Alert archive / Colorado / Tornado Watches in 2003

Tornado Watch 550

June 20, 200324 counties in Colorado

The Storm Prediction Center issued this tornado watch at Jun 20, 2003, 12:45 PM MDT for 24 counties in Colorado. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Jun 20, 2003, 12:45 PM MDT (18:45 UTC)
Expired
Jun 20, 2003, 8:00 PM MDT
In force
7 hr
Issued by
the Storm Prediction Center
All 24 counties

Adams County, CO, Arapahoe County, CO, Baca County, CO, Bent County, CO, Cheyenne County, CO, Crowley County, CO, Denver County, CO, Douglas County, CO, El Paso County, CO, Elbert County, CO, Kiowa County, CO, Kit Carson County, CO, Las Animas County, CO, Lincoln County, CO, Logan County, CO, Morgan County, CO, Otero County, CO, Phillips County, CO, Prowers County, CO, Pueblo County, CO, Sedgwick County, CO, Washington County, CO, Weld County, CO, Yuma County, CO

The radar

The Denver radar (KFTG), 119 km from the middle of the area, began a volume at 18:47 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.

Warnings issued inside it

14 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jun 20, 2:06 PM MDTSevere Thunderstorm WarningPUBEl Paso, Pueblo54 min
Jun 20, 3:05 PM MDTSevere Thunderstorm WarningBOUMorgan40 min
Jun 20, 3:17 PM MDTSevere Thunderstorm WarningBOUAdams43 min
Jun 20, 3:48 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan57 min
Jun 20, 3:53 PM MDTSevere Thunderstorm WarningPUBKiowa52 min
Jun 20, 4:19 PM MDTSevere Thunderstorm WarningGLDCheyenne56 min
Jun 20, 4:41 PM MDTSevere Thunderstorm WarningBOUMorgan64 min
Jun 20, 5:06 PM MDTSevere Thunderstorm WarningBOUWashington54 min
Jun 20, 5:51 PM MDTSevere Thunderstorm WarningGLDYuma54 min
Jun 20, 5:53 PM MDTTornado WarningBOULogan52 min
Jun 20, 6:00 PM MDTSevere Thunderstorm WarningBOUWashington30 min
Jun 20, 6:01 PM MDTSevere Thunderstorm WarningBOUWashington29 min
Jun 20, 6:02 PM MDTSevere Thunderstorm WarningGLDKit Carson58 min
Jun 20, 6:45 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick60 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 6.8 hours before the alert went out and 55 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 12:00Z on 2003-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2003-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1432 m above ground
0-6 km bulk shear
9 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
-35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
WWUS20 KWNS 201847
SEL0  
SPC WW 201845
COZ000-210200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 550 
NWS STORM PREDICTION CENTER NORMAN OK 
1245 PM MDT FRI JUN 20 2003

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF 

       EASTERN COLORADO

EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 1245 PM UNTIL 800
PM MDT.

TORNADOES...HAIL TO 3 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 75 STATUTE MILES EAST AND WEST
OF A LINE FROM 60 MILES NORTH NORTHWEST OF AKRON COLORADO TO 55
MILES EAST SOUTHEAST OF TRINIDAD COLORADO.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.


OTHER WATCH INFORMATION...CONTINUE...WW 547...WW 548...WW 549...


DISCUSSION...SCATTERED THUNDERSTORMS/SUPERCELLS EXPECTED OVER WW
AREA THIS AFTERNOON AND EVENING...WHERE DEEP DIRECTIONAL/SPEED SHEAR
WILL INCREASE DOWNSTREAM FROM EJECTING/INCREASINGLY
NEGATIVELY-TILTED SRN STREAM IMPULSE CROSSING 4 CORNERS REGION. 
FAIRLY RICH BOUNDARY LAYER MOISTURE AVAILABILITY AND LIKELY
SUSTAINED NATURE OF SUPERCELLS SUGGEST SOME THREAT FOR TORNADOES
DESPITE LIMITED LOW LEVEL DIRECTIONAL SHEAR.

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 3 INCHES. EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550.
MEAN STORM MOTION VECTOR 24025.


...CORFIDI

405,1021 365,1020 365,1044 405,1050

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 20, 12:17 PM MDTMesoscale DiscussionSPCGarfield, Mesa, Moffat, Montrose, Rio Blanco, San Miguel118 min
Jun 20, 2:53 PM MDTMesoscale DiscussionSPCAdams, Arapahoe, Bent, Cheyenne, Crowley, Elbert and 8 more97 min

Nearby

Tornado Watches in Colorado, 2003Every tornado watch in 2003

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.