Several severe thunderstorms developed east of the Interstate 25 corridor and in the Northeast Plains. Most of the storms produced damaging straightline winds.
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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.
Several severe thunderstorms developed east of the Interstate 25 corridor and in the Northeast Plains. Most of the storms produced damaging straightline winds. Hail, very heavy rainfall and one tornado were also reported. Most of the damage occurred in the city of Sterling.
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 5, 1:53 PM MST, 1 hour 37 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER CO 253 PM MDT SUN JUL 5 2009 .SHORT TERM...SHORTWAVE PASSING ACROSS WESTERN COLORADO...AS NOTED BY SATELLITE. SCATTERED CONVECTION CURRENTLY ACROSS MOUNTAINS AND FOOTHILLS...ONLY ISOLATED COVERAGE NOTED BY RADAR OVER THE PLAINS. EARLY AM SURGE STABILIZED MOST OF PLAINS...PARTICULARY ALONG FRONT RANGE. AIRMASS BEGINNING TO DESTABILIZE IN RESPONSE TO THE APPROACHING WAVE. SHOULD SEE STORM COVERAGE INCREASE ACROSS PLAINS AS WAVE MOVES THROUGH. WILL KEEP THE SCATTERED COVERAGE GOING. BEST INSTABILITY CURRENTLY ACROSS PALMER DIVIDE WHERE HEATING HAS BEEN MAXIMIZED WITH LAPS SURFACE ANALYSIS INDICATING CAPES FROM 1200-1700 J/KG. ELSEWHERE...CAPES GENERALLY AROUND 1000 J/KG. FAIRLY DECENT SHEAR WITH 30-35KTS OF MID LEVEL WINDS...THOUGH SURFACE WINDS STILL WEAK. SPC RECENTLY ISSUED SEVERE STORM WATCH FOR DOUGLAS... ELBERT AND LINCOLN COUNTIES THROUGH 02Z. ELSEWHERE...MAIN STORM THREAT WILL BE HEAVY RAIN AS PRECIPITABLE WATER VALUES HAVE CLIMBED TO AROUND NINE TENTHS. STORM MOTION AROUND 10-15KTS...SHOULD KEEP ANY ACTIVITY FROM LINGERING IN ONE SPOT. MODELS SHOW SHORTWAVE EAST OF THE AREA BY MIDNIGHT...WITH SUBSIDENCE AND SOME DRYING OVERNIGHT. WILL END STORMS AROUND MIDNIGHT WITH SOME CLEARING. SURFACE WIND PROGS SHOW DRAINAGE WINDS DEVELOPING DURING THE EVENING...SHOULD KEEP STATUS AND FOG FROM DEVELOPING. ON MONDAY...UPPER LEVEL RIDGE BEGINS TO BUILD ACROSS GREAT BASIN...SPREADING DRIER AIR ACROSS CWA. SOME DESTABILIZATION DURING AFTERNOON DESPITE WEAK SUBSIDENCE. ALTHOUGH PRECIPITABLE WATER VALUES EXPECTED TO DECREASE TO AROUND EIGHT TENTHS DURING AFTERNOON...STILL ENOUGH MOISTURE FOR SOME CONVECTION...MAINLY OVER THE MOUNTAINS AND ALONG PALMER DIVIDE. CURRENT POP AND WEATHER GRIDS ALREADY SHOW THIS TREND...SEE NO REASON TO CHANGE. FORECAST SOUNDINGS SHOW ENOUGH SHEAR FOR A FEW STORMS TO APPROACH SEVERE LIMITS ACROSS PLAINS...THOUGH CHANCES FOR SEVERE ACTIVITY STILL REMAIN LOW DUE TO WEAK LOW LEVEL WINDS. DESPITE THE DECREASE IN PRECIPITABLE WATER...BRIEF HEAVY RAIN STILL A THREAT WITH THE STORMS. TEMPERATURE AND THICKNESS PROGS AS WELL AS GUIDANCE SUGGEST HIGHS WELL INTO THE 80S ACROSS PLAINS...WITH 70S MOUNTAINS. CURRENT TEMPERATURE GRIDS LOOK REASONABLE. .LONG TERM...NO MAJOR CHANGES IN THE FORCAST FOR THE UPCOMING WEEK. AN UPPER LEVEL RIDGE WILL BE OVER THE DESERT SOUTHWEST ON TUESDAY WITH A DRY WLY FLOW OVER CO. INTERACTIVE SOUNDINGS SHOW THE AMS DRYING OUT BUT STILL ENOUGH CAPE TO PRODUCE A FEW HIGH BASED TSTMS ON TUE. THE MID LEVEL WILL WARM ON WEDNESDAY AS THE RIDGE BUILD OVER AZ/NEW MX. BUFKIT SOUNDING HAVE ZERO VALUES FOR CAPE IN THE AFTN. WL KEEP TSTMS OUT ALTOGETHER ON WEDNESDAY. 