The active monsoon pattern continued to bring heavy rainfall to portions of western Colorado. After several consecutive days of heavy rainfall, more flash flooding and debris flows were reported during the afternoon and evening hours when thunderstorms were at their peak intensity.
Every event with a place to put it. Tap one for its entry below.
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.
The episode as NWS GJT wrote it up.
The active monsoon pattern continued to bring heavy rainfall to portions of western Colorado. After several consecutive days of heavy rainfall, more flash flooding and debris flows were reported during the afternoon and evening hours when thunderstorms were at their peak intensity.
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 Jul 18, 2:01 PM MST, 2 hours 24 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 301 PM MDT THU JUL 18 2013 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 300 PM MDT THU JUL 18 2013 SLOW MOVING THUNDERSTORMS CONTINUE TO DEVELOP THIS AFTERNOON. THE MAIN STORM THREAT...BESIDES LIGHTNING...IS LOCALLY RAIN (SEE HYDROLOGY SECTION). SATELLITE ESTIMATED PRECIPITABLE WATER TO BE AROUND 1 INCH. STORMS WERE A BIT SLOW IN GETTING GOING ACROSS THE NORTH EARLY IN AFTERNOON WHERE SPC MESOSCALE ANALYSIS STILL SHOWED SOME CONVECTIVE INHIBITION PRESENT BUT DWINDLING AT 20Z. MOISTURE PLUME AND SHEAR AXIS WERE EVIDENT IN SATELLITE FROM SRN UT ACROSS NW CO. ON RADAR...STORMS SOUTH OF INTERSTATE 70 WERE GENERALLY EXHIBITING A SLOW SOUTHWESTWARD MOTION... WHILE THOSE TO THE NORTH OF I-70 WERE DRIFTING MORE TO THE EAST OR SOUTHEAST. SIMILAR TO YESTERDAY...EXPECT THE SHOWERS AND STORMS TO PERSIST THROUGH EVENING BEFORE DECREASING OVERNIGHT. MOIST AND UNSTABLE AIR WILL REMAIN OVER ERN UT/WRN CO THROUGH FRIDAY AS THE MOISTURE PLUME BECOMES MORE EAST-WEST ORIENTED ACROSS THE CENTRAL AND SOUTH. THE OCCURS AS AN UPPER HIGH BECOMES MORE PRONOUNCED OVER NEVADA...AND A LARGE TROUGH BEGINS TO DEVELOP SOUTHWARD ACROSS THE GREAT LAKES. PRECIPITABLE WATER REMAINS AROUND 1 INCH FOR THE CONTINUED THREAT OF LOCALLY HEAVY RAIN. A LITTLE DRIER AIR WILL BEGIN SNEAKING INTO NE UT FRI NIGHT AS THE PATTERN BEGINS TO CHANGE. LITTLE CHANGE IN TEMPERATURE IS EXPECTED. PERSISTENCE LOOKS LIKE THE BEST INITIAL GUIDANCE THROUGH FRIDAY NIGHT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 300 PM MDT THU JUL 18 2013 A DOWNTURN OF THE SEASONAL THUNDERSTORM AND SHOWER ACTIVITY IS EXPECTED THROUGH WEDNESDAY WITH SHOWERS AND STORMS INCREASING AGAIN NEXT THURSDAY. INTO EARLY NEXT WEEK THE UPPER HIGH WILL BE STRETCHED FROM NORTHERN CALIFORNIA TO OKLAHOMA...WITH AN INVERTED TROUGH IN NORTHERN BAJA. A N-NW FLOW ALOFT ADVECTS IN DRIER AIR ACROSS THE NORTHERN AND CENTRAL ZONES ON SATURDAY AND DOWN TO NEAR THE FOUR CORNERS ON SUNDAY. PRECIPITABLE WATER VALUES...THAT HAVE BEEN OVER AN INCH FOR THE LAST SEVERAL DAYS..IS PROGGED TO DROP TO NEAR 0.25 INCH