A small tornado touched down. One tree was snapped but no other damage was reported.
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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.
A small tornado touched down. One tree was snapped but no other damage was reported.
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 18, 2:15 AM MST, 10 hours 55 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER CO 315 AM MDT SAT AUG 18 2007 .SHORT TERM...LOOKING LIKE A RATHER NONDESCRIPT SUMMER DAY. NOT A LOT OF CHANGE FROM YESTERDAY...PERHAPS A LITTLE LOW LEVEL DRYING WITH WEAK NORTHERLY SURGE THAT STALLED ACROSS THE SOUTHERN PART OF OUR AREA OVERNIGHT. WHILE THE MOST OBVIOUS FRONTAL BOUNDARY IS ACROSS NORTHERN NEBRASKA AND NORTHEAST WYOMING...THERE IS A SECONDARY BOUNDARY THAT IS NOT WELL DEFINED AT THE SURFACE BUT HAS A RIBBON OF UPWARD QG FORCING ALOFT. THIS HAS BEEN ACTIVE WITH CONVECTION EACH DAY. THIS ZONE HAS SAGGED SOUTH FROM NEBRASKA ACROSS NORTHEASTERN COLORADO TO NORTH OF GRAND JUNCTION. THIS BOUNDARY SHOULD AGAIN LIFT NORTH A BIT DURING THE DAY THEN DROP SOUTH ON THE OUTFLOW AFTER STORMS DEVELOP. HARD TO SAY EXACTLY WHERE THE SHOWERS WILL BE CONCENTRATED...BUT LAST NIGHTS SOUTHWARD MOTION PLUS THE DIURNAL WIND PATTERNS SUGGEST OVER OR SOUTH OF DENVER. WITH THE LITTLE BIT OF DRYING...CAPES WILL BE MODEST AGAIN...MODELS SUGGEST 600-1400 J/KG. NOT MUCH RISK OF ANY KIND OF SEVERE WEATHER...BUT WE SHOULD WIND UP WITH A DECENT CROP OF GARDEN VARIETY THUNDERSTORMS. SECONDARY JET STREAK MOVES FROM UTAH ACROSS WYOMING OVERNIGHT... BRINGING A BIT MORE WESTERLY WIND ALOFT AND DRYING OVERNIGHT. SHOULD BE DECENT CLEARING IN THE MOUNTAINS AFTER MIDNIGHT...NOT AS SURE ABOUT THE PLAINS. OVERALL NOT MUCH TO CHANGE IN THE GOING FORECAST. I DID LOWER HIGHS AND LOWS IN THE MOUNTAINS A COUPLE OF DEGREES AS CLOUD COVER WILL HOLD BACK HIGHS AND CLEARING SHOULD ALLOW SOME COOLING FROM THE LAST COUPLE OF NIGHTS. .LONG TERM...MODELS HAVE THE UPPER RIDGE CENTERED OVER THE SOUTHWESTERN UNITED STATES ON SUNDAY AND SUNDAY NIGHT WITH FAIRLY STRONG WESTERLY FLOW ALOFT OVER THE FORECAST AREA. BY MONDAY A WEAK UPPER TROUGH MOVES ACROSS US WITH NORTHWESTERLY FLOW ALOFT LATER MONDAY AND MONDAY NIGHT. THERE IS SOME WEAK UPWARD VERTICAL VELOCITY LATE SUNDAY AND SUNDAY NORTH FOR THE NORTHERN FORECAST AREA. MONDAY AFTERNOON AND EVENING THERE IS WEAK DOWNWARD MOTION PROGGED. THE BOUNDARY LAYER WIND PROGGS SHOW SOME DOWNSLOPING AFTER THE UPPER TROUGH MOVES OVER LATER MONDAY INTO TUESDAY. FOR MOISTURE...THERE IS SOME IN MAINLY IN THE MID AND UPPER LEVELS ON SUNDAY...WITH A BIT LESS FOR MONDAY. THE NAM BOUNDARY LAYER DEW POINTS ARE MAINLY IN THE 40S ON SUNDAY...WITH UPPER 30S F TO UPPER 40S ON MONDAY. PRECIPITABLE WATER VALUES ON THE FORECAST SOUNDINGS HAVE 0.70 TO 0.90 INCH