Alert archive / Minnesota / Severe Thunderstorm Warnings in 1989

Severe Thunderstorm Warning 83, NWS Twin Cities, MN

August 21, 1989Hennepin County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 21, 1989, 9:06 PM CDT for Hennepin County, Minnesota. It was in force for 69 min.

The area

The counties it named.

The facts

Issued
Aug 21, 1989, 9:06 PM CDT (02:06 UTC)
Expired
Aug 21, 1989, 10:15 PM CDT
In force
69 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Hennepin County, MN

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

Minneapolis, MN (KSTC), launched 00:00Z, 2.1 hours before the alert went out and 20 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 00:00Z on 1989-08-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2042 joules per kilogram.LCLEL10008507005003002001001 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 00:00Z on 1989-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 87 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
2042 J/kg
Mixed-layer CIN
0 J/kg
Mixed-layer LCL
982 m above ground
0-6 km bulk shear
40 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
165 m²/s²
Significant tornado parameter
1.3
Supercell composite
7.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 220207
SVRMSP
MNC053-220315-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
906 PM CDT MON AUG 21 1989
 
THE NATIONAL WEATHER SERVICE IN MINNEAPOLIS HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1015 PM CDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN EAST CENTRAL MINNESOTA
          ...HENNEPIN
 
RADAR AND SURFACE WIND REPORTS INDICATE A SEVERE THUNDERSTORM ENTERING
WESTERN HENNIPEN COUNTY. THE STORM IS MOVING EAST AT 20 MPH
AND SHOULD PASS DOWNTOWN MINNEAPOLIS AT ABOUT 930 PM CDT THIS EVENING.
 
SURFACE WIND ESTIMATES OF 50 TO 60 MPH HAVE BEEN RECEIVED BY TRAINED
OBSERVERS.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE. REMEMBER SEVERE THUNDERSTORMS
CAN AND OCCASIONALLY DO PRODUCE TORNADOES WITH LITTLE ADVANCE WARNING
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
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, Aug 21, 5:19 PM CDT, 3 hours 47 minutes before
SPECIAL WEATHER STATEMENT...CORRECTION FOR DATE AND TIME
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
518 PM CDT MON AUG 21 1989

...DANGEROUS SEVERE WEATHER SITUATION SETTING UP FOR SOUTH AND
   CENTRAL MINNESOTA THIS EVENING...
AFTER SEVERAL YEARS OF LOW SEVERE WEATHER FREQUENCY FOR MUCH OF
SOUTH MINNESOTA..A VERY ACTIVE EVENING APPEARS TO BE SHAPING UP
FOR MUCH OF THE AREA THIS MONDAY.

THE WEATHER SITUATION THIS EVENING IS FAVORABLE FOR BOTH SEVERE
THUNDERSTORM AND TORNADO FORMATION DUE TO A COMBINATION OF STRONG
DYNAMICS FOR THIS TIME OF YEAR..AND A GREAT DEAL OF AIRMASS
INSTABILITY.

IT IS IMPORTANT TO STAY ABREAST OF THE WEATHER SITUATION THIS
EVENING AS WEATHER CONDITIONS ARE LIKELY TO CHANGE QUITE RAPIDLY
AT ANY ONE SPOT AS THESE STORMS MOVE IN.

POWERFUL THUNDERSTORMS HAVE FORMED IN WEST CENTRAL MINNESOTA AND
THERE IS NO REASON THAT THEY WILL NOT HOLD TOGETHER AND
SWEEP ACROSS ALL OF SOUTH MINNESOTA BEFORE THE 5EVENING IS OVER.

THE TWIN CITIES IS LIKELY TO GET INTO THE ACTION AFTER ABOUT 8 PM
CDT THIS EVENING..BUT THE AIRMASS IS UNSTABLE ENOUGH FOR SEVERE
STORMS TO DEVELOP BEFORE THAT TIME.

TOGSTAD
Special weather statement, Aug 21, 7:10 PM CDT, 1 hour 56 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
709 PM CDT MON AUG 21 1989

...MARBLE SIZE HAIL IN EASTERN RENVILLE COUNTY...MOVING INTO MCLEOD
COUNTY...

AT 649 PM...ONE HALF INCH HAIL FELL IN HECTOR...OR ABOUT 20 MILES
NORTHEAST OF REDWOOD FALLS.  THE STORM HAS SINCE MOVED INTO
WESTERN MCLEOD COUNTY...BUT RADAR INDICATED THE STORM HAS NOT
INCREASED AT THIS POINT.

HOWEVER...PERSONS IN MCLEOD SHOULD BE READY TO GET TO SHELTER IF THE
STORM SHOULD SUDDENLY INCREASE.  LISTEN FOR LATER STATEMENTS AND
POSSIBLE WARNINGS.

KRAUSE
Special weather statement, Aug 21, 8:29 PM CDT, 37 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
830 PM CDT MON AUG 21 1989

...STRONG THUNDERSTORMS OVER MCLEOD COUNTY WILL BE ENTERING WESTERN
HENNEPIN COUNTY AROUND 9 PM CDT THIS EVENING...

