Severe thunderstorms produced nickel size hail and strong winds across parts of Arapahoe, Elbert, Morgan and Weld Counties. Lightning struck a teenager in Littleton and sparked a grass fire in Golden.
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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.
Severe thunderstorms produced nickel size hail and strong winds across parts of Arapahoe, Elbert, Morgan and Weld Counties. Lightning struck a teenager in Littleton and sparked a grass fire in Golden. Four tornadoes reportedly touched down in Arapahoe, Elbert and Morgan Counties. One of the tornadoes destroyed a small barn and damaged a home near Brush.
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 Aug 16, 1:58 AM MST, 8 hours 40 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER CO 258 AM MDT MON AUG 16 2010 .SHORT TERM...AN UPPER LEVEL TROUGH WILL MOVE ACROSS THE AREA LATER THIS AFTN AND TONIGHT ALONG WITH SOME MID LEVEL QG ASCENT. ALTHOUGH SOUNDINGS SHOW A CAP ACROSS ALL OF NERN CO THIS AFTN AS MINOR COOLING ALOFT IN ASSOCIATION WITH UPPER LEVEL TROUGH COMES IN THIS SHOULD ERODE CAP BY MID TO LATE AFTN. MEANWHILE SFC LOW PRESSURE IS FCST TO BE JUST EAST OF DENVER BY EARLY AFTN WITH A CONVERGENCE ZONE SETTING UP FM FORT MORGAN TO LIMON. AS A RESULT BEST CHC OF TSTMS MAY END UP EAST OF THE FRONT RANGE URBAN CORRIDOR OVER THE PLAINS BY LATE AFTN. HOWEVER WITH DECENT INSTABILITY OVER MUCH OF THE AREA AND INCREASING QG ASCENT SCT TSTMS COULD DEVELOP JUST ABOUT ANYWHERE THRU THE EVENING HOURS. AS FAR AS SVR POTENTIAL MID LVL WINDS ARE FCST TO BE WEAKER TODAY HOWEVER WITH SOME COOLING ALOFT MAY SEE A FEW STORMS PRODUCE SOME HAIL. HIGHS TODAY OVER NERN CO WILL LOOKS TO BE A FEW DEGREES COOLER BASED ON 850-700 MB TEMPS. FOR TONIGHT AS MAIN UPPER LEVEL TROUGH MOVES ACROSS TSTMS WILL CONTINUE OVER THE PLAINS WITH SOME HEAVY RAINFALL POSSIBLE IF TRAINING OF CELLS OCCURS ALONG CONVERGENCE ZONE AS TALKED ABOUT ABOVE. ELSEWHERE EXPECT SOME LINGERING TSTMS IN THE MTNS AND ALONG THE FRONT RANGE THRU THE EARLY EVENING HOURS BEFORE ENDING. .LONG TERM...AFTER MONDAY NIGHTS PRECIPITATION COMES TO AN END...DRIER AND WARMER WEATHER WILL DOMINATE THE WEATHER PICTURE FOR MOST OF THE WEEK. HEIGHTS WILL BE RISING ALONG WITH LOWER AND MID-LEVEL TEMPERATURES. SUBSIDENCE ASSOCIATED WITH THE BUILDING RIDGE ON TUESDAY MAY INHIBIT THE DEVELOPMENT OF ANY SHOWERS TUESDAY AFTERNOON...DEPENDING ON HOW MUCH MOISTURE IS LEFT IN THE AIRMASS FROM MONDAY. FORECAST HAS 10 AND 20 PERCENT POPS TUESDAY AFTERNOON AND EVENING WHICH CAN BE REMOVED LATER IF LATER MODEL RUNS SHOW THE AIRMASS WILL BE TOO DRY TO SUPPORT SHOWERS. WEDNESDAY LOOKS LIKE IT WILL BE DRY AND VERY WARM AS THE RIDGE AXIS MOVES FROM THE MOUNTAINS OUT OVER THE PLAINS. THURSDAY MAY SEE ROUND OF AFTERNOON AND EVENING CONVECTION FROM A PASSING SHORT WAVE EMBEDDED IN THE ZONAL FLOW ALOFT WHICH MIGHT ALSO TAP INTO A BIT OF SUBTROPICAL MOISTURE ROTATING UP FROM MEXICO. AFTER THAT...ANOTHER RIDGE POPS UP OVER THE STATE FOR THE WEEKEND. THE ECMWF AND GFS BOTH AGREE THAT THE WEEKEND PERIOD COULD BE DRY DUE TO THE UPPER RIDGE OVER THE SOUTHERN TIER OF THE U.S. EXTENDING OUT TO THE SOUTHWEST OF CALIFORNIA. THAT PATTERN WOULD EFFECTIVELY CUT OFF ANY MONSOONAL MOISTURE COMING OUT OF MEXICO. MADE VERY FEW CHANGES TO THE FORECAST PACKAGE...SINCE MOST OF IT WAS ALREADY COVERED BY THE PREVIOUS FORECASTER. && .AVIATION...SFC