Alert archive / Colorado / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 61, NWS Denver/Boulder, CO

June 15, 1997Adams County, Boulder County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 15, 1997, 3:11 PM MDT for Adams County, Boulder County, Weld County, Colorado. It was in force for 34 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued
Jun 15, 1997, 3:11 PM MDT (21:11 UTC)
Expired
Jun 15, 1997, 3:45 PM MDT
In force
34 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

Counties Adams County, CO, Boulder County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 35 km from the middle of the area, began a volume at 21:11 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.

What was reported inside it

TimeReportWhereRemark
Jun 15, 3:21 PM MDTTornado F1Dacono, COA tornado touched down briefly at the Colorado National Speedway. The tornado ripped through the south grandstand causing at least $50, 000 in damage to a shed, kiosk, bleachers and several concession stands.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 9.2 hours before the alert went out and 126 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 1997-06-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 62 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 12:00Z on 1997-06-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -73 square meters per square second.1939587897Sfc1 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
62 J/kg
Mixed-layer CIN
-239 J/kg
Mixed-layer LCL
1525 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-73 m²/s²
0-3 km storm-relative helicity
-77 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 
TTAA00 KDEN 152115 RRA
SVRDEN
COC001-013-123-152145-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
311 PM MDT SUN JUN 15 1997

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 345 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...

IN NORTHEAST COLORADO
     SOUTHEASTERN BOULDER...NORTHWESTERN ADAMS AND SOUTHWESTERN WELD

INCLUDING THE FOLLOWING LOCATIONS
     LONGMONT...BRIGHTON...DACONO...ERIE...FIRESTONE...FORT 
     LUPTON...FREDERICK...HUDSON...KEENESBURG...LAFAYETTE...
     LOCHBUIE...MILTON RESERVOIR...PLATTEVILLE AND PROSPECT VALLEY

AT 305 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 6 MILES NORTH OF HUDSON...OR ABOUT 20 MILES SOUTH
OF GREELEY.

THE STORM WAS STATIONARY.

PUBLIC REPORTS OF SEVERAL FUNNEL CLOUDS WERE ASSOCIATED WITH ANOTHER 
DEVELOPING STORM OVER ERIE.
 
IF SEVERE WEATHER APPROACHES YOUR AREA...GO INSIDE A STURDY SHELTER
AWAY FROM CREEK BEDS AND OTHER FLOOD-PRONE AREAS. REMEMBER...A SEVERE
THUNDERSTORM CAN PRODUCE LARGE DAMAGING HAIL...DAMAGING WINDS OVER 60
MPH...DEADLY LIGHTNING...AND VERY HEAVY RAIN.

THESE THUNDERSTORMS COULD PRODUCE ADDITIONAL BRIEF FUNNEL CLOUDS OR 
SHORT-LIVED TORNADOES WITH LITTLE OR NO ADVANCE WARNING.  PREPARE TO 
MOVE TO A PLACE OF SAFETY IN A STURDY STRUCTURE SUCH AS A BASEMENT 
OR SMALL INTERIOR ROOM IF A TORNADO IS SPOTTED.

HEAVY RAINS FROM THESE STORMS MAY FLOOD LOW LYING AREAS SUCH AS 
DITCHES AND UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED 
ROADS AS THEY MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND 
RIVERS MAY ALSO RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY 
FLOOD WATERS.

REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY
WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST
OFFICE IN DENVER.

DANKERS
LAT...LON 4001 10437 3994 10511 4014 10516 4032 10441

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.

In the hours before

Special weather statement, Jun 15, 11:25 AM MDT, 3 hours 46 minutes before
COZ030-032>050-160600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1125 AM MDT SUN JUN 15 1997

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

SYNOPSIS: THE AIRMASS OVER NORTHEAST COLORADO HAS MODIFIED THIS
MORNING IN THE WAKE OF A WEATHER DISTURBANCE WHICH PASSED SOUTH OF
THE AREA OVERNIGHT.  AS A RESULT...THE CURRENT WIND PROFILE DOES NOT
FAVOR THE DEVELOPMENT OF STRONG OR EVEN SEVERE THUNDERSTORMS TODAY.

THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THE FOOTHILLS...MOVING
ONTO THE PLAINS DURING THE AFTERNOON AND EVENING.  A WEAK COLD FRONT
AN AND UPPER LEVEL DISTURBANCE WILL MOVE ACROSS NORTHEAST COLORADO
THIS AFTERNOON...BRINGING AN INCREASE IN LOW LEVEL MOISTURE ACROSS
NORTHEAST COLORADO.  AS A RESULT...SOME OF THE STORMS COULD PRODUCE
BRIEF HEAVY RAINS AS WELL AS SMALL HAIL...MAINLY EAST OF A LIMON TO
AKRON LINE AND OVER THE MOUNTAINS AND HIGHER FOOTHILLS.

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY.

LESZCYNSKI
Special weather statement, Jun 15, 11:26 AM MDT, 3 hours 45 minutes before
COZ030-032>050-160600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1125 AM MDT SUN JUN 15 1997

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

SYNOPSIS: THE AIRMASS OVER NORTHEAST COLORADO HAS MODIFIED THIS
MORNING IN THE WAKE OF A WEATHER DISTURBANCE WHICH PASSED SOUTH OF
THE AREA OVERNIGHT.  AS A RESULT...THE CURRENT WIND PROFILE DOES NOT
FAVOR THE DEVELOPMENT OF STRONG OR EVEN SEVERE THUNDERSTORMS TODAY.

THUNDERSTORMS WILL CONTINUE TO DEVELOP ALONG THE FOOTHILLS...MOVING
ONTO THE PLAINS DURING THE AFTERNOON AND EVENING.  A WEAK COLD FRONT
AN AND UPPER LEVEL DISTURBANCE WILL MOVE ACROSS NORTHEAST COLORADO
THIS AFTERNOON...BRINGING AN INCREASE IN LOW LEVEL MOISTURE ACROSS
NORTHEAST COLORADO.  AS A RESULT...SOME OF THE STORMS COULD PRODUCE
BRIEF HEAVY RAINS AS WELL AS SMALL HAIL...MAINLY EAST OF A LIMON TO
AKRON LINE AND OVER THE MOUNTAINS AND HIGHER FOOTHILLS.

SPOTTER ACTIVATION IS NOT ANTICIPATED TODAY.

LESZCYNSKI
Special weather statement, Jun 15, 2:25 PM MDT, 46 minutes before
COZ041-046-047-152100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
225 PM MDT SUN JUN 15 1997

...STRONG THUNDERSTORM WINDS AND HAIL POSSIBLE IN ELBERT COUNTY...

AT 220 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF THUNDERSTORMS OVER CENTRAL AND SOUTHEAST ELBERT COUNTY.  THE
STRONGEST STORM WAS LOCATED 3 MILES NORTHWEST OF KUTCH...OR ABOUT 27
MILES SOUTHWEST OF LIMON.

THESE STORMS WERE MOVING SLOWLY TO THE SOUTHEAST AT 5 MILES PER HOUR.

PERSONS IN OR NEAR ELIZABETH...KIOWA...KUTCH...MATHESON AND SIMLA
SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER..SUCH AS WIND GUSTS
TO 50 MPH...HAIL AND DANGEROUS LIGHTNING.  IF SEVERE WEATHER SHOULD
DEVELOP...MOVE QUICKLY TO A PLACE OF SAFETY.

BAKER...WSFO DENVER
Special weather statement, Jun 15, 2:26 PM MDT, 45 minutes before
COZ041-046-047-152100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
225 PM MDT SUN JUN 15 1997

...STRONG THUNDERSTORM WINDS AND HAIL POSSIBLE IN ELBERT COUNTY...

