Alert archive / Colorado / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 63, NWS Denver/Boulder, CO

June 18, 1997Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 18, 1997, 4:03 PM MDT for Weld County, Colorado. It was in force for 27 min. No storm report in the archive falls 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.

The facts

Issued
Jun 18, 1997, 4:03 PM MDT (22:03 UTC)
Expired
Jun 18, 1997, 4:30 PM MDT
In force
27 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 68 km from the middle of the area, began a volume at 22:05 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 watch it was issued in

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

IssuedProductOfficeLasted
Jun 18, 3:15 PM MDTTornado WatchSPC6 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.1 hours before the alert went out and 133 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 1997-06-18Temperature 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 1997-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 86 square meters per square second.1939Sfc1 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
2353 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
86 m²/s²
0-3 km storm-relative helicity
100 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 182204 RRA
SVRDEN
COC123-182230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
403 PM MDT WED JUN 18 1997

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A SEVERE
THUNDERSTORM WARNING EFFECTIVE UNTIL 430 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES...

IN NORTHEAST COLORADO
     NORTH CENTRAL WELD

INCLUDING THE FOLLOWING LOCATIONS
     GROVER...HEREFORD AND PAWNEE BUTTES

AT 356 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM 3 MILES SOUTHEAST OF HEREFORD...OR ABOUT 44 MILES
NORTHEAST OF GREELEY.

AT 356 PM MDT THE PUBLIC REPORTED 3/4 INCH HAIL IN HEREFORD.

THE STORM WAS MOVING EAST AT 25 MILES PER HOUR AND WILL CONTINUE 
PRODUCING HAIL UP TO ONE INCH IN DIAMETER THROUGH 430 PM. 

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF NORTHEASTERN COLORADO 
UNTIL 9 PM MDT.

INTENSE LIGHTNING IS OCCURRING WITH THIS STORM. IF OUTDOORS...STAY
AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE INDOORS IF
POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS AND AVOID
USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG UNNECESSARY
ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.

REPORTH 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 4079 10390 4080 10433 4099 10440 4099 10390
&

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 18, 11:02 AM MDT, 5 hours 1 minute before
COZ030-032>050-190600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1105 AM MDT WED JUN 18 1997

THIS OUTLOOK PERTAINS TO THE FOLLOWING COLORADO
Special weather statement, Jun 18, 11:05 AM MDT, 4 hours 58 minutes before
COZ030-032>050-190600-

SIGNIFICANT WEATHER OUTLOOK FOR NORTHEAST AND NORTH CENTRAL COLORADO
NATIONAL WEATHER SERVICE DENVER CO
1105 AM MDT WED JUN 18 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: AN APPROACHING UPPER LEVEL DISTURBANCE WILL HELP
DESTABILIZE THE ATMOSPHERE AND ALLOW ISOLATED THUNDERSTORMS
TO DEVELOP OVER THE PLAINS BY LATE AFTERNOON AND CONTINUE UNTIL NEAR
MIDNIGHT.  THE THUNDERSTORM ACTIVITY WILL DEVELOP A LITTLE EARLIER
OVER THE MOUNTAINS AND THEN MOVE ON TO THE PLAINS. THE MAIN THREAT
FROM THE POTENTIAL STORMS IS HAIL AND GUSTY WINDS. STRONG WINDS IN
THE MID LEVELS WILL KEEP THE STORMS MOVING RATHER QUICKLY AND
INHIBIT THE THREAT OF HEAVY RAIN. MAXIMUM RAINFALL AMOUNTS WILL BE
AROUND ONE-HALF OR THREE-QUARTERS OF AN INCH IN AN HOUR.

SPOTTER ACTIVATION MAY BE NEEDED BY LATE AFTERNOON.

HERALD/BOODA
Special weather statement, Jun 18, 2:25 PM MDT, 1 hour 38 minutes before
COZ035-038-043-182100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
225 PM MDT WED JUN 18 1997

...THUNDERSTORMS DEVELOPING IN EASTERN LARIMER AND WESTERN WELD
COUNTIES THIS AFTERNOON...

AT 210 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 7 MILES NORTH OF BUCKEYE...OR ABOUT 22 MILES NORTH OF
FORT COLLINS.  THE PUBLIC REPORTED FUNNEL CLOUDS WITH THIS STORM.
THE STORM WAS MOVING EAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR FORT COLLINS...GREELEY...AULT...BELLVUE...CARR...
EATON...EVANS...GALETON...HARMONY...JOHNSTOWN...LA SALLE...LIVERMORE
...LOVELAND...LUCERNE...MASONVILLE...MILLIKEN...NATURAL FORT REST
AREA...NUNN...PIERCE...POUDRE PARK...PURCELL...ROCKPORT... EVERANCE
..TEDS PLACE...TIMNATH...VIRGINIA DALE...WELLINGTON AND WINDSOR
SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE
OF SAFETY IF BAD WEATHER APPROACHES.

