Hail, Boulder
- When
- June 9, 4:10 PM MST
- Where
- Boulder County, Lyons
- Measured
- 0.75 in hail
- Reported by
- Trained Spotter
- Coordinates
- 40.220, -105.270
Severe thunderstorms produced heavy rain, large hail and one weak tornado in Weld County. The storm dumped 1 to 2 inches of rain in the Greeley, Evans, Johnstown and Milliken in about 30 minutes causing some street flooding.
Every event with a place to put it. 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.
Severe thunderstorms produced heavy rain, large hail and one weak tornado in Weld County. The storm dumped 1 to 2 inches of rain in the Greeley, Evans, Johnstown and Milliken in about 30 minutes causing some street flooding. Large hail, up to quarter size, was reported in Washington, Weld and Lincoln Counties.
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 Jun 9, 2:00 PM MST, 2 hours 10 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER CO 300 PM MDT TUE JUN 9 2009 .SHORT TERM...WEATHER SITUATION STILL NOT TOTALLY CLEAR AS OF THIS AFTERNOON FOR TONIGHT. THE WEAK SHORT WAVE BEING EJECTED INTO WESTERN COLORADO IS STILL COMING THIS WAY. HEATING TODAY HAS BEEN SLIGHTLY HINDERED BY STRATUS AND FOG EARLIER THIS MORNING. DRIER DEWPOINTS ARE BEING ADVECTED IN FROM THE SOUTHWEST. THE CAP EVIDENT ON THIS MORNINGS SOUNDING STILL HOLDS OVER THE FRONT RANGE PROHIBITING CONVECTIVE INITIATION...HOWEVER HAS WEAKENED OVER THE PALMER RIDGE WHERE A FEW WEAK SHOWERS HAVE FORMED. CAPES OF 1000 TO 1500 ARE OVER THE PLAINS HOWEVER THE CAP AND ASSOCIATED CONVECTIVE INHIBITION VALUES ARE NOT ALLOWING THE CAPES TO BE USED. A LINE OF SHOWERS AND THUNDERSTORMS OVER SOUTHERN WYOMING WILL HELP DESTABILIZE THE AIRMASS ALONG OUR NORTHERN BORDER BY WEAKENING THE CAP WITH OUTFLOWS. HAVE INCREASED THE FORECAST COVERAGE TO NUMEROUS THUNDERSTORMS IN THIS AREA. HAVE KEPT IN SCATTERED TO LIKELY POPS IN THE FORECAST TONIGHT AS WE STILL EXPECT LIFT AHEAD OF THE SHORT WAVE TO HELP CONVECTION LAST LONGER INTO THE EVENING/NIGHT AS THE WAVE PASSES OVER THE STATE TONIGHT. THE WAVE IS EXPECTED TO BE OVER THE STATE RIGHT AROUND MIDNIGHT SO HAVE KEPT SOME SORT OF POPS FORECAST-AREA WIDE THROUGH 3 AM...ESPECIALLY ACROSS THE NORTHEAST CORNER WHERE CONVECTION MAY LAST PAST MIDNIGHT. STILL HAVE A SLIGHT CHANCE FOR A FEW STORMS TO BECOME SEVERE...BRINGING LARGE HAIL AND DAMAGING WINDS. DOWNWARD MOTION ON THE BACKSIDE OF THE WAVE WILL DIMINISH SHOWERS EARLY TOMORROW MORNING AND ALLOW SOME PATCHY FOG TO DEVELOP OVER THE PLAINS. A COLD FRONT CURRENTLY OVER SOUTHERN WYOMING IS ALSO EXPECTED TO DROP DOWN EARLY TOMORROW MORNING. A SURFACE TROUGH ORIENTED NW-SE OVER CENTRAL CO COULD HELP SET UP A DENVER CYCLONE PATTERN. THE COLD FRONT AND THE SURFACE WIND PATTERN WILL HELP FOCUS PRECIPITATION ALONG THE FRONT RANGE AND PALMER DIVIDE...HOWEVER EXPECT LIGHTER AMOUNTS OVER THE REST OF THE FORECAST AREA. TEMPERATURES WILL BE COOLER TOMORROW...ONLY IN THE MID 60S OVER THE PLAINS. AN UPPER DISTURBANCE WILL PASS OVER THE STATE DURING THE DAY TOMORROW BRINGING THE BEST MID LEVEL QG ASCENT IN THE AFTERNOON. THIS WILL HELP INCREASE THE PRECIPITATION AMOUNTS...MAINLY AFTER NOON. BELIEVE THE AIRMASS BEHIND THE COLD FRONT WILL BE QUITE STABLE AND HAVE DECREASED THE THUNDERSTORM COVERAGE TO JUST A SLIGHT CHANCE. .LONG TERM...UPPER