AT 220 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
LINE OF THUNDERSTORMS OVER CENTRAL AND SOUTHEAST ELBERT COUNTY.  THE
STRONGEST STORM WAS LOCATED 3 MILES NORTHWEST OF KUTCH...OR ABOUT 27
MILES SOUTHWEST OF LIMON.

THESE STORMS WERE MOVING SLOWLY TO THE SOUTHEAST AT 5 MILES PER HOUR.

PERSONS IN OR NEAR ELIZABETH...KIOWA...KUTCH...MATHESON AND SIMLA
SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER..SUCH AS WIND GUSTS
TO 50 MPH...HAIL AND DANGEROUS LIGHTNING.  IF SEVERE WEATHER SHOULD
DEVELO6P...MOVE QUICKLY TO A PLACE OF SAFETY.

BAKER...WSFO DENVER
Special weather statement, Jun 15, 2:30 PM MDT, 41 minutes before
COZ030-032>050-160600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
230 PM MDT SUN JUN 15 1997

THIS UPDATED OUTLOOK PERTAINS TO THE FOLLOWING COLORADO COUNTIES

ADAMS     ARAPAHOE     BOULDER   CLEAR CREEK   DENVER       DOUGLAS
ELBERT    GILPIN       GRAND     JACKSON       JEFFERSON    LARIMER
LINCOLN   LOGAN        MORGAN    PARK          PHILLIPS     SEDGWICK
SUMMIT    WASHINGTON   WELD

SYNOPSIS: A WEAK COLD FRONT IS PUSHING INTO NORTHERN COLORADO THIS
AFTERNOON AND IS BECOMING THE FOCUS FOR THE DEVELOPMENT OF STRONG
STORMS.  OTHER STRONG STORMS ARE DEVELOPING ALONG THE PALMER DIVIDE.
IN ADDITION...THUNDERSTORMS CONTINUE TO DEVELOP OVER THE MOUNTAINS
AND ALONG THE FOOTHILLS.

WINDS IN THE UPPER ATMOSPHERE WHICH WILL STEER THESE STORMS ARE LIGHT.
AS A RESULT...ALL THE STORMS WILL BE SLOW MOVING...AND COULD DUMP
HEAVY RAIN IN ANY GIVEN PLACE IN A VERY SHORT TIME.

AGAIN...THE MAIN THREAT FROM THE STORMS WILL BE HEAVY RAIN...WHICH
COULD PRODUCE LOCAL FLOODING...AND SMALL HAIL.  BUT A FEW OF THE
STRONGER STORMS COULD PRODUCE HAIL UP TO ONE INCH.

A FORMAL SPOTTER NETWORK IS NOT ANTICIPATED...BUT RAIN >AND HAIL
REPORTS TO THE NATIONAL WEATHER SERVICE WILL BE APPRECIATED.

LESZCYNSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 14, 6:05 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld35 min
Jun 14, 7:35 PM MDTSevere Thunderstorm WarningBOUAdams, Washington25 min
Jun 14, 7:55 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick45 min
Jun 14, 8:52 PM MDTSevere Thunderstorm WarningBOULogan, Phillips, Sedgwick38 min
Jun 14, 9:38 PM MDTSevere Thunderstorm WarningBOUPhillips27 min
Jun 15, 12:33 AM MDTFlash Flood WarningBOUPhillips3 hr
Jun 15, 3:25 AM MDTFlash Flood WarningBOUPhillips2 hr
Jun 15, 5:23 AM MDTFlash Flood WarningBOUPhillips3 hr
Jun 15, 1:41 PM MDTSevere Thunderstorm WarningBOULarimer, Weld34 min
Jun 15, 3:20 PM MDTTornado WarningBOUAdams, Weld25 min
Jun 15, 3:20 PM MDTTornado WarningBOUBoulder25 min
Jun 15, 3:53 PM MDTSevere Thunderstorm WarningBOUAdams, Weld32 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1997Every severe thunderstorm warning in 1997

Sources

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