Alert archive / Colorado / Severe Thunderstorm Warnings in 2010

Severe Thunderstorm Warning 71, NWS Denver/Boulder, CO

June 11, 2010Clear Creek County, Jefferson County, Park County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 11, 2010, 2:43 PM MDT for Clear Creek County, Jefferson County, Park County, Colorado. It was in force for 32 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 11, 2010, 2:43 PM MDT (20:43 UTC)
Expired: Jun 11, 2010, 3:15 PM MDT
In force: 32 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.25 in
Wind: 50.0 mph

Counties Clear Creek County, CO, Jefferson County, CO, Park County, CO

The radar

The Denver radar (KFTG), 92 km from the middle of the area, began a volume at 20:44 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 8.7 hours before the alert went out and 203 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1293 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: -56 m²/s²
0-3 km storm-relative helicity: 44 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.6

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Jun 11, 4:30 AM MDT, 10 hours 13 minutes earlier.

Area forecast discussion, Jun 11, 4:30 AM MDT, 10 hours 13 minutes before

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Hazardous weather outlook, Jun 11, 11:00 AM MDT, 3 hours 43 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1100 AM MDT FRI JUN 11 2010

COZ030>051-121200-
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-
1100 AM MDT FRI JUN 11 2010

...FLOOD WATCH FOR PORTIONS OF LARIMER...WELD...AND BOULDER COUNTIES
TONIGHT THROUGH SATURDAY NIGHT...

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

.DAY ONE...TODAY AND TONIGHT

A VERY MOIST AIRMASS COUPLED WITH A DEEPENING UPPER LEVEL LOW OVER
THE SOUTHWEST WILL BRING WIDESPREAD THUNDERSTORMS AND SOME HEAVY
RAINS TO THE AREA THROUGH TONIGHT.  UPSLOPE FLOW IS DEEPENING OVER
THE AREA AND SHOWERS AND THUNDERSTORMS WILL SOON BE DEVELOPING IN
THE FOOTHILLS.  THESE WILL INCREASE IN COVERAGE LATER THIS AFTERNOON
AND TONIGHT WITH THE FOCUS FOR THE HEAVIEST RAINS IN AND NEAR THE
FOOTHILLS FROM WEST OF DENVER NORTH TO THE WYOMING BORDER.  GENERAL
RAINFALL TOTALS OF ONE TO TWO INCHES ARE POSSIBLE...WITH LOCALLY
MORE...ESPECIALLY IN LARIMER COUNTY.  A FLOOD WATCH REMAINS IN
EFFECT FOR MUCH OF THIS AREA THROUGH SATURDAY NIGHT.

AS THE PRECIPITATION BECOMES MORE WIDESPREAD TONIGHT THE SNOW LEVEL
WILL LOWER FROM AROUND 10000 FEET TO AROUND 9000 FEET BY SATURDAY
MORNING.  SEVERAL INCHES OF SNOW ARE LIKELY AT HIGHER ELEVATIONS
WHICH COULD CLOSE SEASONAL ROADS SUCH AS TRAIL RIDGE ROAD IN ROCKY
MOUNTAIN NATIONAL PARK.

ON THE PLAINS THE ATMOSPHERE IS NOT AS UNSTABLE AS YESTERDAY BUT
WITH ALL THE MOISTURE IN PLACE AND AFTERNOON HEATING SOME
THUNDERSTORMS COULD BECOME SEVERE.  AT THIS TIME LARGE HAIL APPEARS
TO BE THE MAIN THREAT WITH STRONG STORMS PERSISTING INTO THIS
EVENING.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A COOL AND WET WEATHER PATTERN WILL REMAIN OVER NORTH CENTRAL AND
NORTHEAST COLORADO THROUGH THE WEEKEND. PERIODS OF RAIN ARE EXPECTED
THROUGH SUNDAY AFTERNOON WITH SNOW ABOVE 10000 FEET AND POSSIBLY
MIXED DOWN TO 9000 FEET. SNOW ACCUMULATIONS OF 3 TO 6 INCHES ARE
POSSIBLE ABOVE 10000 FEET...MAINLY EAST OF THE CONTINENTAL DIVIDE.
MODERATE TO HEAVY RAIN MAY CAUSE STREAMS AND RIVERS TO RISE THE
WEEKEND ALONG THE FRONT RANGE...POSSIBLY FLOODING LOW LYING AREAS.

