Colorado, 2009

Tornado and Hail in Colorado, June 9, 2009

June 9, 2009 · NWS BOU · 10 events in 4 counties and zones

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.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
10

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.

What happened

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.

What forecasters said that day

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, Jun 9, 2:00 PM MST, 2 hours 10 minutes before
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, Jun 9, 9:42 AM MST, 6 hours 28 minutes before
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 radar

The Denver radar (KFTG), 78 km away, was scanning. The volume nearest the first event began at 23:09 UTC.

Open the radar archive at this moment

Event by event

8 hail, 1 tornado, 1 heavy rain. Local standard time, as filed.

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

Tornado, Weld

When
June 9, 4:11 PM MST
Where
Weld County, 2.1 mi SE of Liberty
Rating
EF0
Path length
0.1 mi
Path width
50 yd
Reported by
Law Enforcement
Coordinates
40.160, -104.990

A tornado touched down but did no damage.

Hail, Weld

When
June 9, 4:23 PM MST
Where
Weld County, 1.26 mi WSW of Johnstown
Measured
1 in hail
Reported by
Trained Spotter
Coordinates
40.320, -104.870

Heavy Rain, Weld

When
June 9, 4:23 PM MST to 4:59 PM MST
Where
Weld County, Greeley to Johnstown
Reported by
Newspaper
Coordinates
40.420, -104.680

Hail, Weld

When
June 9, 4:28 PM MST
Where
Weld County, 4.44 mi SSE of Bruce
Measured
0.75 in hail
Reported by
Trained Spotter
Coordinates
40.420, -104.820

Hail, Weld

When
June 9, 4:30 PM MST
Where
Weld County, 4.91 mi SSE of Bruce
Measured
0.75 in hail
Reported by
Trained Spotter
Coordinates
40.420, -104.800

Hail, Weld

When
June 9, 4:32 PM MST
Where
Weld County, 0.69 mi S of Johnstown
Measured
1 in hail
Reported by
Amateur Radio
Coordinates
40.320, -104.850

Hail, Washington

When
June 9, 4:53 PM MST
Where
Washington County, 0.87 mi SW of Akron
Measured
0.75 in hail
Reported by
Trained Spotter
Coordinates
40.160, -103.210

Hail, Weld

When
June 9, 4:59 PM MST
Where
Weld County, 3.44 mi WNW of Greeley
Measured
1 in hail
Reported by
Trained Spotter
Coordinates
40.440, -104.740

Hail, Lincoln

When
June 9, 10:10 PM MST
Where
Lincoln County, Arriba
Measured
1 in hail
Reported by
Trained Spotter
Coordinates
39.280, -103.270

What these are

Hail
Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Tornado
A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
Heavy Rain
Rainfall totals unusual for the place and season that did not produce a flood.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Colorado in 2009Every state in 2009This day in weather historyThe tornado archive for Colorado, 2009Warnings in Colorado, June 2009

Sources

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.