1 flash flood, as filed by the National Weather Service.
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.
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 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 Denver/Boulder, CO wrote its last area forecast discussion before the first event at Jul 18, 1:30 PM MST, 2 hours earlier.
AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE DENVER CO 230 PM MDT SUN JUL 18 2004 .SHORT TERM DISCUSSION... DRYING HAS CONTINUED TO INTRUDE INTO NORTHEAST COLORADO IN THE PAST 24 HOURS...AND THIS WILL LIMIT CONVECTION ON THE NORTHEAST PLAINS. THE MODELS SHOW MID LEVEL THETA-E RIDGES OVER THE MOUNTAINS AND WEST...MAINLY FROM THE CONTINENTAL DIVIDE WESTWARD. THERE IS A 700 MB THETA E RIDGE AND BETTER CAPE OVER LINCOLN COUNTY. WILL RAISE POPS A BIT OVER ZNS 46 AND 47...AND REDUCE POPS A BIT IN FOOTHILLS GIVEN THE MOISTURE/ INSTABILITY DEPLOYMENT ACROSS THE CWA. MAY GET A FEW THUNDERSTORMS THAT MAKE IT TO THE URBAN CORRIDOR...BUT DO NOT EXPECT THEM TO LIVE LONG. PRECIPITOUS FALL IN DEWPOINTS AT FNL MID AFTERNOON CAUSE ME TO BELIEVE THERE WILL BE NO THUNDERSTORMS THERE THIS EVENING. DROPPED ALL MENTION OF TSTMS THERE...MAY STILL SEE SOME BOUNDARIES AROUND METRO DENVER KICK UP A STORM OR TWO. CONVECTIVE DEBRIS WILL SLOWLY ERODE OVERNIGHT...WITH MOSTLY SUNNY SKIES ON THE PLAINS MONDAY MORNING. A SURFACE TROF PULLING INTO THE DAKOTAS ON MONDAY WILL BRING A THERMAL RIDGE ACROSS THE NORTHEAST PLAINS MONDAY AFTERNOON. MOISTURE WILL AGAIN RESIDE OVER THE HIGHER TERRAIN...AND THAT IS WHERE THE BEST CHANCE OF THUNDERSTORMS WILL BE. EXPECT A FEW STORMS TO MAKE IT OFF THE FOOTHILLS...BUT ONLY AS FAR AS THE URBAN CORRIDOR. .LONG TERM DISCUSSION...NO SUBSTANTIAL CHANGES EXPECTED IN THE MONDAY NIGHT THROUGH TUESDAY NIGHT TIME FRAME WITH UPPER RIDGE AND SOME MOISTURE PERSISTING OVER THE REGION. THIS SHOULD LEAD TO A TYPICAL SUMMER TIME/CLIMATOLOGICAL PATTERN OF TEMPERATURES AND AFTERNOON AND EVENING CONVECTION. FOR THE WEDNESDAY THROUGH SUNDAY TIME FRAME THE MODELS ARE PRETTY CONSISTENT IN FLATTENING THE RIDGE OVER COLORADO AS AN UPPER WAVE PASSES OVER THE NORTHERN ROCKIES WEDNESDAY AND EARLY THURSDAY. THIS SYSTEM SHOULD BE SUFFICIENT TO SEND A COOL...LOW LEVEL HIGH PRESSURE SYSTEM INTO THE PLAINS OF COLORADO BY THURSDAY. THEREAFTER THE RIDGE POPS UP AGAIN TO OUR WEST WITH NORTHWEST FLOW ALOFT OVER THE DISTRICT WHICH WILL KEEP THE DOOR OPEN TO COOL NORTHERLY SURGES FROM TIME TO TIME. THUS THE MAIN MESSAGE FOR THE LATER HALF OF THE WEEK WILL BE COOLER TEMPERATURES...ESPECIALLY ON THE PLAINS. REGARDING CONVECTION LATER IN THE WEEK THE TRICKY PART WILL BE HOW CLOUDY/ COOL/STABLE WE MAY BE...ESPECIALLY THURSDAY AND FRIDAY. THERE MAY BE LITTLE IN THE WAY