Alert archive / Minnesota / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 99, NWS Twin Cities, MN

July 17, 1991Stearns County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 17, 1991, 1:34 PM CDT for Stearns County, Minnesota. It was in force for 56 min.

The area

The counties it named.

The facts

Issued
Jul 17, 1991, 1:34 PM CDT (18:34 UTC)
Expired
Jul 17, 1991, 2:30 PM CDT
In force
56 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Stearns County, MN

The nearest sounding before it

Minneapolis, MN (KSTC), launched 12:00Z, 6.6 hours before the alert went out and 111 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 1991-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2574 joules per kilogram.LCLLFCEL10008507005003002001001 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 1991-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 square meters per square second.193958Sfc1 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
2574 J/kg
Mixed-layer CIN
-125 J/kg
Mixed-layer LCL
983 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
69 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KSTC 171834
SVRSTC
MNC145-171930-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ST CLOUD MINNESOTA
134 PM CDT WED JUL 17 1991
 
THE NATIONAL WEATHER SERVICE IN ST CLOUD MINNESOTA   HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL  230 PM CDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN CENTRAL MINNESOTA
 
   ...EASTERN STEARNS COUNTY
 
AT 1 30 PM CDT RADAR INDICATED A THUNDERSTORM ENTERING STEARNS COUNTY
25 MILES NORTHWEST OF ST. CLOUD. THIS THUNDERSTORM COULD CONTAIN LARGE
HAIL...VERY HEAVY RAIN...AND FREQUENT LIGHTNING STRIKES. THIS
THUNDERSTORM WAS MOVING SOUTHEAST AT 20 MPH.
 
SOME TOWNS IN THE PATH OF THIS THUNDERSTORM ARE
HOLDINGFORD...ALBANY...AVON...AND ST. CLOUD. THIS THUNDERSTORM WILL
MOVE THROUGH THESE TOWNS BY 2 30 PM CDT.
 
WHEN THUNDERSTORMS ARE OCCURRING...PEOPLE SHOULD MOVE INSIDE A
STRONG BUILDING.  DO NOT STAND BY WINDOWS.  DON'T USE TELEPHONES
OR ELECTRICAL APPLIANCES UNwLESS IN AN EMERGENCY UNTIL THE STORM
HAS PASSED.  MOTORISTS SHOULD NOT DRIVE INTO LOW WATER CROSSINGS.
 
NNNN

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, Jul 17, 12:30 PM CDT, 1 hour 4 minutes before
MNZ014-011-171830-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST CLOUD MINNESOTA
1230 PM CDT WED JUL 17 1991

...SEVERE THUNDERSTORM WATCH THIS WEDNESDAY AFTERNOON AND EVENING
UNTIL 7 PM CDT...

AT 1228 PM CDT THUNDERSTORMS WERE SCATTERED ACROSS CENTRAL MINNESOTA.
THE THUNDERSTORMS WERE LOCATED AT ALEXANDRIA AND EXTENDED SOUTHEAST
TO COKATO...32 MILES SOUTH OF ST CLOUD.

THE THUNDERSTORMS WERE MOVING EAST AT 20 TO 25 MPH AND WILL MOVE
THROUGH THE COMMUNITIES OF ROUND PRAIRIE...RICHMOND AND PAYNESVILLE
BETWEEN 1235 AND 1245 PM CDT.

THE THUNDERSTORMS WILL HAVE HEAVY RAINFALLS...SMALL HAIL AND DEADLY
CLOUD TO GROUND LIGHTNING. PLEASE MOVE INDOORS TO SAFE SHELTER IF THE
THUNDERSTORMS APPROACH YOUR AREA.

NNNN
Special weather statement, Jul 17, 12:55 PM CDT, 39 minutes before
MNZ004-005-008-009-011-170500-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1255 PM CDT WED JUL 17 1991

...SEVERE THUNDERSTORM WATCH 686 UNTIL 700 PM...INCLUDES TWIN CITIES...
...TORRENTIAL RAINS AND STREET FLOODING LIKELY AROUND THE TWIN CITIES...

