Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 5, NWS Des Moines, IA

May 2, 1987Jasper County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 2, 1987, 5:23 PM CDT for Jasper County, Iowa. It was in force for 27 min.

The area

The counties it named.

The facts

Issued
May 2, 1987, 5:23 PM CDT (22:23 UTC)
Expired
May 2, 1987, 5:50 PM CDT
In force
27 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Jasper 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, 10.4 hours before the alert went out and 279 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 1987-05-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 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 1987-05-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 km3 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
3602 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
40 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 022223
SVRDSM
IAC099-022315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
523 PM CDT SAT MAY 2 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 615 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

CENTRAL IOWA...
 EASTERN JASPER

AT 517 PM CDT RADAR INDICATED A SEVERE THUNDERSTORM IN CENTRAL
JASPER COUNTY...ABOUT 30 MILES TO THE EAST OF DES MOINES.

THE STORM WAS MOVING EAST AT 15 MILES AN HOUR AND SOME OF THE
CITIES IT WILL MOVE INTO ARE NEWTON AND KELLOGG BETWEEN 525 PM
AND 545 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.

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

WEINBRECHT/KS

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 2, 2:46 PM CDT, 2 hours 37 minutes before
<PQ<
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
245 PM CDT SATURDAY MAY 2 1987

...THUNDERSTORMS MOVING INTO DES MOINES AND AMES...

THUNDERSTORMS HAVE BEEN DEVELOPING TO THE WEST OF DES MOINES
AND AMES AND ARE NOW MOVING INTO THESE MUNICIPALITIES.  MOST
REPORTS RECEIVED HAVE ONLY INCLUDED HEAVY RAINS WITH THESE STORMS
...BUT PEA SIZE HAIL WAS OBSERVED AT WAUKEE AT APPROXIMATELY 230 PM.

THESE THUNDERSTORMS ARE ALSO CAPABLE OF PRODUCING WIND GUSTS IN THE
RANGE OF 30 TO 35 MILES AN HOUR.  THUS IT IS RECOMMENDED THAT BOATERS
AND SWIMMERS ON AREA LAKES...INCLUDING SAYLORVILLE LAKE...HEAD IN FOR
SHORE BEFORE THESE STORMS ARRIVE.  LIGHTNING SAFETY PRECAUTIONS NEED
ALSOY BE OBSERVED.

DOWD

The office that day

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

IssuedProductOfficeCountiesLasted
May 2, 3:32 PM CDTTornado WarningDMXPolk38 min
May 2, 4:10 PM CDTSevere Thunderstorm WarningDMXPolk50 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.