FOR NEXT WEEK THERE WILL BE A SLIGHT CHANCE FOR AFTERNOON AND
EVENING SHOWERS AND THUNDERSTORMS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 1 PM.

SZOKE/MEIER

In the hours before

Local storm report, Jun 11, 9:31 AM MDT, 5 hours 12 minutes before

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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 10, 6:11 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Broomfield, Jefferson, Weld	49 min
Jun 10, 6:11 PM MDT	Tornado Warning	BOU	Weld	34 min
Jun 10, 6:29 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	61 min
Jun 10, 6:37 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	38 min
Jun 10, 6:41 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	64 min
Jun 10, 6:51 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Weld	54 min
Jun 10, 7:09 PM MDT	Tornado Warning	BOU	Arapahoe, Washington	51 min
Jun 10, 7:21 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Morgan, Washington	84 min
Jun 10, 7:43 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Weld	46 min
Jun 10, 7:45 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Morgan, Washington	60 min
Jun 10, 7:48 PM MDT	Tornado Warning	BOU	Washington	42 min
Jun 10, 8:05 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Morgan, Weld	55 min
Jun 10, 8:12 PM MDT	Tornado Warning	BOU	Washington	48 min
Jun 10, 8:54 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Morgan, Washington	66 min
Jun 10, 8:57 PM MDT	Tornado Warning	BOU	Washington	48 min
Jun 10, 10:00 PM MDT	Severe Thunderstorm Warning	BOU	Washington	60 min
Jun 10, 10:25 PM MDT	Severe Thunderstorm Warning	BOU	Phillips, Sedgwick	19 min
Jun 10, 10:54 PM MDT	Severe Thunderstorm Warning	BOU	Washington	36 min
Jun 11, 3:14 PM MDT	Severe Thunderstorm Warning	BOU	Denver, Jefferson	31 min
Jun 11, 3:26 PM MDT	Areal Flood Advisory	BOU	Jefferson	79 min
Jun 11, 3:44 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Denver, Jefferson	31 min
Jun 11, 3:51 PM MDT	Tornado Warning	BOU	Adams, Broomfield, Denver, Jefferson, Weld	39 min
Jun 11, 3:58 PM MDT	Areal Flood Advisory	BOU	Adams	67 min
Jun 11, 4:02 PM MDT	Severe Thunderstorm Warning	BOU	Weld	58 min
Jun 11, 4:18 PM MDT	Areal Flood Advisory	BOU	Weld	87 min
Jun 11, 4:22 PM MDT	Tornado Warning	BOU	Adams, Denver, Weld	38 min
Jun 11, 4:35 PM MDT	Tornado Warning	BOU	Elbert	40 min
Jun 11, 4:42 PM MDT	Tornado Warning	BOU	Weld	48 min
Jun 11, 4:55 PM MDT	Tornado Warning	BOU	Elbert	50 min
Jun 11, 4:59 PM MDT	Tornado Warning	BOU	Adams, Morgan, Weld	46 min
Jun 11, 5:00 PM MDT	Areal Flood Advisory	BOU	Elbert	90 min
Jun 11, 5:14 PM MDT	Areal Flood Advisory	BOU	Morgan, Weld	54 min
Jun 11, 5:28 PM MDT	Tornado Warning	BOU	Weld	47 min
Jun 11, 5:32 PM MDT	Flash Flood Warning	BOU	Morgan, Weld	3 hr
Jun 11, 5:37 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	53 min
Jun 11, 5:40 PM MDT	Tornado Warning	BOU	Morgan, Weld	35 min
Jun 11, 5:46 PM MDT	Tornado Warning	BOU	Elbert, Lincoln	44 min
Jun 11, 5:49 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver	86 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2010 Every severe thunderstorm warning in 2010

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.