Alert archive / Colorado / Tornado Warnings in 1987

Tornado Warning 5, NWS Denver/Boulder, CO

June 9, 1987Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at Jun 9, 1987, 4:41 PM MDT for Arapahoe County, Colorado. It was in force for 29 min.

The area

The counties it named.

The facts

Issued
Jun 9, 1987, 4:41 PM MDT (22:41 UTC)
Expired
Jun 9, 1987, 5:10 PM MDT
In force
29 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

County Arapahoe 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, 10.7 hours before the alert went out and 98 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 1987-06-09Temperature 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 1987-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 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
676 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
128 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 092243
TORDEN
COC005-092310-
 
BULLETIN...EBS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DENVER CO
441 PM MDT TUE JUN 09 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING
EFFECTIVE UNTIL 510 PM  MDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF NORTHEAST COLORADO:
 
     SOUTHWESTERN ARAPAHOE
 
INCLUDING THE FOLLOWING TOWNS/CITIES:
 
     SOUTHERN HALF OF AURORA
 
THE STORM IS LOCATED OVER SOUTHERN  AURORA 

AT 440PM MDT A FUNNEL CLOUD WAS REPORTED OVER THE INTERSECTION
OF ILIFF AND BUCKLEY AVENUES IN AURORA BY AN OFF DUTY WEATHER
FORECASTER.  

IN HOME...GO TO A BASEMENT OR IF NO BASEMENT IS AVAILABLE GO
TO A FULLY ENCLOSED INTERIOR ROOM ON THE LOWEST FLOOR.
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.
 
THIS THUNDERSTORM MAY ALSO CAUSE FLOODING DUE TO VERY HEAVY RAIN.
 
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.
 
LAT..LON  3956 10492 3969 10487 3972 10467 3956 10466

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 9, 12:14 PM MDT, 4 hours 27 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
1210PM MDT   TUESDAY   JUNE 9 1987

             ...HEAVY RAIN IN MORGAN COUNTY COLORADO...

RADAR SHOWS A BAND OF HEAVY SHOWERS LOCATED OVER WESTERN MORGAN COUNTY.
THIS BAND IS VERY NARROW AND IS LOCATED FROM GOODRICH AND JACKSON
RESERVOIR TO ABOUT WIGGINS COLORADO.  A SPOTTER AT JACKSON LAKE REPORTED
VERY HEAVY RAIN AT NOON WITH 2 INCHES THUS FAR.  THESE SHOWERS HAVE
SHOWN VERY LITTLE MOVEMENT SINCE THEY FORMED.

PERSONS IN WESTERN MORGAN COUNTY SHOULD AVOID LOW LYING AREAS AND SMALL
STREAMS AS THIS HEAVY RAIN MAY CAUSE LOCAL FLOODING.  MOTORISTS ON I-76
AND OTHER ROADS SHOULD DRIVE WITH CAUTION AND AVOID UNDERPASSES AND BE
ALERT FOR FLOODING OF STREET INTERSECTIONS.  ALL PERSONS IN ESSTERN
COLORADO SHOULD CONTINUE TO MONITOR LOCAL RADIO AND TV BROADCASTS OR
NOAA WEATHER RADIO FOR FUTURE STATEMENTS AND WARNINGS.  A FLASH FLOOD
WATCH REMAINS POSTED FOR THE EASTERN FOOTHILLS AND ADJACENT PLAINS
BELOW 7000 FEET FOR THIS AFTERNOON AND EVENING.
Special weather statement, Jun 9, 1:11 PM MDT, 3 hours 30 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
110PM MDT TUESDAY   JUNE 9 1987

             ...LOCALLY HEAVY RAINS CONTINUE IN EASTERN COLORADO...

HEAVY THUNDERSTORMS CONTINUE IN MORGAN COUNTY WITH THE HEAVIEST STORM
AT 1PM REPORTED 10 MILES SOUTHWEST OF FORT MORGAN. LOCALLY HEAVY
SHOWERS AND THUNDERSTORMS ARE ARE DEVELOPING THROUGHOUT MUCH OF EASTERN
COLORADO AND DURING THE PAST HOUR HAVE BEGUN FORMING ALONG THE EASTERN
FOOTHILLS. THESE STORMS ARE MOVING MOSTLY TOWARD THE NORTH NORTHEAST
AT AROUND 10 TO 20 MILES PER HOUR.

THE FLASH FLOOD WATCH VALID FROM 3PM TO 9PM THIS AFTERNOON ALONG
MUCH OF THE EASTERN FOOTHILLS BELOW 7500 FEET REMAINS IN EFFECT.
STAY TUNED TO RADIO OR TV FOR FURTHER INFORMATION.

TUNNELL
Special weather statement, Jun 9, 2:44 PM MDT, 1 hour 57 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE  DENVER CO
3PM MDT TUESDAY   JUNE 9 1987

             ...WIDESPREAD RAIN OVER EASTERN COLORADO...

LOCALLY HEAVY SHOWERS AND THUNDERSTORMS CONTINUED OVER EASTERN
COLORADO AT 3PM WITH THE HEAVIEST STORM 3 MILES SOUTHEAST OF MERINO
IN LOGAN COUNTY. OTHER HEAVY SHOWERS WERE SPOTTED THROUGHOUT THE EASTERN
PLAINS AND WERE BEGINNING TO DEVELOP IN WESTERN JEFFERSON COUNTY. THESE
STORMS ARE MOVING MOSTLY TOWARD THE NORTH AT AROUND 15 TO 20 MILES PER
HOUR.

THE FLASH FLOOD WATCH VALID FROM 3PM TO 9PM THIS AFTERNOON ALONG
MUCH OF THE EASTERN FOOTHILLS BELOW 7500 FEET REMAINS IN EFFECT.
STAY TUNED TO RADIO OR TV FOR FURTHER INFORMATION.

TUNNELL


The office that day

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

IssuedProductOfficeCountiesLasted
Jun 9, 3:30 PM MDTSevere Thunderstorm WarningBOUDenver60 min
Jun 9, 3:30 PM MDTSevere Thunderstorm WarningBOUArapahoe, Douglas, Jefferson60 min
Jun 9, 4:11 PM MDTTornado WarningBOUAdams, Arapahoe29 min
Jun 9, 4:17 PM MDTTornado WarningBOUArapahoe, Douglas28 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.