Alert archive / Minnesota / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 5, NWS Twin Cities, MN

April 29, 1991Le Sueur County, Rice County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 29, 1991, 4:47 PM CDT for Le Sueur County, Rice County, Minnesota. It was in force for 28 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
Apr 29, 1991, 4:47 PM CDT (21:47 UTC)
Expired
Apr 29, 1991, 5:15 PM CDT
In force
28 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Le Sueur County, MN, Rice County, MN

What was reported inside it

TimeReportWhereRemark
Apr 29, 4:50 PM CDTTornado F1Le Sueur, MN

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

Minneapolis, MN (KSTC), launched 12:00Z, 9.8 hours before the alert went out and 55 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, Minneapolis, MN at 12:00Z on 1991-04-29Temperature 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, Minneapolis, MN at 12:00Z on 1991-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 266 square meters per square second.1939587897Sfc1 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
562 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
266 m²/s²
0-3 km storm-relative helicity
267 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 KRST 292148 RRA
SVRRST
MNC079-131-292215-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ROCHESTER MN
447 PM CDT MON APR 29 1991
 
THE NATIONAL WEATHER SERVICE IN ROCHESTER MN HAS ISSUED A
SEVERE THUNDERSTORM WARNING     EFFECTIVE UNTIL  500 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATIONS...
 
IN SOUTH CENTRAL MINNESOTA
 
   ...LESUEUR COUNTY...RICE COUNTY
 
AT 4 40 PM RADAR INDICATED A PAIR OF SEVERE THUNDERSTORMS WERE LIKELY
OCCURRING NEAR CLEVELAND...15 MILES NORTHEAST OF MANKATO...AND NEAR THE
CITY OF FARIBAULT IN RICE COUNTY. MOVEMENT WAS NORTH AT 40 MILES AN
HOUR.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

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 29, 2:22 PM CDT, 2 hours 25 minutes before
WIZ006-292000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
215 PM CDT FRI APR 26 1991

...SEVERE THUNDERSTORM WATCH FOR A PART OF WEST CENTRAL WISCOMSIN UNTIL
...8 PM

A LINE OF STRONG THUNDERSTORMS WAS LOCATED IN EXTREME WEST CENTRAL
WISCONSIN EXTENDING FROM NEAR NEW RICHMOND..TO RIVER FALLS..TO
ELLSWORTH..TO PLUM CITY OR ABOUT 50 MILES WEST OF EAU CLAIRE.

THESE THUNDERSTORMS WERE MOVING RAPIDLY NORTH..NORTHEAST AT ABOUT 45 MPH
AND ARE CAPABLE OF PRODUCING WND GUSTS OF 50 TO 60 MPH VERY HEAVY RAIN
AND HAIL.

PERSONS IN EASTERN POLK..ST CROIX..PIERCE..AND ALL OF BARRON AND DUNN
COUNTY CAN EXPECT THIS THUNDERSTOM ACTIVITY BETWEEN 230 PM AND 3PM THIS
AFTERNOON.
RICHARDSON
Special weather statement, Apr 29, 2:28 PM CDT, 2 hours 19 minutes before
WIZ006-292000-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
215 PM CDT MON APR 29 1991

...SEVERE THUNDERSTORM WATCH FOR A PART OF WEST CENTRAL WISCOMSIN UNTIL
...8 PM

A LINE OF STRONG THUNDERSTORMS WAS LOCATED IN EXTREME WEST CENTRAL
WISCONSIN EXTENDING FROM NEAR NEW RICHMOND..TO RIVER FALLS..TO
ELLSWORTH..TO PLUM CITY OR ABOUT 50 MILES WEST OF EAU CLAIRE.

THESE THUNDERSTORMS WERE MOVING RAPIDLY NORTH..NORTHEAST AT ABOUT 45 MPH
AND ARE CAPABLE OF PRODUCING WND GUSTS OF 50 TO 60 MPH VERY HEAVY RAIN
AND HAIL.

PERSONS IN EASTERN POLK..ST CROIX..PIERCE..AND ALL OF BARRON AND DUNN
COUNTY CAN EXPECT THIS THUNDERSTOM ACTIVITY BETWEEN 230 PM AND 3PM THIS
AFTERNOON.
RICHARDSON
Special weather statement, Apr 29, 4:38 PM CDT, 9 minutes before
MNZ010-011-012-013-014-015-016-017-018-019-WIZ003-006-292230-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
435 PM CDT MON APR 29 1991

...SEVERE THUNDERSTORM WATCH IN EFFECT FOR MOST OF SOUTHERN
MINNESOTA AND WESTERN WISCONSIN UNTIL 800 PM CDT...

...STRONG THUNDERSTORMS APPROACHING TWIN CITIES METRO AREA...

STRONG THUNDERSTORMS OVER SOUTH CENTRAL MINNESOTA WERE MOVING
RAPIDLY NORTHWARD TOWARD THE GREATER TWIN CITIES METRO AREA
AT 430 PM.  THE STRONGEST STORMS WERE BETWEEN MANKATO AND OWATONNA.
THEY WERE PART OF A LARGER AREA OF THUNDERSTORMS MAINLY LOCATED
TO THE SOUTH OF A LINE FROM WORTHINGTON TO NEW ULM TO OWATONNA TO
ROCHESTER.  THESE STRONG STORMS HAVE PRODUCED DAMAGING WINDS
AND LARGE HAIL IN NORTHERN IOWA.

MOVEMENT WAS TO THE NORTH AT 40 TO 45 MILES AN HOUR AND SHOULD
APPROACH THE SOUTHERN FRINGE OF THE GREATER TWIN CITIES METRO
AREA OF SIBLEY...SCOTT...AND DAKOTA COUNTIES BY 500 PM.  BE PREPARED
TO SEEK SAFE SHELTER IF THREATENING WEATHER APPROACHES YOU.
CONTINUE TO MONITOR TV AND RADIO FOR LATER STATEMENTS AND
WARNINGS.
KRAFT

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 29, 3:58 PM CDTSevere Thunderstorm WarningMPXWatonwan32 min
Apr 29, 4:55 PM CDTSevere Thunderstorm WarningMPXScott, Sibley35 min
Apr 29, 4:55 PM CDTSevere Thunderstorm WarningMPXDakota35 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1991Every severe thunderstorm warning in 1991

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.