Alert archive / Minnesota / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 4, NWS Twin Cities, MN

April 29, 1991Watonwan County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Apr 29, 1991, 3:58 PM CDT for Watonwan County, Minnesota. It was in force for 32 min.

The area

The counties it named.

The facts

Issued
Apr 29, 1991, 3:58 PM CDT (20:58 UTC)
Expired
Apr 29, 1991, 4:30 PM CDT
In force
32 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Watonwan County, MN

The nearest sounding before it

Minneapolis, MN (KSTC), launched 12:00Z, 9.0 hours before the alert went out and 126 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 292059
SVRRST
MNC165-292130-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ROCHESTER MN
358 PM CDT MON APR 29 1991
 
THE NATIONAL WEATHER SERVICE IN ROCHESTER MN HAS ISSUED A
SEVERE THUNDERSTORM WARNING     EFFECTIVE UNTIL  430 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN SOUTH CENTRAL MINNESOTA
 
   ...WESTERN WATONWAN COUNTY
 
AT 3 50 PM RADAR INDICATED THAT A SEVERE THUNDERSTORM WAS LIKELY
OCCURING NEAR FOX LAKE...10 MILE WEST OF FAIRMONT. MARTIN COUNTY SHERIFF
ALSO REPORTED MARBLE SIZE HAIL WITH THIS STORM NEAR SHERBORN AT 3 45 PM.
THE STORM WAS MOVING NORTH AT 40 MILE AN HOUR.
 
 
WHEN THUNDERSTORMS ARE OCCURRING..MOVE INSIDE A STRONG BUILDING
DO NOT STAND BY WINDOWS.  DON'T USE TELEPHONES OR ELECTRICAL
APPLIANCES UNLESS IN AN EMERGENCY. REMEMBER SEVERE THUNDERSTORMS
CAN AND OCCASIONALLY DO PRODUCE TORNADOS WITH LITTLE OR NO WARNING.

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, 1 hour 36 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, 1 hour 30 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

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 4:47 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Rice28 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; the sounding from the Mesonet's radiosonde archive.