Damaging downslope winds developed along the Front Range and spread into the adjacent plains. Peak wind gusts approached 100 mph along the foothills of Boulder and Larimer Counties.
Every event with a place to put it; 8 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 episode as NWS BOU wrote it up.
Damaging downslope winds developed along the Front Range and spread into the adjacent plains. Peak wind gusts approached 100 mph along the foothills of Boulder and Larimer Counties. In Superior, a 1,200 square foot section of roof was peeled off the gymnasium at Monarch High School. Two semi-trailers were toppled on Colorado Highway 58 and McIntyre Street and another at C-470 and West Bowles Avenue. Two planes were also damaged by debris at Jefferson County Airport. Strong winds forced the closure of State Highway 93, between Golden and Boulder, for approximately two hours. Insurance agents estimated 650 to 850 homes suffered wind damage in the Boulder and Louisville areas. In addition, downed trees and power lines left approximately 10000 residents, mainly in the Boulder area without electricity. At least three people suffered minor injuries in the storm.Peak wind reports included: 98 mph (85 kts) at Carter Lake, 95 mph (82 kts) at Superior, 92 mph (80 kts) at Jefferson County Airport, 85 mph (74 kts) at Golden, 81 mph (70 kts) in Boulder, 80 mph (69 kts) at Broomfield and Evergreen, 79 mph (69 kts) at Louisville, 72 mph (63 kts), 4 miles east of Haxtun and Merino, 67 mph (58 kts) at Haxtun, 64 mph (56 kts) at Fort Morgan, 62 mph (54 kts) at Akron, 60 mph at (52 kts) at Crook and 59 mph (51 kts) at Denver International Airport.
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 Dec 19, 2:28 PM MST, 10 hours 2 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER CO 228 PM MST SUN DEC 19 2004 .SHORT TERM...MAIN CONCERN TONIGHT IS POTENTIAL FOR HIGH WIND FOR MOUNTAINS AND FOOTHILLS. NORTHWEST FLOW ALOFT INCREASES AS UPPER LEVEL JET CORE SLIDES ACROSS WYOMING. LATEST MODEL CROSS SECTIONS INDICATE CROSS BARRIER MOUNTAIN COMPONENT INCREASES TO 50 KTS AFTER 06Z. THIS...HOWEVER...IS LESS THAN WHAT PREVIOUS RUNS INDICATED ALTHOUGH THE SHEAR ALOFT AND STABILITY PROFILE IMPROVES A BIT. FORECAST SANGSTER DATA USING ETA12 INDICATES LOW PROBABILITY OF WINDS REACHING HIGH WIND CRITERIA...THOUGH SHOWS 27% CHANCE OF WINDS GREATER THAN 60 KTS. SO...IT DOESNT APPEAR THAT WINDS WILL REACH HIGH WIND CRITERIA ON A WIDESPREAD BASIS AND WILL NOT ISSUE A WATCH. GOING FORECAST HAS STRONG WINDS ALREADY MENTIONED IN MOUNTAINS AND FOOTHILLS...WILL INCREASE THEM A BIT. DOWNSLOPE COMPONENT SHOULD KEEP TEMPERATURES RATHER MILD ALONG FOOTHILLS... WHICH IS SHOWN NICELY IN CURRENT TEMPERATURE GRIDS. WINDS WILL BEGIN TO SLACKEN DURING MORNING HOURS MONDAY AS JET MAX PULLS AWAY FROM AREA. CROSS BARRIER MOUNTAIN COMPONENT DECREASES TO 40 KTS BY 18Z. SOME MEAGER MOISTURE BEGINS TO INCREASE OVER MOUNTAINS AFTER 18Z IN RESPONSE TO UPPER TROUGH APPROACHING AREA. DOESNT APPEAR TO BE ENOUGH TO WARRANT POPS...BUT WILL LEAVE THE LOW MOUNTAIN POPS AS DIV-Q VERTICAL VELOCITY FORECASTS SHOW SOME WEAK LIFT DURING AFTERNOON. IN ALL...LITTLE CHANGE TO ONGOING GRIDS. .LONG TERM...SHORT AND MEDIUM RANGE MODELS CONTINUE TO OSCILATE WITH IN THE TIMING AND TRAJECTORY OF ARCTIC AIR AIRMASS PLUNGING SOUTH OUT OF CENTRAL CANADA LATER THIS WEEK. GETTING A HANDLE ON THE MODELS AND DECIDING