
WEATHER..SEVERE TSTM WATCH IS IN PLACE THROUGH THE EARLY EVENING
HOURS OF THU AND MAY NEED TO BE EXPANDED N AND/OR E DURING THE
EVENING. FRI AFTERNOON SURFACE TROUGH AND GREATEST INSTABILITY
ARE E OF FORECAST AREA BUT THERE STILL IS AN OUTSIDE CHANCE OF SEVERE
TSTMS OVER FERGUS AND BLAINE COUNTIES. BLANK

.SATURDAY NIGHT AND SUNDAY...UPPER TROF MOVES OVER THE AREA SATURDAY
NIGHT CONTINUING CONVECTIVE ACTIVITY. BY SUNDAY...FLOW ALOFT BECOMES
MORE WESTERLY ALLOWING FOR SOMEWHAT OF A RESPITE FROM SIGNIFICANT
WEATHER. ENOUGH INSTABILITY THOUGH FOR A SLIGHT CHANCE OF SHOWERS OR
THUNDERSTORMS.

.MONDAY THROUGH THURSDAY...CONVECTIVE PATTERN RETURNS MONDAY
THROUGH WEDNESDAY AS AN UPPER LOW MOVES ACROSS IDAHO AND NORTHERN
WYOMING. LOW LIFTS OUT THURSDAY LEAVING CWA UNDER NORTHWEST FLOW
ALOFT. CHANCE OF SHOWERS WILL CONTINUE EACH DAY.

.CCF NUMBERS
GTF TE 054/070 046/065 043 04664
    BBBBB 066/043 065/044 064/047 066/046 070 33233334433
CTB TE 055/064 044/062 041 04761
    BBEBB 063/045 061/044 063/045 065/045 068 33233333322
HLN TE 058/071 047/066 046 04665
    BBBBB 065/045 066/046 066/050 067/049 072 33233444433
BZN TB 051/072 044/065 040 04566
    BBBBB 065/040 064/043 066/046 067/045 069 33233444444
WEY TB 042/066 038/058 031 04467
    BBBBB 060/038 059/039 058/039 056/037 062 23233444455
DLN TB 054/067 044/064 038 04666
    BBBBB 064/040 064/042 066/047 065/042 071 23233444433
HVR TE 057/077 049/069 045 04664
    BBBBB 067/048 069/049 068/050 071/049 074 33233443333
LWT TB 054/075 046/065 042 04566
    BBBBB 062/044 061/045 063/047 065/045 068 33233444444

.TFX...SEVERE THUNDERSTORM WATCH THROUGH 7 PM SW MT AND PORTIONS OF
CENTRAL MT (ZONES 8/15/52 THROUGH 55/14/12/50).

Hazardous weather outlook, Jun 19, 12:40 PM MST, 3 hours 20 minutes before

MTZ008>015-044>055-200010-
HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE GREAT FALLS MT
140 PM MDT THU JUN 19 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTH CENTRAL AND SOUTHWEST
MONTANA

.DAY ONE...TODAY

A SEVERE THUNDERSTORM WATCH HAS BEEN ISSUED FOR SOUTHWEST MONTANA AND
PORTIONS OF CENTRAL MONTANA. SCATTERED THUNDERSTORMS ARE EXPECTED
ACROSS THE AREA THIS AFTERNOON THROUGH EARLY EVENING. SOME STORMS
MAY BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

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

In the hours before

Local storm report, Jun 19, 3:50 PM MST, 10 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREAT FALLS MT
450 PM MDT THU JUN 19 2003

TIME(MDT)  .....EVENT  LOCATION..... ST   ...EVENT/REMARKS...........
           .....COUNTY LOCATION.....

0420 PM    CHOTEAU                   MT   1 INCH HAIL
06/19/03   TETON

0440 PM    CHOTEAU                   MT   0.75 INCH HAIL
06/19/03   TETON

0445 PM    VALIER                    MT   1 INCH HAIL
06/19/03   PONDERA

NNNN

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

1 flash flood. Local standard time, as filed.

Flash Flood, Cascade

When: June 19, 4:00 PM MST to 6:00 PM MST
Where: Cascade County, Sandcoulee
Property damage: $250,000
Reported by: TRAINED SPOTTER
Coordinates: 47.308, -111.347 (the zone’s center; the record gives no point)

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.

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

The same day elsewhere

Every storm in Montana in 2003 Every state in 2003 This day in weather history Warnings in Montana, June 2003

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: 5366457.