Alert archive / Colorado / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 26, NWS Denver/Boulder, CO

June 23, 1987Adams County, Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 23, 1987, 5:53 PM MDT for Adams County, Arapahoe County, Colorado. It was in force for 42 min.

The area

The counties it named.

The facts

Issued
Jun 23, 1987, 5:53 PM MDT (23:53 UTC)
Expired
Jun 23, 1987, 6:35 PM MDT
In force
42 min
Issued by
NWS Denver/Boulder, CO
Area
Whole counties

Counties Adams County, CO, 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, 11.9 hours before the alert went out and 95 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 1987-06-23Temperature 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 1987-06-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 31 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
964 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
31 m²/s²
0-3 km storm-relative helicity
149 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 23, 2:06 PM MDT, 3 hours 47 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
205 PM MDT TUE JUN 23 1987

...RAPID THUNDERSTORM DEVELOPMENT EXPECTED NORTH AND WEST DENVER METRO
   AREA...
...TORNADO WATCH IN EFFECT FOR MUCH OFEASTERN COLORADO...

A TORNADO WATCH IS NOW IN EFFECT FOR A LARGE PART OF COLORADO EAST OF
MOUNTAINS AND NORTH OF ABOUT THE ARKANSAS RIVER.

THUNDERSTORMS THAT HAVE BEGUN TO DEVELOP NEAR DENVER WILL INTENSIFY
BEFORE 3 PM. STRONGEST STORMS ARE LIKELY FROM NEAR BRIGHTON THRU THE
NORTHERN DENVER METRO AREA INTO EXTREME EASTERN JEFFERSON COUNTY. THE
STORMS WILL INTENSIFY RAPIDLY BETWEEN NOW AND 300 PM AND MAY BECOME
SEVERE.  BRIEF HEAVY RAINS ARE LIKELY WITH THE STORMS..

KAPLAN
Special weather statement, Jun 23, 5:41 PM MDT, 12 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DENVER CO
542 PM MDT TUE JUN 23 1987

...STRONG STORMS CONTINUE IN CENTRAL ADAMS AND APARAHOE COUNTIES
   AND NORTHWESTERN WELD COUNTY...
...TORNADO WATCH IN EFFECT FOR MUCH OF EASTERN COLORADO...

AT 540 PM MDT STRONGEST STORMS WERE IN CENTRAL ADAMS AND ARAPAHOE
COUNTIES NEAR BYERS AND STRASBURG. MARBLE SIZE HAIL WAS REPORTED IN
STRASBURG AROUND 530 PM MDT...ALONG WITH AN ESTIMATED 1 INCDH OF RAIN
IN 15 MINUTES.  THE WELD COUNTY STORM WASS NEAR NUNN AND IS ALSO
PRODUCING SOME HAIL AND HEAVY RAIN.  BOTH STORMS ARE TRACKING TO THE
EAST.

A TORNADO WATCH CONTINUES FOR MUCH OF EASTERN COLORADO TIM 8 PM MDT.
KAPLAN

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 23, 2:20 PM MDTTornado WarningBOUArapahoe, Douglas, Jefferson30 min
Jun 23, 2:20 PM MDTTornado WarningBOUDenver30 min
Jun 23, 2:34 PM MDTSevere Thunderstorm WarningBOUWeld56 min
Jun 23, 2:54 PM MDTSevere Thunderstorm WarningBOUArapahoe, Douglas61 min
Jun 23, 2:54 PM MDTSevere Thunderstorm WarningBOUAdams, Denver61 min
Jun 23, 3:17 PM MDTSevere Thunderstorm WarningBOUArapahoe, Douglas, Jefferson58 min
Jun 23, 3:17 PM MDTSevere Thunderstorm WarningBOUAdams, Denver, Weld58 min
Jun 23, 4:11 PM MDTSevere Thunderstorm WarningBOUAdams, Morgan, Weld59 min
Jun 23, 4:11 PM MDTSevere Thunderstorm WarningBOUArapahoe, Denver59 min
Jun 23, 5:59 PM MDTTornado WarningBOUWeld41 min

Nearby

Severe Thunderstorm Warnings in Colorado, 1987Every severe thunderstorm warning 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.