Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 63, NWS Des Moines, IA

June 21, 1987Dallas County, Madison County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jun 21, 1987, 6:59 PM CDT for Dallas County, Madison County, Iowa. It was in force for 46 min.

The area

The counties it named.

The facts

Issued
Jun 21, 1987, 6:59 PM CDT (23:59 UTC)
Expired
Jun 21, 1987, 7:45 PM CDT
In force
46 min
Issued by
NWS Des Moines, IA
Area
Whole counties

Counties Dallas County, IA, Madison County, IA

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

Omaha, NE (KOAX), launched 12:00Z, 12.0 hours before the alert went out and 196 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, Omaha, NE at 12:00Z on 1987-06-21Temperature 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 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 1987-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 46 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
3616 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
46 m²/s²
0-3 km storm-relative helicity
64 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 KDSM 220001
SVRDSM
IAC121-049-220045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
659 PM CDT SUN JUN 21 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 745 PM CDT FOR PEOPLE IN THE FOLLOWING
COUNTIES OF

SOUTH CENTRAL IOWA...
 MADISON AND EXTREME SOUTHERN DALLAS

AT 659 PM...WEATHER RADAR CONTINUED TO INDICATE A SEVERE
THUNDERSTORM OVER ALONG THE DALLAS/MADISON COUNTY LINE NEAR EARLHAM...
...ABOUT 30 MILES WEST OF DES MOINES.

THE STORM WAS MOVING SOUTHEAST AT 25 MILES AN HOUR...AND WILL
BE AFFECTING THE TOWNS OF EARLHAM...WINTERSET...AND PATTERSON.
WINDS OF 60 TO 70 MILES AN HOUR WERE REPORTED JUST NORTH OF EARLHAM AT
655 PM.

REMEMBER..A SEVERE THUNDERSTORM CAN PRODUCE DAMAGING WINDS IN EXCESS
OF 60 MPH..LARGE HAIL..DEADLY LIGHTNING..AND HEAVY RAINS THAT CAN
QUICKLY FLOOD LOW LYING AREAS.  PEOPLE IN THE PATH OF THIS STORM
SHOULD TAKE APPROPRIATE ACTION IMMEDIATELY.

IF THREATENING WEATHER APPROACHES..YOU SHOULD GO TO A SAFE PLACE
IMMEDIATELY.  IF SEVERE WEATHER CONDITIONS ARE OBSERVED..PLEASE ASK
THE NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR REPORT TO THE
NATIONAL WEATHER SERVICE.

KS/TRUETT

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 21, 6:25 PM CDTSevere Thunderstorm WarningDMXDallas, Guthrie35 min

Nearby

Severe Thunderstorm Warnings in Iowa, 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.