NORTH AND NEAR 0.70 INCH ALONG THE NM/AZ BORDER. THIS DRIER AIR REMAINS IN PLACE INTO WEDNESDAY. DIURNAL TEMPERATURE SPREAD WILL INCREASE IN THE DRIER AIR MASS WITH THE LOWER VALLEYS OF UTAH AND FAR WESTERN COLORADO THREATENING TRIPLE DIGIT AFTERNOONS AGAIN. DEWPOINTS IN THE 20-30S ALONG AND NORTH OF I-70 WILL HELP EVAPORATIVE COOLERS TO WORK MORE EFFICIENTLY. WEDNESDAY...THERE IS GOOD MODEL AGREEMENT THAT THE UPPER HIGH BEGINS TO SHIFT TO SOUTH CENTRAL COLORADO...THEN ONTO THE SOUTHERN PLAINS ON THURSDAY. MEANWHILE THE NORTHERN BAJA LOW BEGINS TO LIFT NE INTO THE GREAT BASIN BRINGING SUBTROPICAL MOISTURE WITH IT. THIS DEEPER MOISTURE AND INCREASED THUNDERSTORM POTENTIAL IS CURRENTLY TIMED TO SPREAD INTO EASTERN UTAH WEDNESDAY NIGHT THEN WESTERN COLORADO ON THURSDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 300 PM MDT THU JUL 18 2013 SHOWERS AND THUNDERSTORMS DEVELOPING OVER THE HIGHER TERRAIN THIS AFTERNOON WILL CONTINUE THROUGH 04Z BEFORE GRADUALLY BEGINNING TO DECREASE. THERE IS A CHANCE THAT ALL TAF SITES WILL EXPERIENCE BRIEF MVFR VSBY FROM THUNDERSTORMS BEARING HEAVY RAIN. THE STRONGEST CELLS WILL BE CAPABLE OF GENERATING BRIEF IFR VSBY. EXPECT MOUNTAIN OBSCURATIONS AT TIMES FROM THE STORMS. FRIDAY SHOULD BE SIMILAR TO TODAY. && .HYDROLOGY... ISSUED AT 300 PM MDT THU JUL 18 2013 SLOW MOVING THUNDERSTORM AND MOISTURE-RICH AIR WILL KEEP THE THREAT OF LOCALLY HEAVY RAIN PRESENT THROUGH FRIDAY. WITHOUT AN OBVIOUS SHORTWAVE TRIGGER...IT MAY BE DIFFICULT TO PINPOINT AREAS MUCH IN ADVANCE OTHER THAN STORMS DEVELOPING FIRST OVER THE MOUNTAINS ON FRIDAY. THEREFORE...WILL HAVE TO MONITOR STORMS CLOSELY FOR THE POTENTIAL EXCESSIVE RAINFALL/RUNOFF ONCE THEY FORM. SOME AREAS THAT MAY BE MORE PRONE TO RUNOFF PROBLEMS WILL BE THOSE LOCATIONS THAT HAVE ALREADY RECEIVED HEAVIER RAIN...SUCH AS THE PICEANCE BASIN...ERN TAVAPUTS PLATEAU IN UT...AND THE TELLURIDE/SAWPIT AREAS. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...NONE. UT...NONE. && SHORT TERM...JAD LONG TERM...JOE AVIATION...JAD HYDROLOGY...JAD
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE GRAND JUNCTION CO 545 AM MDT THU JUL 18 2013 COZ001>014-017>023-UTZ022>025-027>029-191145- LOWER YAMPA RIVER BASIN-CENTRAL YAMPA RIVER BASIN- ROAN AND TAVAPUTS PLATEAUS-ELKHEAD AND PARK MOUNTAINS- UPPER YAMPA RIVER BASIN-GRAND VALLEY-DEBEQUE TO SILT CORRIDOR- CENTRAL COLORADO RIVER BASIN-GRAND AND BATTLEMENT MESAS- GORE AND ELK MOUNTAINS/CENTRAL MOUNTAIN VALLEYS- CENTRAL GUNNISON AND UNCOMPAHGRE RIVER BASIN- WEST ELK AND SAWATCH MOUNTAINS-FLATTOPS- UPPER GUNNISON RIVER VALLEY-UNCOMPAHGRE PLATEAU AND DALLAS DIVIDE- NORTHWEST SAN JUAN MOUNTAINS-SOUTHWEST SAN JUAN MOUNTAINS- PARADOX VALLEY/LOWER DOLORES RIVER- FOUR CORNERS/UPPER DOLORES RIVER-ANIMAS RIVER BASIN- SAN JUAN RIVER BASIN-SOUTHEAST UTAH-EASTERN UINTA MOUNTAINS- EASTERN UINTA BASIN-TAVAPUTS PLATEAU-ARCHES/GRAND FLAT- LA SAL AND ABAJO MOUNTAINS-CANYONLANDS/NATURAL BRIDGES- 545 AM MDT THU JUL 18 2013 THIS HAZARDOUS WEATHER OUTLOOK IS FOR EASTERN UTAH AND WESTERN COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL DEVELOP ACROSS THE AREA LATE THIS MORNING AND WILL CONTINUE WELL INTO THE EVENING. VERY HEAVY RAINFALL IS POSSIBLE WITH THE STRONGEST CELLS WHICH COULD LEAD TO LOCALIZED FLOODING. