Alert archive / Iowa / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 10, NWS Sioux Falls, SD

April 26, 1986Monona County, Iowa

NWS Sioux Falls, SD issued this severe thunderstorm warning at Apr 26, 1986, 8:01 PM CST for Monona County, Iowa. It was in force for 59 min.

The area

The counties it named.

The facts

Issued
Apr 26, 1986, 8:01 PM CST (02:01 UTC)
Expired
Apr 26, 1986, 9:00 PM CST
In force
59 min
Issued by
NWS Sioux Falls, SD
Area
Whole counties

County Monona 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, 2.0 hours before the alert went out and 88 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 1986-04-27Temperature 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 1986-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 155 square meters per square second.19395878Sfc1 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
3558 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
155 m²/s²
0-3 km storm-relative helicity
291 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 KSUX 270210 COR
SVRSUX
IAC133-270300-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING...CORRECTION
NATIONAL WEATHER SERVICE SIOUX CITY IA
801 PM CST SAT APR 26 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 900 PM CST FOR PEOPLE IN THE FOLLOWING
COUNTY OF

WEST CENTRAL IOWA...MONONA

AT 753 PM CST GOLFBALL SIZE HAIL WAS REPORTED IN LITTLE SIOUX IOWA
OR 45 MILES SOUTH OF SIOUX CITY IOWA BY THE LITTLE SIOUX POLICE.

THIS STORM WAS MOVING TO THE NORTHEAST AT 35 MILES AN HOUR AND WILL
MOVE INTO SOUTHERN MONONA COUNTY BY 810 PM CST.

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.

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.

PLEASE ASK THEn NEAREST LAW ENFORCEMENT AGENCY TO RELAY YOUR
REPORT OF SEVERE WEATHER TO THE NATIONAL WEATHER SERVICE.

ROSNER

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, Apr 26, 4:51 PM CST, 3 hours 10 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
440 PM CST SAT APR 26 1986

AT 430 PM CST...NUMEROUS INTENSE THUNDERSTORMS WERE OCCURRING IN
SOUTHEAST SOUTH DAKOTA. THE STORMS WERE IN A 45 MILE WIDE AREA
FROM 30 MILES SOUTHWEST OF SIOUX FALLS TO 50 MILES NORTHWEST OF
YANKTON.

LARGE HAIL AND STRONG WIND IS LIKELY IN THE AREA SOUTH OF A LINE
SIOUX FALLS TO CHAMBERLAIN..WHICH IS 65 MILES SOUTHEAST OF PIERRE.

THESE STORMS WERE MOVING NORTHEAST AT 25 MILES AN HOUR.

ALSO...NUMEROUS SHOWERS AND THUNDERSTORMS...SOME WITH VERY HEAVY
RAIN...CONTINUED OVER CENTRAL AND NORTHEAST SOUTH DAKOTA. THE
HEAVIEST RAIN WAS ALONG AND EAST OF THE JAMES RIVER AND NORTH OF
A LINE FROM HURON TO BROOKINGS.

THESE SHOWERS AND THUNDERSTORMS WERE MOVING NORTH AT 40 MILES AN
HOUR.

SPRINGER
Special weather statement, Apr 26, 5:43 PM CST, 2 hours 18 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SIOUX CITY IA
540 PM CST SAT APR 26 1986

    ..TORNADO WATCH TIL 9 PM ......

AT 535 PM CST THERE WAS A LARGE AREA OF THUNDERSTORMS SOME SEVERE
LOCATED 10 MILES SOUTHWEST OF SIOUX CITY TO LINCOLN NEBRASKA TO 20
MILES SOUTHWEST OF NORFOLK NEBRASKA. SOME SEVERE WEATHER HAS BEEN REPORTED
AT NORFOLK NEBRASKA BUT NONE HAS BEEN IN THE SIOUXLAND AREA.
THIS AREA OF THUNDERSTORMS IS MOVING TO THE NORTHEAST AT 30 MPH.

TANNER
Special weather statement, Apr 26, 5:46 PM CST, 2 hours 15 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
540 PM CST SAT APR 26 1986

AT 530 PM CST...NUMEROUS INTENSE THUNDERSTORMS CONTINUED OVER
SOUTHEAST SOUTH DAKOTA. THE STORMS WERE ALONG AND EAST OF THE
JAMES RIVER AND SOUTH OF A LINE FROM MITCHELL TO BROOKINGS.

