Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 13, NWS Des Moines, IA

May 19, 1987Decatur County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 19, 1987, 8:24 PM CDT for Decatur County, Iowa. It was in force for 66 min.

The area

The counties it named.

The facts

Issued
May 19, 1987, 8:24 PM CDT (01:24 UTC)
Expired
May 19, 1987, 9:30 PM CDT
In force
66 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Decatur 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 00:00Z, 1.4 hours before the alert went out and 226 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 00:00Z on 1987-05-20Temperature 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 00:00Z on 1987-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 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
3590 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
82 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 200124 RRA
SVRDSM
IAC159-053-200230-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
824 PM CDT TUE MAY 19 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 930 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES OF

SOUTH CENTRAL IOWA...
 EASTERN RINGGOLD AND SOUTHWEST DECATUR

AT 820 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM AT MOUNT AYR
ABOUT 20 MILES NORTHWEST OF LAMONI...IN SOUTH CENTRAL IOWA.

THE STORM WAS MOVING TO THE EAST AT 20 MILES AN HOUR.

THE CITIES OF MOUNT AYR...LAMONI...AND LEON ARE INCLUDED IN THIS
WARNING.

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.

THESE STORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE
OR NO ADVANCE WARNING..SO BE ON THE LOOKOUT AND BE PREPARED TO MOVE
TO A PLACE OF SAFETY IF ONE IS SPOTTED.

CORBETT

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, May 19, 5:07 PM CDT, 3 hours 17 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
440 PM CDT TUE MAY 19 1987

AT 430 PM...ISOLATED VERY STRONG THUNDERSTORMS HAD DEVELOPED OVER
EXTREME SOUTHWEST IOWA...BETWEEN SHENANDOAH...AND SOUTH OF CORNING.
THESE STORM WERE LOCATED ABOUT 50 MILES SOUTHEAST OF OMAHA.

THE STORMS COULD PRODUCE BRIEF HEAVY RAINS...FREQUENT LIGHTNING
AND SOME HAIL.

MOVEMENT AND SPEED OF THESE STORMS HAS YET BEEN DETERMINED.

MCQUIRjTER
Special weather statement, May 19, 7:34 PM CDT, 50 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
732 PM CDT TUE MAY 19 1987

...SEVERE THUNDERSTORM WATCH FOR SOUTHWEST IOWA UNTIL MIDNIGHT...

...NO SEVERE WEATHER HAS BEEN REPORTED IN IOWA BETWEEN 630 AND 730 PM...

AT 725 PM...INTENSE THUNDERSTORMS WERE LOCATED IN WEST CENTRAL AND
SOUTHWEST IOWA. ONE STORM WAS LOCATED 5 MILES NORTHEAST OF HARLAN...
70 MILES WEST OF DES MOINES. THIS STORM IS CAPABLE OF PRODUCING
VERY HEAVY RAIN...DANGEROUS LIGHTNING...SMALL HAIL AND GUSTY WINDS.
THE SECOND INTENSE STORM WAS LOCATED IN SOUTHWEST IOWA NEAR THE
CITY OF LENOX 55 MILES SOUTHWEST OF DES MOINES. THIS STORM IS ALSO
CAPABLE OF PRODUCING VERY HEAVY RAIN...SMALL HAIL...DANGEROUS
LIGHTNING AND GUSTY WINDS. THESE STORMS WERE PART OF A MUCH LARGER
AREA OF SHOWERS AND STORMS THAT COVERED THE SOUTHWEST QUARTER OF
IOWAS COUNTIES.

THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR...
THERE ^HAS BEEN LITTLE CHANGE IN INTENSITY BUT AN INCREASE IN AREAL
COVERAGE.

BARLOW/GOODSON

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 8:05 PM CDTSevere Thunderstorm WarningDMXGuthrie35 min
May 19, 8:24 PM CDTSevere Thunderstorm WarningDMXRinggold46 min
May 20, 3:27 PM CDTSevere Thunderstorm WarningDMXUnion33 min
May 20, 3:30 PM CDTSevere Thunderstorm WarningDMXDecatur30 min
May 20, 4:37 PM CDTSevere Thunderstorm WarningDMXLinn41 min
May 20, 5:49 PM CDTSevere Thunderstorm WarningDMXMahaska41 min
May 20, 6:05 PM CDTSevere Thunderstorm WarningDMXBlack Hawk20 min
May 20, 6:05 PM CDTSevere Thunderstorm WarningDMXBremer40 min
May 20, 6:20 PM CDTSevere Thunderstorm WarningDMXBremer60 min
May 20, 6:31 PM CDTSevere Thunderstorm WarningDMXTama19 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.