AT 1245 AM...THUNNDERSTORMS WITH VERY HEAVY TO TORRENTIAL RAINFALL AND SMALL
HAIL WERE SPREAD ACROSS THE TWIN CITIES...STREET FLOODING IS LIKELY FROM THESE
THUNDERSTORMS...ESPECIALLY AROUND THE NORTHEERN HALF OF THE TWIN CITIES.

OTHERWISE A BAND OF SHOWERS AND THUNDERSTORMS 50 MILES WIDE WAS DETECTED FROM
EASTERN NORTH DAKOTA ACROSS CENTRAL MINNESOTA...THROUGH THE TWIN CITIES...OVER
THROUGH PARTS OF WEST AND WEST CENTRAL WISCONSIN.

THE THUNDERSTORMS WITH THE HEAVIEST SHOWERS AND SMALL HAIL WERE LOCATED BETWEEN
ALEAXNDRIA AND LITTLE FALLS AROUND LONG PRAIRIE IN CENTRAL MINNESOTA...AND NEAR
1-694...FROM CORCORAN AND MAPLE GROVE OVER TO ROSEVILLE AND NORTH ST PAUL IN
THE TWIN CITIES AND...FROM HUDSON SOUTHEAST TO ELLSWORTH AND DURAND IN WESTERN
WISCONSIN.

MOVEMENT WAS TO THE EAST AT 20 MILES AN HOUR.

AS OF 1250 PM...NO SEVERE THUNDERSTORM WARNINGS WERE IN EFFECT...THE MAJOR
THREAT AT THIS POINT IS THE DANGEROUS LIGHTNING AND POSSIBILITY OF STREET
FLOODING ESPECIALLY AROUND THE TWIN CITIES.
Special weather statement, Jul 17, 12:58 PM CDT, 36 minutes before
MNZALL-171900-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1255 PM CDT WED JUL 17 1991

...SEVERE THUNDERSTORM WATCH 686 UNTIL 700 PM...INCLUDES TWIN CITIES...
...TORRENTIAL RAINS AND STREET FLOODING LIKELY AROUND THE TWIN CITIES...

AT 1245 AM...THUNNDERSTORMS WITH VERY HEAVY TO TORRENTIAL RAINFALL AND SMALL
HAIL WERE SPREAD ACROSS THE TWIN CITIES...STREET FLOODING IS LIKELY FROM THESE
THUNDERSTORMS...ESPECIALLY AROUND THE NORTHEERN HALF OF THE TWIN CITIES.

OTHERWISE A BAND OF SHOWERS AND THUNDERSTORMS 50 MILES WIDE WAS DETECTED FROM
EASTERN NORTH DAKOTA ACROSS CENTRAL MINNESOTA...THROUGH THE TWIN CITIES...OVER
THROUGH PARTS OF WEST AND WEST CENTRAL WISCONSIN.

THE THUNDERSTORMS WITH THE HEAVIEST SHOWERS AND SMALL HAIL WERE LOCATED BETWEEN
ALEAXNDRIA AND LITTLE FALLS AROUND LONG PRAIRIE IN CENTRAL MINNESOTA...AND NEAR
1-694...FROM CORCORAN AND MAPLE GROVE OVER TO ROSEVILLE AND NORTH ST PAUL IN
THE TWIN CITIES AND...FROM HUDSON SOUTHEAST TO ELLSWORTH AND DURAND IN WESTER
WISCONSIN.

MOVEMENT WAS TO THE EAST AT 20 MILES AN HOUR.

AS OF 1250 PM...NO SEVERE THUNDERSTORM WARNINGS WERE IN EFFECT...THE MAJOR
THREAT AT THIS POINT IS THE DANGEROUS  LIGHTNING AND POSSIBILITY OF STREET
FLOODING ESPECIALLY AROUND THE TWIN CITIES.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 2:02 PM CDTSevere Thunderstorm WarningMPXBenton58 min
Jul 17, 2:07 PM CDTSevere Thunderstorm WarningMPXAnoka, Chisago, Washington33 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.