Alert archive / Colorado / Tornado Warnings in 1987

Tornado Warning 11, NWS Denver/Boulder, CO

June 28, 1987Arapahoe County, Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 28, 1987, 4:47 PM MDT for Arapahoe County, Washington County, Colorado. It was in force for 18 min.

The area

The counties it named.

The facts

Issued
Jun 28, 1987, 4:47 PM MDT (22:47 UTC)
Expired
Jun 28, 1987, 5:05 PM MDT
In force
18 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Arapahoe County, CO, Washington County, CO

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Denver, CO (KDEN), launched 12:00Z, 10.8 hours before the alert went out and 47 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 1987-06-28Temperature 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 1987-06-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
2946 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
48 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 282249
TORDEN
COC121-005-039-073-282305-
 
BULLETIN...EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
447 PM MDT SUN JUN 28 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 505 PM  MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF NORTHEAST COLORADO:
 
     SOUTHWESTERN WASHINGTON
     SOUTHEASTERN ARAPAHOE
     NORTHEASTERN ELBERT
     NORTHERN LINCOLN
 
INCLUDING THE FOLLOWING TOWNS/CITIES:
 
     AGATE
 
THE STORM IS LOCATED 24 MILES NORTH OF LIMON.
 
AT445PM A TORNADO WAS REPORTED BY PERSONS JUST NORTH OF LIMON
 
IN HOMES GO TO THE BASEMENT OR INTO A CLOSET OR BATHROOM.
IN SCHOOLS..HIGH RISES AND HOSPITALS GO TO AN INTERIOR
HALLWAY ON THE LOWEST FLOOR.  IF IN MOBILE HOMES OR VEHICLES..
EVACUATE THEM AND GO TO A SUBSTANTIAL SHELTER.  IF NO SHELTER
IS AVAILABLE..LIE FLAT IN THE NEAREST DITCH OR OTHER LOW SPOT.
IN ALL CASES..STAY AWAY FROM WINDOWS..DOORS AND OUTSIDE WALLS.
 
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR 
 
TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT
AGENCY RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE OFFICE
IN DENVER..OR CALL YOUR REPORT TO THE NATIONAL WEATHER SERVICE
AT 361-0663.  DO NOT CALL THIS NUMBER FOR INFORMATION.
 
DUNN
 
LAT..LON  3965 10381 3967 10356 3950 10311 3930 10387

What forecasters said that day

The local office's own words before this tornado 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 28, 12:10 PM MDT, 4 hours 37 minutes before
SPECIAL WEATHER STATEMENT/SHORT RANGE FORECAST
NATIONAL WEATHER SERVICE DENVER CO
1207 PM MDT SAT JUN 27 1987

....STRONG THUNDERSTORM NORTH OF FT COLLINS...

AS OF 1205 PM MDT A STRONG THUNDERSTORM HAD DEVELOPED ABOUT 20 MILES
NORTHEAST OF FORT COLLINS COLORADO...NEAR THE TOWN OF WARREN.  THIS
STORM SHOULD MOVE SOUTHEAST AND MAY BRING BRIEF HEAVY RAIN...SMALL HAIL
AND STRONG GUSTY WINDS TO CARR...NUNN AND DOVER BETEWEEN NOW AND 130 PM
MDT.

THIS STORM IS PROBABLY THE BEGINNINGS OF A LINE OF STORMS WHICH IS
EXPECTED TO DEVELOP NEAR THE WYOMING BORDER EARLY THIS AFTERNOON AND
MOVE SOUTHWARD AHEAD OF A COLD FRONT.  THE STORMS MAY BECOME
SEVERE...ESPECIALLY ON THE NORTHEAST PLAINS.

KAPLA
Local storm report, Jun 28, 2:31 PM MDT, 2 hours 16 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
225 PM MDT SUN JUN 28 1987

TIME       EVENT/LOCATION
1413       NR GALETON CO...3/4 INCH HAIL, PARTLY MELTED, FROM RECENT
           STORM.  REPORT FROM PROFS CHASE TEAM.

KAPLAN
Special weather statement, Jun 28, 2:49 PM MDT, 1 hour 58 minutes before
SPECIAL WEATHER STATEMENT/SHORT RANGE FORECAST
NATIONAL WEATHER SERVICE DENVER CO
248 PM MDT SAT JUN 27 1987

....THUNDERSTORMS BUILDING AROUND DENVE METRO AREA..

AT 240 PM MDT CLOUDS WERE BUILDING FROM BOULDER THROUGH DENVER AND
EASTWARD IN AN AREA  OF CONVERGING WINDS.  THESE CONVERGING WINDS SHOULD
INTENSIFY AND THE CLOUDS BUILD INTO THUNDERSTORMS BY AROUND 3PM OR
SHORTLY AFTER. THESE SHOWERS AND THUNDERSTORMS WILL PRODUCE STRONG WIND
G
Special weather statement, Jun 28, 3:21 PM MDT, 1 hour 26 minutes before
SPECIAL WEATHER STATEMENT/SHORT RANGE FORECAST
NATIONAL WEATHER SERVICE DENVER CO
320 PM MDT SUN JUN 28 1987

....STRONG THUNDERSTORM NEAR AKRON,COLORADO....

A STRONG THUNDERSTORM WAS INDICATED ON RADAR AT 315PM VERY NEAR AKRON IN
WESTERN WASHINGTON COUNTY. THIS STORM WAS MOVING VERY SLOWLY TO THE
EAST.  HEAVY RAIN WITH FLOODING OF LOW LYING AREAS AND SMALL HAIL ARE
LIKELY IN THIS AREA.

FURTHER STATEMENTS OR WARNINGS WILL BE ISSUED AS NEEDED...LPERSONS IN
WASHINGTON COUNTY SHOULD STAY TUNED TO LOCAL MEDIA OR NOAA WEATHER RADIO
FOR THE NEXT FEW HOURS.

DUNN

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 1:14 PM MDTSevere Thunderstorm WarningBOUMorgan, Weld61 min
Jun 28, 3:27 PM MDTSevere Thunderstorm WarningBOUWashington63 min
Jun 28, 5:06 PM MDTSevere Thunderstorm WarningBOUWashington, Yuma59 min
Jun 28, 5:06 PM MDTSevere Thunderstorm WarningBOUArapahoe59 min

Nearby

Tornado Warnings in Colorado, 1987Every tornado warning in 1987Tornadoes in 1987

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.