Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 52, NWS Des Moines, IA

June 17, 1987Decatur County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at Jun 17, 1987, 12:31 PM CDT for Decatur County, Iowa. It was in force for 44 min.

The area

The counties it named.

The facts

Issued
Jun 17, 1987, 12:31 PM CDT (17:31 UTC)
Expired
Jun 17, 1987, 1:15 PM CDT
In force
44 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 12:00Z, 5.5 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 12:00Z on 1987-06-17Temperature 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 1987-06-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -101 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
3629 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-101 m²/s²
0-3 km storm-relative helicity
-76 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 171731 RRA
SVRDSM
IAC053-171815-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1231 PM CDT WED JUN 17 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 115 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

SOUTH CENTRAL IOWA...
 DECATUR

AT 1225 PM CDT...WEATHER RADAR IN DES MOINES INDICATED A SEVERE
THUNDERSTORM OVER SOUTHWEST DECATUR COUNTY NEAR LAMONI.

THE STORM WAS MOVING EAST AT 20 TO 25 MPH...AND WILL MOVE INTO
THE LEON AREA BETWEEN 1245 AND 100 PM THIS AFTERNOON.

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.

SCHUMACHER/BARLOW

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 17, 8:46 AM CDT, 3 hours 45 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
845 AM CDT WED JUN 17 1987

AT 835 AM...STRONG THUNDERSTORMS HAD RAPIDLY DEVELOPED OVER A SMALL
PART OF NORTHWEST IOWA. THIS CLUSTER OF THUNDERSTORMS WAS LOCATED
IN AND AROUND THE SPENCER...EMMETSBURG AND SPIRIT LAKE AREAS.

PEOPLE ON AREA LAKES IN NORTHWEST IOWA...SHOULD BE ALERT TO RAPIDLY
DEVELOPING THEN DISSIPATING STORMS. THIS RAPID DEVELOPMENT COULzD
CAUSE STRONG GUSTY WINDS.

ELSEWHERE AN AREA OF LIGHTER SHOWERS AND THUNDERSHOWERS WERE MOVING
INTO EXTREME NORTHWEST IOWA NORTH OF THE SIOUX CITY AREA.

THE THUNDERSTORMS WERE MOVING NORTHEAST AT 25 TO 30 MILES AN HOUR.

BARLOW
Special weather statement, Jun 17, 9:48 AM CDT, 2 hours 43 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
945 AM CDT WED JUN 17 1987

AT 935 AM...A 35 MILE WIDE BAND OF NUMEROUS SHOWERS AND ISOLATED
STRONG THUNDERSTORMS WAS LOCATED FROM 20 MILES NORTHEAST OF
ESTHERVILLE...ALONG THE IOWA/MINNESOTA BORDER SOUTH TO 50 MILES
NORTHWEST OF DES MOINES NEAR COON RAPIDS.

THE STRONGEST STORMS WERE LOCATED NEAR ALGONA...FORT DODGE AND
JEFFERSON...45 MILES NORTHWEST OF DES MOINES.

BRIEF HEAVY RAIN...GUSTY WINDS AND SOME SMALL HAIL IS POSSIBLE
WITH THESE STORMS.

THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR...
WITH AN INCREASE IN COVERAGE AND INTENSITY.

BARLOW
Special weather statement, Jun 17, 10:47 AM CDT, 1 hour 44 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1045 AM CDT WED JUN 17 1987

AT 1035 AM...A 35 MILE WIDE BAND OF NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS WAS LOCATED FROM CENTRAL IOWA...35 MILES NORTH OF
DES MOINES...NEAR BOONE NORTH TO BUFFALO CENTER...25 MILES
NORTHWEST OF MASON CITY...ALONG THE IOWA/MINNESOTA BORDERS.

ANOTHER AREA OF SHOWERS AND ISOLATED THUNDERSTORMS HAD 30 TO 45
MILES SOUTHWEST OF DES MOINES...NEAR THE CITIES OF GREENFIELD...
CRESTON AND ADAIR.

ISOLATED SHOWERS AND THUNDERSHOWERS HAD ALSO DEVELOPED IN NORTHEAST
IOWA...20 TO 25 MILES NORTHEAST OF MASON CITY...NEAR OSAGE.

THE SHOWERS AND THUNDERSTORMS WERE MOVIN$G NORTHEAST AT 25 MILES AN HOUR.