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE POSSIBLE AGAIN FRIDAY AFTERNOON AND EVENING. SATURDAY WILL SEE THE MAIN FOCUS OF SHOWERS AND THUNDERSTORMS CONFINED TO CENTRAL AND SOUTHWEST COLORADO AND SOUTHEAST UTAH. AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DECREASE SUNDAY INTO TUESDAY AS DRIER AIR FILTERS ACROSS THE AREA FROM THE NORTH. MONSOON MOISTURE MAY RETURN TO THE SOUTH WEDNESDAY BRINGING AN UPTICK IN AFTERNOON AND EVENING THUNDERSTORM ACTIVITY TO HIGH COUNTRY SOUTH OF THE I-70 CORRIDOR. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED TODAY OR TONIGHT...HOWEVER SPOTTERS ARE ENCOURAGED TO RELAY RAINFALL AMOUNTS OR ANY OBSERVED FLOODING TO THE GRAND JUNCTION FORECAST OFFICE. NL/CC
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
426 PM MDT THU JUL 18 2013
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0417 PM DEBRIS FLOW 2 E MINTURN 39.58N 106.39W
07/18/2013 EAGLE CO DEPT OF HIGHWAYS
HWY 24 CLOSED IN BOTH DIRECTIONS AT MM 148 DUE TO
MUDSLIDE
&&
EVENT NUMBER GJT1301242
TBThe Grand Junction radar (KGJX), 15 km away, was scanning. The volume nearest the first event began at 23:23 UTC.
4 debris flow, 3 flash flood, 1 hail, 1 heavy rain. Local standard time, as filed.
Water and mud also flowed across Highway 65 in the area where the nickel-sized hail fell.
Heavy rainfall resulted in a number of mudslides that were reported on several county roads around De Beque.
Westbound Interstate 70 was closed for several hours near mile marker 46 due to a mudslide.
A total of 2.02 inches fell at this location within one hour.
Highway 50 was closed in both directions at mile markers 52-58 due to flash flooding. Fast moving water flowed up to two feet deep in places across the four lanes of the highway.
A Union Pacific train trestle was washed away, including the super and sub-structure. Portions of a dirt road between Highway 50 and the train tracks in Dominguez Canyon were washed out. The flow of rapidly moving water through this area was estimated to be up to 10 feet deep and 30 yards wide.
Flash flooding along Kannah Creek caused mud and boulders to wash into a yard and damage an access road.
Heavy rainfall resulted in a mudslide over Highway 141 near Uravan.
Heavy rainfall resulted in a mudslide across Highway 90 near the community of Bedrock.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2013Every state in 2013This day in weather historyWarnings in Colorado, July 2013
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: 510335, 510344, 510340, 512016, 510337, 510338, 510339, 510342, 510343.