RJK
Special weather statement, Jun 18, 2:27 PM MDT, 1 hour 36 minutes before
COZ035-038-043-182100-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
225 PM MDT WED JUN 18 1997

...THUNDERSTORMS DEVELOPING IN EASTERN LARIMER AND WESTERN WELD
COUNTIES THIS AFTERNOON...

AT 210 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 7 MILES NORTH OF BUCKEYE...OR ABOUT 22 MILES NORTH OF
FORT COLLINS.  THE PUBLIC REPORTED FUNNEL CLOUDS WITH THIS STORM.
THE STORM WAS MOVING EAST AT 20 MILES PER HOUR.

PERSONS IN OR NEAR FORT COLLINS...GREELEY...AULT...BELLVUE...CARR...
EATON...EVANS...GALETON...HARMONY...JOHNSTOWN...LA SALLE...LIVERMORE
...LOVELAND...LUCERNE...MASONVILLE...MILLIKEN...NATURAL FORT REST
AREA...NUNN...PIERCE...POUDRE PARK...PrURCELL...ROCKPORT... EVERANCE
..TEDS PLACE...TIMNATH...VIRGINIA DALE...WELLINGTON AND WINDSOR
SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE
OF SAFETY IF BAD WEATHER APPROACHES.

RJK
Special weather statement, Jun 18, 3:44 PM MDT, 19 minutes before
COZ038-042-182230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
344 PM MDT WED JUN 18 1997

...THUNDERSTORMS MOVING ALONG THE COLORADO/WYOMING BORDER...

AT 339 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 10 MILES WEST OF GROVER...OR ABOUT 37 MILES NORTHEAST OF
GREELEY.  ANOTHER STORM WAS OVER THE WELD/LARIMER COUNTY LINE.

THE STORMS WERE MOVING EAST AT 25 MILES PER HOUR.

PERSONS IN OR NEAR CARR...GROVER AND ROCKPORT SHOULD BE ON THE
LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD
WEATHER APPROACHES.  HAIL UP TO A HALF INCH IN DIAMETER...BRIEF
HEAVY RAIN AND WIND GUSTS UP TO 35 MPH ARE POSSIBLE AS THE
THUNDERSTORM MOVES.

INTENSE LIGHTNING IS BEING DETECTED WITH THIS STORM. IF
OUTDOORS...STAY AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE
INDOORS IF POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS
AND AVOID USING TELEPHONES UNLESS IT IS AN EMERGENCY. TRY TO UNPLUG
UNNECESSARY ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF NORTHEASTERN COLORADO
UNTIL 9 PM MDT.

DANKERS
Special weather statement, Jun 18, 3:45 PM MDT, 18 minutes before
COZ038-042-182230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
344 PM MDT WED JUN 18 1997

...THUNDERSTORMS MOVING ALONG THE COLORADO/WYOMING BORDER...

AT 339 PM MDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
THUNDERSTORM 10 MILES WEST OF GROVER...OR ABOUT 37 MILES NORTHEAST OF
GREELEY.  ANOTHER STORM WAS OVER THE WELD/LARIMER COUNTY LINE.

THE STORMS WERE MOVING EAST AT 25 MILES PER HOUR.

PERSONS IN OR NEAR CARR...GROVER AND ROCKPORT SHOULD BE ON THE
LOOKOUT FOR THREATENING WEATHER AND MOVE TO A PLACE OF SAFETY IF BAD
WEATHER APPROACHES.  HAIL UP TO A HALF INCH IN DIAMETER...BRIEF
HEAVY RAIN AND WIND GUSTS UP TO 35 MPH ARE POSSIBLE AS THE
THUNDERSTORM MOVES.

INTENSE LIGHTNING IS BEING DETECTED WITH THIS STORM. IF
OUTDOORS...STAY AWAY FROM ISOLATED HIGH OBJECTS SUCH AS TREES. MOVE
INDOORS IF POSSIBLE. WHEN INDOORS...STAY AWAY FROM WINDOWS AND DOORS
AND AVOID USING TELEPHONES UNLESS IT IS AN EM&ERGENCY. TRY TO UNPLUG
UNNECESSARY ELECTRICAL APPLIANCES BEFORE THE THUNDERSTORM APPROACHES.

A TORNADO WATCH REMAINS IN EFFECT FOR MOST OF NORTHEASTERN COLORADO
UNTIL 9 PM MDT.

DANKERS

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 18, 4:41 PM MDTSevere Thunderstorm WarningBOULogan, Weld34 min
Jun 18, 4:49 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver41 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.