OF SHOWER/THUNDERSTORM ACTIVITY ON THE PLAINS THURSDAY AND FRIDAY WITH A BETTER CHANCE OVER THE WEEKEND AS THERE WOULD LIKELY BE LESS STABILITY AROUND BY THEN. HOWEVER...THE HIGH COUNTRY SHOULD BE ABLE TO SEE CONVECTION EACH DAY. THESE DETAILS IN THE CONVECTION TREND ARE TOUGH TO FORECAST THIS FAR OUT SO FEEL BEST FORECAST AT THIS POINT IS THE GOING ONE. && .BOU WATCHES/WARNINGS/ADVISORIES...NONE. && RTG/ET
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DENVER CO 1115 AM MDT SUN JUL 18 2004 COZ030>051-191200- JACKSON COUNTY BELOW 9000 FEET-WEST JACKSON AND WEST GRAND COUNTIES ABOVE 9000 FEET-GRAND AND SUMMIT COUNTIES BELOW 9000 FEET-SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/ NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-SOUTH AND SOUTHEAST GRAND/WEST CENTRAL AND SOUTHWEST BOULDER/GILPIN/CLEAR CREEK/ SUMMIT/NORTH AND WEST PARK COUNTIES ABOVE 9000 FEET-LARIMER AND BOULDER COUNTIES BETWEEN 6000 AND 9000 FEET-JEFFERSON AND WEST DOUGLAS COUNTIES ABOVE 6000 FEET/GILPIN/CLEAR CREEK/NORTHEAST PARK COUNTIES BELOW 9000 FEET-CENTRAL AND SOUTHEAST PARK COUNTY-LARIMER COUNTY BELOW 6000 FEET/NORTHWEST WELD COUNTY-BOULDER AND JEFFERSON COUNTIES BELOW 6000 FEET/WEST BROOMFIELD COUNTY-NORTH DOUGLAS COUNTY BELOW 6000 FEET/DENVER/WEST ADAMS AND ARAPAHOE COUNTIES/ EAST BROOMFIELD COUNTY-ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES ABOVE 6000 FEET-NORTHEAST WELD COUNTY-CENTRAL AND SOUTH WELD COUNTY-MORGAN COUNTY-CENTRAL AND EAST ADAMS AND ARAPAHOE COUNTIES- NORTH AND NORTHEAST ELBERT COUNTY BELOW 6000 FEET/NORTH LINCOLN COUNTY-SOUTHEAST ELBERT COUNTY BELOW 6000 FEET/SOUTH LINCOLN COUNTY-LOGAN COUNTY-WASHINGTON COUNTY-SEDGWICK COUNTY-PHILLIPS COUNTY- 1115 AM MDT SUN JUL 18 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL ONCE AGAIN ERUPT OVER THE HIGH COUNTRY TODAY...WITH ISOLATED THUNDERSTORMS OVER THE PALMER DIVIDE AND URBAN CORRIDOR. IT LOOKS TOO STABLE TO DEVELOP THUNDERSTORMS ON THE PLAINS. WITH WEAK STEERING WINDS THUNDERSTORMS WILL MOVE SLOWLY... AND LOCALLY HEAVY RAIN IS POSSIBLE...BUT THE AIRMASS IS SLIGHTLY DRYER AND FLOODING POTENTIAL A BIT LOWER. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.
The Denver radar (KFTG), 95 km away, was scanning. The volume nearest the first event began at 22:31 UTC.
1 flash flood. Local standard time, as filed.
Heavy rain again caused flash flooding over parts of Virginia Canyon Road near Idaho Springs. Several sections of the roadway were washed out. As a result, the road had to be closed temporarily for repairs.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2004Every state in 2004This day in weather historyWarnings in Colorado, July 2004
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: 5417173.