Alert archive / Minnesota / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 170, NWS Twin Cities, MN

August 17, 1986Steele County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 17, 1986, 1:50 AM CDT for Steele County, Minnesota. It was in force for 40 min.

The area

The counties it named.

The facts

Issued
Aug 17, 1986, 1:50 AM CDT (06:50 UTC)
Expired
Aug 17, 1986, 2:30 AM CDT
In force
40 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Steele 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, 6.8 hours before the alert went out and 97 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 1986-08-17Temperature 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 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 1986-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -91 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3000 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
-91 m²/s²
0-3 km storm-relative helicity
123 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 170650
SVRRST
MNC131-147-049-039-170730-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE ROCHESTER MN
150 AM CDT SUN AUG 17 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 230 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES OF

SOUTHEAST MINNESOTA...EASTERN RICE...NORTHERN STEELE...GOODHUE AND 
 NORTHERN DODGE

THIS WOULD INCLUDE TOWNS OF FARIBAULT..RED WING AND OWATONNA.
AT 135 AM CDT WEATHER RADAR INDICATED A STRONG LINE OF
THUNDERSTORMS FROM CANNON FALLS SOUTH TO WATERVILLE.
MOVEMENT WAS TO THE EAST AT 30 MPH.

 IF YOU ARE IN OR NEAR THE WARNED AREA GET TO A REINFORCED SHELTER
 AND PREPARE FOR STRONG DAMAGING WIND..LARGE HAIL..VERY HEAVY RAIN
 AND DANGEROUS LIGHTNING.

 REMEMBER THESE STORMS CAN AND OCCASIONALLY DO PRODUCE A TORNADO
 WITH LITTLE OR NO ADVANCE WARNING SO BE ON THE LOOKOUT.

  ANDERSON

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 16, 9:49 PM CDT, 4 hours 1 minute before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
940 PM CDT SAT AUG 16 1986

THE SEVERE THUNDERSTORMS OVER WESTCENTRAL WISCONSIN IN ST CROIX
COUNTY HAVE WEAKENED CONSIDERABLY SINCE ABOUT 920PM.  NO REPORTS OF
SEVERE WEATHER HAVE BEEN RECEIEVED SINCE AROUND 9PM WHEN GOLFBALL HAIL
FELL IN HOLTON OF EXTREME WESTERN ST CROIX COUNTY.  OTHER THUNDERSTORMS
REMAIN SCATTERED IN AN EAST TO WEST LINE FROM NEAR EAU CLAIR THROUGH
WAUSAU.

OTHER VERY STRONG THUNDERSTORMS WERE DEVELOPING AND MAKING FURTHER
INROADS INTO WESTERN MINNESOTA AND CENTRAL MINNESOTA.  THE AREA OF
STRONGEST STORMS WAS SCATTERED IN AN AREA FROM JUST NORTH OF MARSHALL IN
YELLOW MEDICINE COUNTY EAST TO AROUND GRANITE FALLS IN RENVELLE COUNTY
AND THEN INTO THE COSMOS..HECTOR AREA OF MEEKER AND RENVILLE COUNTIES.
THESE THUNDERSTORMS WILL MOVING INTO WRIGHT..MC LEOD AND SIBLEY COUNTIES
AFTER 10PM.

THESE STORMS WERE MOVING EAST TO }SOUTHEAST AT AROUND 20 MPH.
IF THREATENING WEATHER APPROACHES YOUR SEEK SHELTER AND IF SAFTEY
PERMITS RELAY SEVERE WEATHER REPORTS TO LOCAL LAW OFFICALS FOR
RELAY TO THE NATIONAL WEATHER SERVICE.
PAULSON
Special weather statement, Aug 16, 10:20 PM CDT, 3 hours 30 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1015 PM CDT SAT AUG 16 1986

VERY STRONG THUNDERSTORMS CONTINUED TO DEVELOP AND CONTINUE TO MAKE
PROGRESS ACROSS WESTERN AND INTO CENTRAL MINNESOTA.  THE LEADING EDGE
OF THESE THUNDERSTORMS WAS MOING INTO THE WESTERN TWIN CITY METRO AREA.
MARBLE HAIL WAS REPORTED IN DELANO OF SOUTHEAST WRIGHT COUNTY ABOUT 10
PM.  THIS THUNDERSTORM WAS MOVING INTO INTO THE INDEPENDENCE AREA OF
WESTERN HENNEPIN COUNTY AT 1015PM AND TRACK TOWARD THE PLYMOUTH AREA
OF HENNIPIN COUNTY AROUND 1030 PM IF IT MAINTAINS ITS STRENGTH.

OTHER STRONG THUNDERSTORMS REMAINED SCATTERED ACROSS MEEKER..RENVILLE
MC CLEOD..WRIGHT..AND KANDIYOHI COUNTIES. WHICH IS WEST OF THE TWIN
CITIES.  SOME OF CITIES AND TOWNS WHICH MAY BE NEAR THESE STRONGER
STORMS ARE OLIVIA..WILLMAR..AND LITCHFIELD.