LARGE HAIL AND STRONG WIND IS LIKELY IN THE AREA ALONG AND SOUTH
OF A LINE FROM MITCHELL TO SIOUX FALLS.

THESE STORMS WERE MOVING EAST AT 25 MILES AN HOUR.

ALSO...NUMEROUS SHOWERS AND THUNDERSTORMS...SOME WITH VERY HEAVY
RAIN...CONTINUED OVER CENTRAL AND NORTHEAST SOUTH DAKOTA...MAINLY
ALONG AND EAST OF THE MISSOURI RIVER AND NORTH OF A LINE FROM
BROOKINGS TO CHAMBERLAIN..WHICH IS= 60 MILES SOUTHEAST OF PIERRE.
VERY HEAVY RAIN IS LIKELY IN THE AREA ALONG AND 45 MILE EITHER
SIDE OF A LINE FROM PIERRE TO MOBRIDGE.

THESE SHOWERS AND THUNDERSTORMS WERE MOVING NORTH AT 40 MILES AN HOUR.

SPRINGER
Local storm report, Apr 26, 6:17 PM CST, 1 hour 44 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
615 PM CST SAT APR 26 1986

4:20 PM CST TYNDALL SD..UP TO BASEBALL SIZE HAIL.

5:20 PM CST VIBORG SD..TREE DOWN (BASE OF TREE 12 INCHES)

5:23 PM CSdT 2 MI WEST HURLEY SD TORNADO MOVING EAST NORTHEAST 30 MPH.

5:35 PM CST DAVIS SD..FUNNEL CLOUD.

5:35 PM CST CENTERVILLE SD..FUNNEL CLOUD.

BIER
Special weather statement, Apr 26, 6:48 PM CST, 1 hour 13 minutes before
SPECIA KHON 270048

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
645 PM CST SAT APR 26 1986

AT 630 PM CST...NUMEROUS INTENSE THUNDERSTORMS CONTINUED OVER PARTS
OF CENTRAL AND SOUTHEAST SOUTH DAKOTA.

THE STORMS WERE LOCATED EAST OF A WATERTOWN/YANKTON LINE..AND ALSO
NORTH OF A PIERRE/HURON LINE.

LARGE HAIL AND STRONG WINDS ARE LIKELY IN AND AROUND THESE STORMS.

THESE STORMS WERE MOVING EAST AT 25 MILES AN HOUR.

SPRINGER/MILLER
Special weather statement, Apr 26, 7:40 PM CST, 21 minutes before
SPECIA KHON 270140

SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE HURON SD
740 PM CST SAT APR 26 1986

AT 730 PM CST...NUMEROUS INTENSE THUNDERSTORMS CONTINUED OVER PARTS
OF CENTRAL SOUTH DAKOTA.

THE STORMS WERE LOCATED NORTH OF A PIERRE/MITCHELL LINE. MOSTLY LIGHT
SHOWERS WHERE LOCATED ALONG THE SOUTHEAST PART OF SOUTH DAKOTA.

HAIL AND STRONG WINDS ARE LIKELY IN AND AROUND THESE STORMS.

THE INTENSE THUNDERSTORMS THAT HAD BEEN LOCATED OVER PARTS OF EASTERN
SOUTH DAKOTA HAVE MOVED EASTWARD INTO SOUTHWEST MINNESOTA AND NORTHWEST
IOWA.

THESE STORMS WERE MOVING NORTHEAST AT 40 MILES AN HOUR.

SPRINGER/MILLER

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 26, 6:23 PM CSTSevere Thunderstorm WarningFSDLyon, Sioux67 min
Apr 26, 6:38 PM CSTTornado WarningFSDLyon, Osceola37 min
Apr 26, 6:46 PM CSTTornado WarningFSDLyon, Osceola29 min
Apr 26, 6:55 PM CSTTornado WarningFSDLyon, Osceola35 min
Apr 26, 7:58 PM CSTSevere Thunderstorm WarningFSDOsceola62 min

Nearby

Severe Thunderstorm Warnings in Iowa, 1986Every severe thunderstorm warning in 1986

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.