STRONG THUNDERSTORMS WILL BE PASSING OVER LAKE MINNETONKA BETWEEN
9 PM CDT AND 10 PM CDT. THESE STORMS HAVE A HISTORY OF PRODUCING
30 TO 45 MPH WINDS AND BLINDING RAINFALL SO RECREATIONAL BOATERS
SHOULD GET OFF THE LAKE IMMEDIATELY!s

TOGSTAD
Special weather statement, Aug 21, 8:33 PM CDT, 33 minutes before
URBAN AND SMALL STREAM FLOOD STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
830 PM CDT MON AUG 21 1989

...THUNDERSTORMS WITH HEAVY RAINFALL APPROACHING THE TWIN CITIES
   METROPOLITAN AREA...

A LINE OF THUNDERSTORMS WITH TORRENTIAL RAINFALL HAS BEEN SAGGING
SLOWLY SOUTH THROUGH EAST CENTRAL MINNESOTA TOWARD THE TWIN CITIES
METROPOLITAN AREA. AT 830 PM THIS LINE OF THUNDERSTORMS EXTENDED FROM
HUTCHINSON IN NORTHERN MCLEOD COUNTY THROUGH CENTRAL WRIGHT COUNTY TO
THE ELK RIVER AREA ALONG THE MISSISSIPPI RIVER AND ON NORTH TO CAMBRIDGE
IN ISANTI COUNTY.

HEAVY RAINFALL RESULTING FROM THIS LINE OF THUNDERSTORMS IS LIKELY TO
CAUSE LOW LAND FLOODING AND POSSIBLY RAPID RUNOFF IN NORTH AND NORTHWEST
OF THE TWIN CITIES THROUGH PORTIONS OF WRIGHT..SHERBURNE AND ISANTI
COUNTIES. RUNOFF FROM THE HEAVY RAIN HAS ACCUMULATED TO 6 TO 8 INCHES
AT HIGHWAY INTERSECTIONS IN THE VICINITY OF HOWARD LAKE IN WRIGHT
COUNTY.

THIS LINE OF THUNDERSTORMS MAY ALSO CAUSE FLOODING IN FLOOD PRONE AREAS
SUCH AS UNDERPASSES AS IS MOVES INTO THE METROPOLITAN AREA THIS
EVENING. THIS LINE OF THUNDERSTORMS IS MOVING SOUTHEAST AROUND
15 MILES PER HOUR AND WILL BEGIN TO MOVE INTO WESTERN CARVER...
NORTHERN AND WESTERN HENNEPIN AND ANOKA COUNTIES SHORTLY AFTER
900PM. BY BETWEEN 1000 AND 1030 PM THE THUNDERSTORMS WILL BE
MOVING INTO DOWNTOWN MINNEAPOLIS AND ST PAUL AND THEN INTO THE
SOUTHERN SECTIONS OF THE METRO AREA AFTER 1100PM.
WJH
Special weather statement, Aug 21, 8:45 PM CDT, 21 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
845 PM CDT MON AUG 21 1989

...STRONG THUNDERSTORMS OVER WRIGHT COUNTY WILL BE ENTERING WESTERN
HENNEPIN COUNTY AROUND 9 PM CDT THIS EVENING...

STRONG THUNDERSTORMS WILL BE PASSING OVER WESTERN HENNIPEN COUNTY
9 PM CDT AND 10 PM CDT. SPOTTERS NOW REPORT 50 MPH WINDS AT MONTROSE
IN SOUTHEAST WRIGHT COUNTY. ALL RECREATIONAL INTERESTS IN WEST
HENNIPEN COUNTY SHOULD SEEK SHELTER IMMEDIATELY..BOATERS..GET OFF
AREA LAKE QUICKLY!

TOGSTAD
Special weather statement, Aug 21, 8:47 PM CDT, 19 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
845 PM CDT MON AUG 21 1989

...STRONG THUNDERSTORMS OVER WRIGHT COUNTY WILL BE ENTERING WESTERN
HENNEPIN COUNTY AROUND 9 PM CDT THIS EVENING...

STRONG THUNDERSTORMS WILL BE PASSING OVER WESTERN HENNEPIN COUNTY
9 PM CDT AND 10 PM CDT. SPOTTERS NOW REPORT 50 MPH WINDS AT MONTROSE
IN SOUTHEAST WRIGHT COUNTY. ALL RECREATIONAL INTERESTS IN WEST
HENNEPIN COUNTY SHOULD SEEK SHELTER IMMEDIATELY..BOATERS..GET OFF
AREA LAKES QUICKLY!

TOGSTAD

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 7:09 PM CDTSevere Thunderstorm WarningMPXMeeker36 min
Aug 21, 7:48 PM CDTSevere Thunderstorm WarningMPXAnoka, Chisago57 min
Aug 21, 8:02 PM CDTSevere Thunderstorm WarningMPXLac qui Parle58 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1989Every severe thunderstorm warning in 1989

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.