Flash Flood in Colorado, August 6, 2002

Name: Flash Flood in Colorado, August 6, 2002
Start: 2002-08-06T13:15
End: 2002-08-06T15:00
Location: Colorado

August 6, 2002 · NWS GJT · 1 event in 1 county or zone

2 in several places, generally 6 to 8 feet deep. At one location, the water was 9 feet deep across the road.

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: $4,000
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 GJT wrote it up.

Flash flood waters traversed County Road 4.2 in several places, generally 6 to 8 feet deep. At one location, the water was 9 feet deep across the road. The road was washed out at a number of locations and stranded some ranchers.

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 Grand Junction, CO wrote its last area forecast discussion before the first event at Aug 6, 9:15 AM MST, 4 hours earlier.

Area forecast discussion, Aug 6, 9:15 AM MST, 4 hours before

WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
1015 AM MDT TUE AUG 6 2002

FLASH FLOOD WATCH HAS BEEN ISSUED FOR A GOOD PORTION OF OUR FORECAST
AREA.  AIR MASS REMAINS MOIST WITH PRECIPITABLE WATER EXCEEDING ONE
INCH (KGJT 12Z SOUNDING).. OR GREATER THAN 150% OF NORMAL.  SURFACE
DEW POINTS REMAINING IN THE 50S TO LOWER 60S.  A GOOD PORTION OF
SOUTHEAST UTAH AND SOUTHWEST COLORADO HAVE GENERALLY CLEARED OUT
BEHIND ONE MINOR WAVE EJECTING NORTHWARD.  GOOD SURFACE HEATING
THIS MORNING WILL ALLOW THE CONVECTIVE TEMPERATURE TO BE REACHED A
LITTLE EARLIER THAN YESTERDAY.  WINDS ALOFT A LITTLE SLOWER THAN
YESTERDAY.. WHICH MEANS STORM MOVEMENT WILL BE TAD SLOWER.  PF

.GJT...FLASH FLOOD WATCH UNTIL MIDNIGHT FOR SOUTHEAST UTAH AND
MOST OF WESTERN COLORADO.

The radar

The Grand Junction radar (KGJX), 22 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

1 flash flood. Local standard time, as filed.

Flash Flood, Mesa

When: August 6, 1:15 PM MST to 3:00 PM MST
Where: Mesa County, 4 mi NW of Gateway
Property damage: $4,000
Reported by: TRAINED SPOTTER
Coordinates: 39.018, -108.466 (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 Colorado in 2002 Every state in 2002 This day in weather history Warnings in Colorado, August 2002

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: 5317869.