700 MB TEMPS AROUND +16 TO +18C TUE THRU SAT...SO BASICALLY MID 90S THROUGH THE PERIOD. THERE MAY BE ENUF MSTR ALBEIT SPARSE UNDER THE RIDGE FOR A FEW TSTMS AT THE END OF THE WEEK SO WL KEEP THE MNTN OF SLGT CHC FOR THU-SUN. THE RIDGE ITSELF WL BE CENTERED OVER SRN CO/NRN NEW MX FOR SATURDAY AND SUNDAY. && .AVIATION...CHANCE FOR THUNDERSTORMS AFFECTING AREA AIRPORTS THROUGH ABOUT 04Z...WITH GUSTY OUTFLOW WINDS AROUND 35 KTS AND BRIEF HEAVY RAIN. MVFR CEILINGS AND VISIBILITIES POSSIBLE WITH THE PASSING STORMS...OTHERWISE VFR CONDITIONS PREVAILING. ALTHOUGH CEILINGS EXPECTED TO REMAIN VFR...GOOD CHANCE FOR ILS CONDITIONS THIS EVENING. DRAINAGE WINDS EXPECTED OVERNIGHT...WHICH SHOULD KEEP FOG FROM DEVELOPING AT AREA AIRPORTS. ON MONDAY...CHANCE FOR STORMS AFTER 18Z MAINLY ALONG FOOTHILLS AND PALMER DIVIDE. GUSTY OUTFLOW WINDS TO 40 KTS COULD AFFECT LOCAL AIRPORTS DURING THE AFTERNOON. MVFR CEILINGS POSSIBLE IF STORMS MOVE ACROSS AIRPORT. && .BOU WATCHES/WARNINGS/ADVISORIES...NONE. D-L/COOPER
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE DENVER CO 1033 AM MDT SUN JUL 05 2009 COZ030>051-061200- 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- 1033 AM MDT SUN JUL 05 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS...THEN SPREAD ACROSS THE PLAINS DURING THE AFTERNOON AND EVENING. MOST OF THE STORMS WILL BE UNDER SEVERE LIMITS...PRODUCING HEAVY RAIN... SMALL HAIL AND GUSTY WINDS. A FEW STORMS MAY BECOME SEVERE WITH HAIL UP TO ONE INCH IN DIAMETER AND WIND GUSTS TO 60 MPH. THE STORMS WILL END DURING THE EVENING AS AN UPPER LEVEL DISTURBANCE MOVES EAST OF THE AREA. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY MUCH DRIER AND WARMER CONDITIONS ASSOCIATED WITH A STRONG HIGH PRESSURE RIDGE ALOFT WILL SPREAD ACROSS THE REGION THIS WEEK. AS A RESULT...JUST A SLIGHT CHANCE OF THUNDERSTORMS IS EXPECTED EACH AFTERNOON AND EVENING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY OR TONIGHT. HOWEVER... REPORTS OF HEAVY RAINFALL WILL BE APPRECIATED. D-L/COOPER
The Denver radar (KFTG), 36 km away, was scanning. The volume nearest the first event began at 22:28 UTC.
5 thunderstorm wind, 2 hail, 1 tornado. Local standard time, as filed.
A wet microburst produced strong winds and very heavy rain; 1.5 inches in 30 minutes.
Damaging winds from a wet microburst downed two 30-ft flag poles. Several tree branches 3 inches in diameter were snapped, and a wind gage broke.
A tornado touched down briefly but did no damage.
Microburst winds downed a light pole in Sterling, along with several trees. A roof was also torn off an apartment building.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2009Every state in 2009This day in weather historyThe tornado archive for Colorado, 2009Warnings in Colorado, July 2009
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: 174117, 174121, 174120, 174114, 174128, 174118, 174119, 174115.