Flash Flood, Grand
- When
- August 1, 3:10 PM MST to 4:30 PM MST
- Where
- Grand County, Castle Valley
- Reported by
- TRAINED SPOTTER
- Coordinates
- 38.667, -109.417
Flash Flood in Utah, August 1, 2005
Water 6 to 8 feet deep and 30 to 40 feet wide rushed down Castle Creek carrying lots of rocks. Water 3 to 4 feet deep was also rushing down Professor Creek.
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
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- None recorded
- 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.
Water 6 to 8 feet deep and 30 to 40 feet wide rushed down Castle Creek carrying lots of rocks. Water 3 to 4 feet deep was also rushing down Professor Creek. The torrent lasted about 20 minutes.
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 1, 1:20 PM MST, 1 hour 50 minutes earlier.
Area forecast discussion, Aug 1, 1:20 PM MST, 1 hour 50 minutes before
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 220 PM MDT MON AUG 1 2005 .SHORT TERM (TONIGHT THROUGH WEDNESDAY)... HIGH PRESSURE REMAINED OVER THE SOUTHEAST PLAINS OF COLORADO EARLY THIS AFTERNOON. THUS...SUB-TROPICAL MOISTURE PLUME CONTINUED TO SURGE NORTHWARD ACROSS UTAH...THEN EAST ACROSS NORTHERN COLORADO. MOISTURE HAS CONTINUED TO SPREAD EAST AS EVIDENCED BY INCREASING DEW POINT VALUES ACROSS THE CWFA. IN ADDITION...PW VALUES OVER ONE INCH WERE PRESENT IN THE 12Z KGJT SOUNDING. MEANWHILE...CLOUD SHIELD OVER AREAS OF DEEPEST MOISTURE HAS KEPT CONVECTION BACK WHEN COMPARED TO YESTERDAY AT THIS TIME. .TONIGHT: SHORTWAVE MOVING NORTHWARD INTO SOUTHERN UT EARLY THIS AFTERNOON APPEARED WELL HANDLED BY THE NAM AND GFS. APPEARS THIS FEATURE WILL BE MORE OF A PLAYER LATER TONIGHT THAN THIS EVENING AS IT BEGINS TO SHIFT EAST LATE. CONSEQUENTLY...UPPED POPS ACROSS EASTERN UTAH AND WESTERN COLORADO LATE TONIGHT AND EARLY TUESDAY. OVERNIGHT LOWS WILL REMAIN MILD DUE TO CLOUD COVER AND INCREASED LOWS FROM PREVIOUS FORECAST BASED ON HIGHER THAN EXPECTED LOWS RECORDED THIS MORNING. .TUESDAY: SHORTWAVE CONTINUES TO TRACK EASTWARD ACROSS THE CWFA AS UPPER LEVEL TROF MOVES ACROSS THE NORTHERN TIER OF THE U.S. FLATTENING THE HIGH PRESSURE RIDGE OVER THE AREA. EXPECT THIS FEATURE WILL ENHANCE STORM DEVELOPMENT AND AREAL COVERAGE ON WEDNESDAY... THOUGH MAINLY NORTH AS SOUTHERN ZONES SHOULD REMAIN A BIT DRIER BY COMPARISON. AFTERNOON HIGHS WILL CONTINUE A DOWNWARD TREND AS IN PREVIOUS FORECAST. .TUESDAY NIGHT-WEDNESDAY: MORE OF THE SAME ON TAP AS SUB-TROPICAL MOISTURE LINGERS OVER THE CWFA. THEREFORE...CONTINUED HIGH CHANCE AND LIKELY POPS OVER THE MOUNTAINS DURING THE DAY WITH LOW END CHANCE POPS IN THE VALLEYS AND DIURNAL DECREASE IN SHOWER/TSTM ACTIVITY DURING THE NIGHT. AFTN HIGHS SHOULD CONTINUE TO TREND DOWN WHILE EXPECT LOWS TO BE FAIRLY PERSISTENT AND A LITTLE ABOVE NORMAL DUE TO CLOUD COVER. .LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...LATEST MONSOONAL BURST WILL CONTINUE INTO THE BEGINNING OF THE WEEKEND...WITH SOME DRYING AFTERWARDS. SUBTROPICAL PLUME FROM WESTERN MEXICO WILL CONTINUE TO BE ADVECTED IN THROUGH THE FIRST PART OF THE PERIOD. DEEP MOISTURE IS FORECAST THROUGH AT LEAST LATE FRIDAY, ACCOMPANIED BY WEAK SHEAR ALOFT. THE GFS PLACES THE CENTER OF HIGH PRESSURE OVER KANSAS BY THURSDAY... WITH SOME RIDGING EXTENDING WESTWARD INTO THE