Alert archive / Colorado / Severe Thunderstorm Warnings in 2008

Severe Thunderstorm Warning 57, NWS Denver/Boulder, CO

June 19, 2008Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 19, 2008, 8:58 PM MDT for Arapahoe County, Colorado. It was in force for 33 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 19, 2008, 8:58 PM MDT (02:58 UTC)
Expired
Jun 19, 2008, 9:31 PM MDT
In force
33 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon

County Arapahoe County, CO

The radar

The Denver radar (KFTG), 18 km from the middle of the area, began a volume at 03:01 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Jun 19, 6:22 PM MDTSevere Thunderstorm WatchSPC27 hr

The nearest sounding before it

Denver, CO (KDNR), launched 00:00Z, 3.0 hours before the alert went out and 125 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-pSkew-T log-p diagram, Denver, CO at 00:00Z on 2008-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 361 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Denver, CO at 00:00Z on 2008-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -38 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
361 J/kg
Mixed-layer CIN
-70 J/kg
Mixed-layer LCL
2794 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
-38 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS55 KBOU 200258
SVRBOU
COC005-200345-
/O.NEW.KBOU.SV.W.0057.080620T0258Z-080620T0345Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
858 PM MDT THU JUN 19 2008

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  WESTERN ARAPAHOE COUNTY IN NORTHEAST COLORADO

* UNTIL 945 PM MDT

* AT 858 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED OVER EXTREME NORTHEASTERN CENTENNIAL...OR 13
  MILES SOUTHEAST OF DENVER...MOVING SOUTHEAST AT 15 MPH.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO BUCKLEY
  AFB...ARAPAHOE PARK...EASTERN CENTENNIAL AND SOUTHERN AURORA.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A STRONG
BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY
LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. STAY INSIDE AWAY
FROM WINDOWS UNTIL THE STORM HAS PASSED.

LAT...LON 3970 10456 3957 10456 3957 10483 3972 10479
TIME...MOT...LOC 0258Z 305DEG 19KT 3961 10471

$$

RPK
3 follow-up statements
000 
WWUS55 KBOU 200307
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
907 PM MDT THU JUN 19 2008

COC005-200345-
/O.CON.KBOU.SV.W.0057.000000T0000Z-080620T0345Z/
ARAPAHOE CO-
907 PM MDT THU JUN 19 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM MDT
FOR WESTERN ARAPAHOE COUNTY...

AT 907 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL.  THIS STORM WAS LOCATED OVER EXTREME NORTHEASTERN CENTENNIAL...
OR 15 MILES SOUTHEAST OF DENVER...MOVING SOUTHEAST AT 15 MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
BUCKLEY AFB...ARAPAHOE PARK...EASTERN CENTENNIAL AND SOUTHERN AURORA.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A STRONG
BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY
LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. STAY INSIDE AWAY
FROM WINDOWS UNTIL THE STORM HAS PASSED.

LAT...LON 3970 10456 3957 10456 3957 10483 3972 10479
TIME...MOT...LOC 0307Z 305DEG 19KT 3960 10469

$$

RPK
000 
WWUS55 KBOU 200322
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
922 PM MDT THU JUN 19 2008

COC005-200345-
/O.CON.KBOU.SV.W.0057.000000T0000Z-080620T0345Z/
ARAPAHOE CO-
922 PM MDT THU JUN 19 2008

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM MDT
FOR WESTERN ARAPAHOE COUNTY...

AT 922 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE HAIL. 
THIS STORM WAS LOCATED 6 MILES SOUTHEAST OF ARAPAHOE PARK...OR 22
MILES SOUTHEAST OF DENVER...MOVING EAST AT 10 MPH.

LOCATIONS REMAINING IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
ARAPAHOE PARK AND SOUTH CENTRAL AURORA.

IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A STRONG
BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...AND DEADLY
LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS. STAY INSIDE AWAY
FROM WINDOWS UNTIL THE STORM HAS PASSED.

LAT...LON 3970 10456 3957 10456 3957 10471 3970 10469
TIME...MOT...LOC 0322Z 305DEG 19KT 3957 10454

$$

RPK
000 
WWUS55 KBOU 200331
SVSBOU

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
931 PM MDT THU JUN 19 2008

COC005-200341-
/O.CAN.KBOU.SV.W.0057.000000T0000Z-080620T0345Z/
ARAPAHOE CO-
931 PM MDT THU JUN 19 2008

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN ARAPAHOE COUNTY IS
CANCELLED...

THE THUNDERSTORM THAT PROMPTED THE WARNING HAS WEAKENED AND IS NO
LONGER EXPECTED TO PRODUCE SEVERE WEATHER.

LAT...LON 3970 10456 3957 10456 3957 10471 3970 10469
TIME...MOT...LOC 0331Z 305DEG 19KT 3954 10449

$$

RPK

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.

Hazardous weather outlook, Jun 19, 11:09 AM MDT, 9 hours 49 minutes before
HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1109 AM MDT THU JUN 19 2008

COZ030>051-201200-
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-
1109 AM MDT THU JUN 19 2008

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

.DAY ONE...TODAY AND TONIGHT

AFTER A FEW EARLY MORNING THUNDERSTORMS...CLEARING SKIES WILL ALLOW
STRONG SOLAR HEATING TO DESTABILIZE THE ATMOSPHERE SUFFICIENTLY TO
PRODUCE AT LEAST ISOLATED THUNDERSTORMS OVER AND NEAR THE FRONT
RANGE AND PALMER DIVIDE AFTER 3 PM TODAY.  NORTHWESTERLY FLOW ALOFT
SHOULD CARRY MOST OF THESE STORMS OVER AREAS MAINLY SOUTH AND WEST
OF DENVER. UPSLOPING NORTHEAST WINDS...PRODUCED BY POWERFUL
THUNDERSTORMS OVER SOUTH DAKOTA AND NEBRASKA LATE LAST NIGHT...WILL
ALSO PROVIDE ADDITIONAL MOISTURE FOR THIS THUNDERSTORM DEVELOPMENT
LATER TODAY.  WHEREAS THIS SAME NORTHEAST FLOW MAY ALSO STABILIZE
THE ATMOSPHERE ON THE PLAINS...THEREBY HINDERING THUNDERSTORM
FORMATION OUT THERE.  WIND GUSTS TO AROUND 45 MPH...LIGHTNING
BRIEF HEAVY RAIN AND SMALL HAIL WILL BE POSSIBLE WITH THE
THUNDERSTORMS OVER AND NEAR THE FRONT RANGE RANGE AND PALMER
DIVIDE.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THERE WILL BE A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS
EACH DAY...MORE NUMEROUS ACROSS THE EASTERN PLAINS. THERE IS THE
POSSIBILITY THAT STORMS THAT DO DEVELOP MAY BE SEVERE ON FRIDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.

BAKER/ENTREKIN

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 8:26 PM MDTSevere Thunderstorm WarningBOULogan49 min
Jun 19, 9:06 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick23 min
Jun 19, 9:43 PM MDTSevere Thunderstorm WarningBOUElbert28 min
Jun 20, 11:37 AM MDTSevere Thunderstorm WarningBOULincoln38 min
Jun 20, 12:08 PM MDTTornado WarningBOULincoln37 min
Jun 20, 1:09 PM MDTSevere Thunderstorm WarningBOUElbert, Lincoln51 min
Jun 20, 3:31 PM MDTSevere Thunderstorm WarningBOUWashington44 min
Jun 20, 5:14 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld46 min
Jun 20, 5:49 PM MDTTornado WarningBOUMorgan26 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2008Every severe thunderstorm warning in 2008

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.