LEVEL DISTURBANCE WILL MOVE EAST OF THE AREA WEDNESDAY EVENING...TAKING A WELL ORGANIZED AREA OF SHOWERS AND STORMS WITH IT. BEHIND THIS FEATURE...ATMOSPHERE WILL STABILIZE AND GRADUALLY DRY...BUT STILL CANT RULE OUT A FEW SHOWERS LINGERING PAST MIDNIGHT. IN ADDITION...EXPECT ANOTHER BOUT OF STRATUS AND FOG WEDNESDAY NIGHT INTO THURSDAY MORNING WITH MOIST LOW LEVEL NORTH/ NORTHEAST FLOW IN ITS WAKE. ON THURSDAY...THERE IS YET ANOTHER SHORT WAVE ADVERTISED TO MOVE ACROSS THE AREA. THIS FEATURE CAN BE SEEN RIGHT NOW IN THE WATER VAPOR LOOP OVER THE EASTERN PACIFIC NEAR 40N/140W...SO HAVE INCREASED POPS A BIT MORE FOR THURSDAY. AFTER THAT...AFTERNOON AND EVENING STORM COVERAGE SHOULD DECREASE A BIT AS FLAT UPPER LEVEL RIDGING OCCURS OVER THE CENTRAL AND SOUTHERN ROCKIES. HOWEVER...PLENTY OF LOW LEVEL MOISTURE OVER THE PLAINS AND RELATIVELY STRONG SHEAR WILL STILL KEEP A THREAT OF A FEW SEVERE STORMS IN THE FORECAST THROUGH EARLY NEXT WEEK. TEMPERATURES ARE EXPECTED TO WARM TO NORMAL OR SLIGHTLY ABOVE NORMAL LEVELS FOR THE THE WEEKEND THROUGH EARLY NEXT WEEK. && .AVIATION...EXPECT SCATTERED THUNDERSTORMS WILL FORM THIS LATER AFTERNOON AS THE AIRMASS BECOMES UNSTABLE. THE BEST TIME WILL BE 22-02Z. THE MAIN THREATS WILL BE GUSTY OUTFLOW WINDS TO 30 KNOTS AND SMALL HAIL. ISOLATED SHOWERS WILL LAST THROUGH 06Z. OTHERWISE...EXPECTING LIGHT WINDS...TURNING NORTHERLY PAST 00Z AS A WEAK FRONTAL BOUNDARY PASSES. SHOULD BECOME DRAINAGE PAST 03Z WITH SOME PATCHY FOG FORMING. EXPECT MVFR CEILINGS WITH WIDESPREAD RAIN SHOWERS PAST 18Z. && .BOU WATCHES/WARNINGS/ADVISORIES...NONE. KRIEDERMAN/BARJENBRUCH
HAZARDOUS WEATHER OUTLOOK...CORRECTED NATIONAL WEATHER SERVICE DENVER CO 1042 AM MDT TUE JUN 09 2009 COZ030>051-101200- 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- 1042 AM MDT TUE JUN 09 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL COLORADO. .DAY ONE...TODAY AND TONIGHT SCATTERED THUNDERSTORMS WILL AGAIN DEVELOP THIS AFTERNOON AND EVENING. THE MAIN THREATS WITH THE THUNDERSTORMS WILL BE HEAVY RAIN AND SMALL HAIL. A FEW THUNDERSTORMS COULD BECOME SEVERE WITH LARGE HAIL AND DAMAGING WINDS LATE THIS AFTERNOON AND EVENING. AN UPPER DISTURBANCE MOVING OVER THE STATE THIS EVENING COULD PROLONG THE CONVECTIVE ACTIVITY THROUGH THE EVENING. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY A MOIST AND UNSETTLED WEATHER PATTERN WILL REMAIN IN PLACE THROUGH THE PERIOD WITH AFTERNOON AND EVENING THUNDERSTORMS EACH DAY. THERE WILL BE A THREAT OF A FEW SEVERE STORMS EACH DAY AS WELL GIVEN SUFFICIENT INSTABILITY AND WIND SHEAR IN THE ATMOSPHERE. AT THIS TIME...THE BEST CHANCE OF PRECIPITATION APPEARS TO BE SHAPING UP FOR WEDNESDAY AND WEDNESDAY NIGHT WHEN AN UPPER LEVEL DISTURBANCE IS EXPECTED TO MOVE ACROSS THE STATE. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE REQUIRED ACROSS THE NORTHEAST PLAINS AFTER 2 PM. KRIEDERMAN/BARJENBRUCH
The Denver radar (KFTG), 78 km away, was scanning. The volume nearest the first event began at 23:09 UTC.
8 hail, 1 tornado, 1 heavy rain. Local standard time, as filed.
A tornado touched down but did no damage.
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, June 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: 165592, 165600, 165594, 176265, 165591, 165595, 165596, 165597, 165598, 165599.