THROUGH MONDAY NIGHT. THE THETA-E AXIS IS MAINLY SOUTHWEST AND EAST OF THE FORECAST AREA THROUGH THE PERIOD. THE CAPE IS FAIRLY SPARSE BOTH AFTERNOONS...WITH MONDAYS A TAD BETTER. THE QPF GRIDS SHOW VERY LITTLE RAINFALL EITHER DAY. WILL CHANCE LITTLE TO THE ALREADY MINIMAL POPS. FOR TEMPERATURES... SUNDAY IS 1-2 C WARMER THAN TODAY. MONDAY IS SIMILAR TO A TAD WARMER. WILL CHANGE NOTHING OF THE LATER DAYS...TUESDAY THROUGH FRIDAY. .AVIATION...ISOLATED THUNDERSTORMS ARE EXPECTED TO DEVELOP AFTER 20Z...ENDING BY 06Z. THE STORMS WILL BE MORE NUMEROUS OVER THE MOUNTAINS. A FEW OF THE STORMS COULD PRODUCE LOCALIZED MVFR VISIBILITIES AND WIND GUSTS TO 30 KNOTS. && .BOU WATCHES/WARNINGS/ADVISORIES...NONE. && GIMMESTAD/RJK
HAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE DENVER CO 1130 AM MDT SAT AUG 18 2007 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- 1130 AM MDT SAT AUG 18 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT HEAT GENERATED THUNDERSTORMS WILL BEGIN FORMING OVER THE MOUNTAINS AND HIGH VALLEYS WEST OF THE CONTINENTAL DIVIDE BY AROUND MIDDAY...AND BECOME SCATTERED IN COVERAGE BY AROUND 2 PM. EXPECT GUSTY WINDS...DEADLY LIGHTNING AND BRIEF HEAVY RAIN WITH THESE EASTWARD MOVING STORMS. THEN LOOK FOR WIDELY SCATTERED THUNDERSTORMS TO DRIFT OFF THE FOOTHILLS AND OVER THE NEARBY HIGH PLAINS BETWEEN 2 AND 4 PM. EXPECT THESE STORMS TO PRODUCE GUSTY WINDS...DEADLY LIGHTNING AND BRIEF LIGHT TO MODERATE RAINFALL. EAST OF THE INTERSTATE I-25 CORRIDOR...A DRIER AND MORE STABLE ATMOSPHERE WILL HINDER THUNDERSTORM DEVELOPMENT...AND THEREFORE ONLY ISOLATED WEAK STORMS ARE EXPECTED TO DRIFT EAST ACROSS THE NORTHEAST PLAINS. THUNDERSTORMS SHOULD DISSIPATE BY AROUND 8 PM. ALTHOUGH A FEW STORMS IN LINCOLN COUNTY AND NEAR THE NORTHEAST CORNER OF THE STATE MAY LINGER UNTIL AROUND MIDNIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY VERY WARM AND MOSTLY DRY CONDITIONS ARE EXPECTED TO PREVAIL THROUGH THE FIRST HALF OF THE WEEK...EXCEPT FOR A SLIGHT CHANCE OF THUNDERSTORMS OVER THE MOUNTAINS AND FOOTHILLS SUNDAY AFTERNOON. HIGH TEMPERATURES ON THE PLAINS MONDAY AND TUESDAY ARE EXPECTED TO BE WELL INTO THE 90S. COOLER TEMPERATURES ARE EXPECTED FOR THE LATTER HALF OF THE WEEK...ALONG WITH A RETURN OF ISOLATED AFTERNOON AND EVENING THUNDERSTORMS EACH DAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT. BAKER/DANKERS
The Denver radar (KFTG), 89 km away, was scanning. The volume nearest the first event began at 20:09 UTC.
1 tornado. Local standard time, as filed.
A small tornado touched down. It snapped one tree.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2007Every state in 2007This day in weather historyThe tornado archive for Colorado, 2007Warnings in Colorado, August 2007
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: 61214.