GREAT BASIN. BY FRIDAY 00Z...A WAVE EMBEDDED IN THE WESTERLY FLOW NORTH OF THE RIDGE LOOKS TO PUT A DENT IN THE NORTHERN PART OF THE RIDGE, PROVIDING SOME DECENT DYNAMICS FOR THE CWA (ESPECIALLY NORTH) ON FRIDAY AND FRIDAY NIGHT. DRYING AND SOME COOLER AIR BEHIND THIS SYSTEM WILL RESULT IN A SLIGHTLY COOLER SATURDAY MORNING. HOWEVER, TEMPERATURES SHOULD REBOUND QUICKLY AFTER THAT AS THE RIDGE BUILDS BACK UP. ENOUGH RESIDUAL MOISTURE FOR HIGHER TERRAIN CONVECTION...BUT CHANCES DIMINISH FOR THE LOWER VALLEYS FOR THE REMAINDER OF THE WEEKEND. && .GJT WATCHES/WARNINGS/ADVISORIES... .CO...NONE. .UT...NONE. && NL/BA
Hazardous weather outlook, Aug 1, 7:37 AM MST, 7 hours 33 minutes before
HAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE GRAND JUNCTION CO 837 AM MDT MON AUG 1 2005 CORRECTED TO INCLUDE ALL OF W CO AND E UT COZ001>014-017>023-UTZ022>025-027>029-021300- ANIMAS RIVER BASIN-ARCHES/GRAND FLAT-CANYONLANDS/NATURAL BRIDGES- CENTRAL COLORADO RIVER BASIN- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- CENTRAL YAMPA RIVER BASIN-DEBEQUE TO SILT CORRIDOR- EASTERN UINTA BASIN-EASTERN UINTA MOUNTAINS- ELKHEAD AND PARK MOUNTAINS-FLAT TOPS- FOUR CORNERS/UPPER DOLORES RIVER- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAINS-GRAND AND BATTLEMENT MESAS- GRAND VALLEY-LA SAL AND ABAJO MOUNTAINS-LOWER YAMPA RIVER BASIN- NORTHWEST SAN JUAN MOUNTAINS-PARADOX VALLEY/LOWER DOLORES RIVER- ROAN AND TAVAPUTS PLATEAUS-SAN JUAN RIVER BASIN-SOUTHEAST UTAH- SOUTHWEST SAN JUAN MOUNTAINS-TAVAPUTS PLATEAU- UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE-UPPER GUNNISON RIVER VALLEY- UPPER YAMPA RIVER BASIN-WEST ELK AND SAWATCH MOUNTAINS- 837 AM MDT MON AUG 1 2005 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT... SCATTERED SHOWERS AND THUNDERSTORMS...NUMEROUS IN NORTHEAST UTAH MOUNTAINS...ARE POSSIBLE THIS AFTERNOON AND EVENING. HEAVY RAIN AND LIGHTNING WILL BE THE MAIN HAZARDS ACCOMPANYING THESE STORMS. SOME STORMS MAY PRODUCE FLOOD HAZARDS...ESPECIALLY IN AREAS THAT HAVE RECEIVED HEAVY RAIN DURING THE PAST 24 HOURS. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY... SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE EACH AFTERNOON AND EVENING. LIGHTNING AND HEAVY RAIN MAY OCCUR WITH THESE THUNDERSTORMS. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT. CJC
The radar
The Grand Junction radar (KGJX), 113 km away, was scanning. The volume nearest the first event began at 22:08 UTC.
Event by event
1 flash flood. Local standard time, as filed.
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
- Drought in Texas, August 1 to 31, 2005
- Drought in Iowa, August 1 to 31, 2005
- Drought in Illinois, August 1 to 31, 2005
- Drought in Missouri, August 1 to 31, 2005
- Tornado and Hail in New York, August 1, 2005
- Lightning Strike in New Hampshire, August 1, 2005
- Lightning Strike in North Carolina, August 1, 2005
- Damaging Winds in Vermont, August 1, 2005
- Lightning Strike in Louisiana, August 1, 2005
- Flash Flood in Arizona, August 1, 2005
- Damaging Wind and Lightning Strikes in Massachusetts, August 1 to 2, 2005
- Lightning Strike in North Carolina, August 1, 2005
More
Every storm in Utah in 2005Every state in 2005This day in weather historyWarnings in Utah, 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: 5471560.