BARLOW
Special weather statement, Jun 17, 10:51 AM CDT, 1 hour 40 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY...CORRECTED
NATIONAL WEATHER SERVICE DES MOINES IA
1045 AM CDT WED JUN 17 1987

AT 1035 AM...A 35 MILE WIDE BAND OF NUMEROUS SHOWERS AND ISOLATED
THUNDERSTORMS WAS LOCATED FROM CENTRAL IOWA...35 MILES NORTH OF
DES MOINES...NEAR BOONE NORTH TO BUFFALO CENTER...25 MILES
NORTHWEST OF MASON CITY...ALONG THE IOWA/MINNESOTA BORDERS.

ANOTHER AREA OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPED HAD 30
TO 45 MILES SOUTHWEST OF DES MOINES...NEAR THE CITIES OF GREENFIELD....
CRESTON AND ADAIR.

ISOLATED SHOWERS AND THUNDERSHOWERS HAD ALSO DEVELOPED IN NORTHEAST
IOWA...20 TO 25 MILES NORTHEAST OF MASON CITY...NEAR OSAGE.

THE SHOWERS AND T*HUNDERSTORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR.

BARLOW
Special weather statement, Jun 17, 11:50 AM CDT, 41 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
1148 AM CDT WED JUN 17 1987

AT 1135 AM...TWO AREAS OF SHOWERS AND ISOLATED STRONG THUNDERSTORMS
PERSISTED OVER IOWA. THE FIRST AREA WAS LOCATED OVER NORTH CENTRAL
IOWA...WITH MOST OF THE PRECIPITATION OCCURRING BETWEEN THE ALGONA AND
THE MASON CITY AREAS. THE STRONGEST STORMS IN THAT AREA WERE LOCATED
JUST NORTHEAST OF MASON CITY. BRIEF HEAVY RAIN...GUSTY WINDS AND SMALL
HAIL IS POSSIBLE WITH THESE STORMS. THE SECOND AREA OF SHOWERS AND
STORMS WAS LOCATED IN A 25 MILE WIDE BAND FROM JUST WEST OF DES MOINES
SOUTH TO LAMONI. THE STORMS IN THIS AREA WERE MORE NUMEROUS AND WERE
PRODUCING SMALL HAIvL ALONG WITH BRIEF HEAVY RAIN AND GUSTY WINDS.

THE SHOWERS AND STORMS WERE MOVING NORTHEAST AT 20 TO 25 MILES AN
HOUR...AND THERE HAS BEEN A DECREASE IN OVERALL COVERAGE.

BARLOW
Special weather statement, Jun 17, 12:13 PM CDT, 18 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE WATERLOO IA
1215 PM CDT WED JUN 17 1987

...VERY STRONG THUNDERSTORMS IN NORTH CENTRAL IOWA...

AT 1210 PM CDT WATERLOO RADAR SHOWED AN AREA OF VERY STRONG THUNDERSTORMS
IN EASTERN CERRO GORDO..AND EASTERN WORTH COUNTIES OF IOWA...FROM 25
MILES NORTHEAST OF MASON CITY TO 25 MILES SOUTHEAST OF MASON CITY.

THESE THUNDERSTORMS COULD PRODUCE VERY HEAVY RAIN...STRONG GUSTY SURFACE
WINDS AND POSSIBLY SMALL HAIL.

THESE THUNDERSTORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR.

IF YOU ARE IN THE PATH OF THESE STORMS YOU SHOULD BE ALERT FOR
RAPIDLY CHANGING WEATHER CONDITIONS.
JOHNSON

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 17, 12:05 PM CDTSevere Thunderstorm WarningDMXPolk35 min
Jun 17, 12:22 PM CDTSevere Thunderstorm WarningDMXFloyd, Mitchell68 min
Jun 17, 12:40 PM CDTSevere Thunderstorm WarningDMXJasper35 min
Jun 17, 1:06 PM CDTSevere Thunderstorm WarningDMXMarshall34 min
Jun 17, 2:30 PM CDTSevere Thunderstorm WarningDMXButler, Franklin60 min
Jun 17, 3:25 PM CDTSevere Thunderstorm WarningDMXFayette65 min
Jun 17, 3:44 PM CDTSevere Thunderstorm WarningDMXBuchanan61 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.