LOW WAS CURRENTLY OVER DENVER BUT IS EXPECTED TO MOVE EAST OF DENVER BY LATE MORNING. STRATUS WAS DEVELOPING OVER THE PLAINS AND NR FORT COLLINS. ITS POSSIBLE SOME OF THIS STRATUS COULD WRAP AROUND SFC LOW TOWARDS SUNRISE AND AFFECT THE AIRPORT FOR AN HOUR OR TWO WITH IFR CONDITIONS. FOR LATER TODAY AM NOT SURE ABOUT TSTM COVERAGE AS MAIN CONVERGENCE ZONE WILL BE EAST OF THE AIRPORT THIS AFTN. HOWEVER WITH DECENT INSTABILITY AND APPROACHING UPPER LEVEL TROUGH SCT TSTMS COULD DEVELOP JUST ABOUT ANYWHERE AFTER 21Z THRU 02Z. IF A STORM DOES AFFECT THE AIRPORT COULD SEE BRIEF MVFR CONDITIONS DUE TO HEAVY RAIN. WINDS TODAY WILL BE DEPENDANT ON LOCATION OF MAIN SFC LOW. RIGHT NOW IF LOW ENDS UP BEING EAST OF THE AIRPORT THEN WINDS SHOULD HAVE A NNE COMPONENT FROM LATE MORNING THROUGH THE AFTN HOURS. && .BOU WATCHES/WARNINGS/ADVISORIES...NONE. RPK/KDRBY
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DENVER CO 1036 AM MDT MON AUG 16 2010 COZ030>051-171200- 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- 1036 AM MDT MON AUG 16 2010 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL DEVELOP TODAY AND BECOME MORE NUMEROUS OVER THE PLAINS OF NORTHEAST COLORADO THIS EVENING AS AN UPPER LEVEL TROUGH MOVES ACROSS THE AREA. A FEW OF THE STORMS MAY BECOME SEVERE OVER NORTHEAST COLORADO WITH LARGE HAIL AND STRONG WINDS. IN ADDITION SOME HEAVY RAINFALL WILL ALSO OCCUR OVER THE PLAINS WITH A FEW INCHES POSSIBLE. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY TUESDAY AND WEDNESDAY WILL HAVE VERY LITTLE CONVECTIVE ACTIVITY COMPARED TO MONDAY AS AN UPPER RIDGE BUILDS OVERHEAD. ANOTHER SHORTWAVE WEDNESDAY NIGHT THROUGH THURSDAY WILL INCREASE SHOWER AND THUNDERSTORM COVERAGE...HOWEVER NO HAZARDOUS WEATHER IS EXPECTED. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE NEEDED THIS AFTERNOON AND EVENING. MEIER/KRIEDERMAN
The Denver radar (KFTG), 58 km away, was scanning. The volume nearest the first event began at 17:39 UTC.
4 tornado, 3 lightning, 1 hail, 1 thunderstorm wind. Local standard time, as filed.
A lightning strike sparked a small grass fire near Quaker Street and Golden Road. It was quickly extinguished by emergency responders.
A 14-year-old teenager was struck by lightning while washing her family's car. The bolt struck the street nearby; it then traveled up a stream of water flowing from the vehicle and hit the teenager. She received minor injuries.
Lightning struck a tree in Morrison.
A tornado touched down briefly but did no damage.
A tornado touched down briefly but did no damage.
A tornado touched down briefly but did no damage.
A tornado touched down near a home. It uprooted trees and did some damage to the home, breaking windows some windows. Two horse trailers were picked up and thrown approximately 100 yards. Several hundred yards of fence were torn out of the ground, and several wood and steel fence posts were torn out of the ground. Debris was found up to a mile from where the tornado touched down. A small horse barn that had been recently built was also destroyed; one horse was badly injured and was later euthanized.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2010Every state in 2010This day in weather historyThe tornado archive for Colorado, 2010Warnings in Colorado, August 2010
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: 252461, 252460, 252462, 252439, 252437, 252440, 252441, 252442, 252443.