Alert archive / Iowa / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 39, NWS Des Moines, IA

May 31, 1987Dallas County, Iowa

NWS Des Moines, IA issued this severe thunderstorm warning at May 31, 1987, 4:31 PM CDT for Dallas County, Iowa. It was in force for 24 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued: May 31, 1987, 4:31 PM CDT (21:31 UTC)
Expired: May 31, 1987, 4:55 PM CDT
In force: 24 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Dallas County, IA

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

Time	Report	Where	Remark
May 31, 4:40 PM CDT	Tornado F0	Dallas, IA

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 9.5 hours before the alert went out and 198 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 3577 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 69 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 312132
SVRDSM
IAC049-312210-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
431 PM CDT SUN MAY 31 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 510 PM CDT FOR PEOPLE IN THE FOLLOWING
COUNTY OF

CENTRAL IOWA...
 NORTHERN DALLAS

AT 428 PM...RADAR INDICATED A SEVERE THUNDERSTORM OVER DALLAS
COUNTY 5 MILES WEST OF DALLAS CENTER...25 MILES NORTHWEST OF
DES MOINES.

THE STORM WAS MOVING NORTHEAST AT 30 MILES AN HOUR...AND WILL
BE AFFECTING THE CITIES OF MINBURN...DALLAS CENTER...AND GRANGER.
<
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.

SCOTT/TRUETT

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 31, 2:41 PM CDT, 1 hour 50 minutes before

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE DES MOINES IA
240 PM CDT SUN MAY 31 1987

....A SSVERE THUNDERSTORM WATCH IS IN EFFECT FOR PART OF EASTERN IOWA
UNTIL 900 PM TONIGHT...

AT 230 PM...ISOLATED STRONG THUNDERSTORMS WERE OCCURRING OVER SOUTHEAST
...SOUTHWEST...AND WEST CENTRAL IOWA.  THESE STORMS WERE LOCATED 20
MILES SOUTHWEST OF OTTUMWA...40 MILES NORTHWEST OF LAMONI...AND NEAR
GUTHRIE CENTER...WHICH IS 40 MILES WEST OF DES MOINES.

THESE STORMS WERE MOVING EAST AT 25 MILES AN HOUR.

ALSO...ISOLATED THUNDERSHOWERS AND RAINSHOWERS WERE OVER PARTS OF
SOUTHWEST AND SOUTHEAST IOWA.

THE AREA OF SHOWERS WAS MOVING NORTHEAST AT 20 MILES AN HOUR.

MILLER

The office that day

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

Issued	Product	Office	Counties	Lasted
May 31, 3:13 PM CDT	Severe Thunderstorm Warning	DMX	Union	34 min
May 31, 3:13 PM CDT	Severe Thunderstorm Warning	DMX	Adams	17 min
May 31, 4:00 PM CDT	Tornado Warning	DMX	Audubon, Cass	60 min
May 31, 4:22 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	38 min
May 31, 5:01 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Guthrie	59 min
May 31, 5:19 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Ringgold, Union	41 min
May 31, 5:37 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas	38 min
May 31, 6:13 PM CDT	Severe Thunderstorm Warning	DMX	Lucas	47 min
May 31, 6:25 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Monroe	50 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1987 Every 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.