THESE THUNDERSTORMS WERE MOVING EAST TO SOUTHEAST AT 20 MPH.
IF THREATENING WEATHER APPROACHES YOUR SEEK SHELTER AND IF SAFTEY
PERMITS RELAY SEVERE WEATHER REPORTS TO LOCAL LAW OFFICALS FOR
RELAY TO THE NATIONAL WEATHER SERVICE.
PAULSON
Local storm report, Aug 16, 10:45 PM CDT, 3 hours 5 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1045 PM CDT SAT AUG 9 1986

ATTN SELS A MSP

723 PM CDT  GOLF BALL SIZE HAIL NEAR CITY OF KNAPP OF DUNN COUNTY WI.

730 PM CDT  2 INCH HAIL IN BLOOMINGTON MN..S HENNEPIN COUNTY.
            (OFF DUTY NWS EMPLOYEE)

740 PM TO 800 PM CDT...INTERMITENT GOLF BALL SIZE HAIL AT MSP
                       AIRPORT.

742 PM CDT  52 MPH WIND GUST AT MSP.

815 PM CDT  GOLF BALL SIZE HAIL AT MAPLEWOOD MN OF RAMSEY COUNTY.

825 PM CDT  GOLF BALL SIZE HAIL AT OAKDALE MN OF WASHINGTON COUNTY.
           ( REPORTED  BY SKYWARN SPOTTER)
849 PM CDT  3/4 INCH HAIL AT HOULTON WI OF ST. CROIX COUNTY. REPORTED
            BY SHERIFF DISPATCH.

RICHARDSON
Local storm report, Aug 16, 10:47 PM CDT, 3 hours 3 minutes before
STORM REPORT....CORRECTION FOR DATE
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1045 PM CDT SAT AUG 16 1986

ATTN SELS A MSP

723 PM CDT  GOLF BALL SIZE HAIL NEAR CITY OF KNAPP OF DUNN COUNTY WI.

730 PM CDT  2 INCH HAIL IN BLOOMINGTON MN..S HENNEPIN COUNTY.
            (OFF DUTY NWS EMPLOYEE)

740 PM TO 800 PM CDT...INTERMITENT GOLF BALL SIZE HAIL AT MSP
                       AIRPORT.

742 PM CDT  52 MPH WIND GUST AT MSP.

815 PM CDT  GOLF BALL SIZE HAIL AT MAPLEWOOD MN OF RAMSEY COUNTY.

825 PM CDT  GOLF BALL SIZE HAIL AT OAKDALE MN OF WASHINGTON COUNTY.
           ( REPORTED  BY SKYWARN SPOTTER)
849 PM CDT  3/4 INCH HAIL AT HOULTON WI OF ST. CROIX COUNTY. REPORTED
            BY SHERIFF DISPATCH.

RICHARDSON
Special weather statement, Aug 17, 12:46 AM CDT, 1 hour 4 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1245 AM CDT SUN AUG 17 1986

AT 12.30 AM CDT...SHOWERS AND THUNDERSTORMS..SOME WITH HEAVY RAINS AND
HAIL..AND OCCASIONAL WIND GUSTS TO NEAR 50 MILES AN HOUR..WERE OCCURRING
OVER A LARGE PART OF THE SOUTH THIRD OF MINNESOTA..INTO WEST CENTRAL
WISCONSIN..AND NORTHWEST IOWA.

HEAVIEST THUNDERSTORMS WERE ALONG A 10 TO 15 MILE WIDE AREA FROM 30
MILES NORTHEAST OF ST PAUL NEAR ST CROIX FALLS..ACROSS THE TWIN CITIES..
TO NEAR MANKATO.  THIS IS THE AREA MOST LIKELY TO HAVE THE HAIL AND
TURBULENT WEATHER CONDITIONS.

MOVEMENT WAS SOUTHEAST AT 15 TO 20 MILES AN HOUR.
NESLEY
RELAY TO THE NATIONAL WEATHER SERVICE.
PAULSON
Local storm report, Aug 17, 1:08 AM CDT, 42 minutes before
STORM REPORT
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
105 AM CDT SUN AUG 17 1986

ATTN SELS A MSP

1108 PM CDT    POWER LINES DOWN IN CITY OF OLIVIA MN RENVILLE COUNTY.

1117 PM CDT    3/4 INCH HAIL IN CITY OF BIRD ISLAND MN..RENVILLE COUNTY.

RICHARDSON

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 16, 7:47 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Ramsey28 min
Aug 16, 7:47 PM CDTSevere Thunderstorm WarningMPXWashington28 min
Aug 16, 8:22 PM CDTSevere Thunderstorm WarningMPXWashington38 min
Aug 16, 10:57 PM CDTSevere Thunderstorm WarningMPXRenville63 min
Aug 17, 1:07 AM CDTSevere Thunderstorm WarningMPXBlue Earth, Le Sueur, Nicollet33 min
Aug 17, 1:50 AM CDTSevere Thunderstorm WarningMPXDodge, Goodhue, Rice40 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 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.