WHICH MODEL OR RUN TO USE HAS BEEN A REAL CHALLENGE THE LAST FEW DAYS. GFS...CANADIAN AND ECMWF MODELS HAVE SLOSHED THE COLD AIR BACK AND FORTH IN RESPONSE TO THE MOVEMENT OF THE BIG WEST COAST TROUGH. MODELS NOW SHOWING THE MAIN PUSH OF COLD/ARCTIC AIR INTO THE CENTRAL PLAINS AND GREAT LAKES REGION. SOME OF THIS COLD AIR APPEARS TO BACK INTO NERN COLORADO AS TWO SURGES... THE FIRST ARRIVING SOMETIME MONDAY NIGHT OR EARLY TUESDAY MORNING AND THE SECOND WEDNESDAY AFTERNOON OR EVENING. THE EXACT TIMING AND INTENSITY STILL QUITE UNCERTAIN AS THE EDGE OF REALLY COLD AIR REMAINS JUST BEYOND THE NORTHEAST CORNER OF COLORADO THROUGH THURSDAY NIGHT. MEANWHILE LIFT AND INSTABILITY ASSOCIATED WITH PASSING JET IS EXPECTED TO PRODUCE SOME ACCUMULATING SNOWFALL IN THE NRN MTNS TUESDAY THROUGH THURSDAY. HEAVIEST ACCUMULATIONS APPEAR TO OCCUR TUESDAY WITH AMOUNTS ON THE ORDER OF 2 TO 4 INCHES. SNOWFALL CHANCES NOT LOOKING ALL THAT GREAT ELSEWHERE. SEE A CHANCE FOR LIGHT SNOW MONDAY NIGHT...TUESDAY AND WEDNESDAY NIGHT WITH PASSAGE OF COLD FRONTS. WEAK OROGRAPHIC LIFT SHOULD CONFINE ANY ACCUMULATIONS... ALBEIT LIGHT...TO HIGHER AREAS IN AND NEAR THE FRONT RANGE FOOTHILLS AND PALMER DIVIDE. AS FOR TEMPERATURES...HAVE MADE VERY FEW CHANGES...ALTHOUGH HAVE ADJUSTED TEMPS UPWARD FRIDAY...SATURDAY AND SUNDAY AS MODELS ARE NOW SHOWING THE COLD AIR MOVING OUT SOONER. FURTHERMORE...WITH HIGH PRESSURE BUILDING IN FROM THE WEST...COULD SEE TEMPERATURES ON THE PLAINS RETURNING TO THE 50S BY CHRISTMAS DAY. HOPES FOR A WHITE CHRISTMAS MAY BE DASHED SHOULD THIS OCCUR... ESPECIALLY IN BREEZY AREAS ALONG THE FOOTHILLS. .BOU WATCHES/WARNINGS/ADVISORIES...NONE. && D-L/BAKER
HAZARDOUS WEATHER OUTLOOK...DELAYED NATIONAL WEATHER SERVICE DENVER CO 1116 AM MST SUN DEC 19 2004 COZ030>051-201300- 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- 1116 AM MST SUN DEC 19 2004 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT GUSTY NORTHWEST WINDS WILL CONTINUE TO DEVELOP OVER THE HIGH COUNTRY THIS AFTERNOON. WINDS OF 25 TO 35 MPH WILL BE COMMON...WITH SOME GUSTS TO 60 MPH POSSIBLE. THE WINDS ARE EXPECTED TO INCREASE TONIGHT...WITH SOME GUSTS REACHING 70 MPH OVER THE HIGHER EXPOSED RIDGES AND ALONG THE EAST SLOPES AFTER MIDNIGHT. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY UNSEASONABLY MILD TEMPERATURES AREAWIDE AND GUSTY WEST WINDS IN THE MOUNTAINS AND FOOTHILLS WILL GIVE WAY TO SIGNIFICANTLY COLDER AND CLOUDY CONDITIONS MONDAY NIGHT OR EARLY TUESDAY MORNING FOLLOWING PASSAGE OF A STRONG COLD FRONT. A SECOND REINFORCING SURGE OF COLD CANADIAN AIR IS FORECAST TO PUSH UP AGAINST THE FRONT RANGE SOME TIME WEDNESDAY NIGHT. WITH EACH SURGE OF COLD AIR THERE WILL BE A CHANCE OF LIGHT UPSLOPE SNOWFALL IN THE MOUNTAINS...FRONT RANGE FOOTHILLS AND IN PORTIONS OF THE I-25 URBAN CORRIDOR. THE EXACT TIMING AND DURATION OF THIS SNOWFALL IS UNCERTAIN. HOWEVER IT DOES APPEAR ANY ACCUMULATIONS WILL BE LIGHT. NOTICEABLY WARMER AND DRIER CONDITIONS ARE FORECAST TO RETURN TO THE OUTLOOK AREA EITHER BY LATE FRIDAY OR CHRISTMAS DAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT. D-L/MRB
The national radar mosaic for the moment the first event began.
8 high wind. Local standard time, as filed.
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, December 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: 5429071, 5429072, 5429073, 5429074, 5429075, 5429076, 5429077, 5429078.