Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 105, NWS Twin Cities, MN

July 30, 1987Dakota County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 30, 1987, 12:57 AM CDT for Dakota County, Minnesota. It was in force for 13 min.

The area

The counties it named.

The facts

Issued
Jul 30, 1987, 12:57 AM CDT (05:57 UTC)
Expired
Jul 30, 1987, 1:10 AM CDT
In force
13 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

County Dakota 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, 6.0 hours before the alert went out and 47 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 1987-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3389 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 1987-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 38 square meters per square second.1939Sfc1 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
3389 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
1006 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
38 m²/s²
0-3 km storm-relative helicity
103 m²/s²
Significant tornado parameter
0.9
Supercell composite
5.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 300557
SVRMSP
MNC037-300700-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
1257 AM CDT THU JUL 30 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 200 AM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

SOUTHEAST MINNESOTA...
 SOUTHERN DAKOTA


AT 1250 AM A SEVERE THUNDERSTORM WAS LOCATED  OVER EAST CENTRAL
MINNESOTA 15 MILES SOUTH  OF DOWNTOWN ST PAUL NEAR APPLE VALLEY.

AT 1245 AM THE PUBLIC REPORTED TREES DOWN AND WINDS OF 60 TO 65
MILES AN HOUR IN THE APPLE VALLEY AREA.

THE STORM WAS MOVING SOUTHEAST AT 20 MILES AN HOUR AND WILL BE
AFEECTING THE CITIES OF FARMINGTON...HAMPTON AND VERMILLION.

REMEMBER SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60
MPH..DESTRUCTIVE HAIL..DEADLY LIGHTNING AND VERY HEAVY RAIN. ALSO
SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE A TORNADO WITH
LITTLE OR NO ADVANCE WARNING..SO BE_ ON THE LOOKOUT AND BE PREPARED
TO MOVE TO A PLACE OF SAFETY IF ONE IS SPOTTED.

RICHARDSON

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 29, 9:31 PM CDT, 3 hours 26 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
830 PM CDT WED JUL 29 1987

AT 825 PM CDT...STRONG THUNDERSTORMS HAD DEVELOPED OVER WEST CENTRAL
MINNESOTA ABOUT 20 MILES WEST OF WILLMAR ON THE SWIFT AND CHIPPEWA COUNTY
LINES.

THESE THUNDERSTORMS COULD PRODUCE SOME HEAVY DOWNPOURS AND STRONG GUSTY
WINDS AS THEY MOVE EAST AT ABOUT 10 TO 15 MILES AN HOUR.

NO SEVERE WEATHER HAS BEEN REPORTED WITH ThHESE STORMS BUT PERSONS IN
WEST CENTRAL MINNESOTA AND IN PARTICULAR SWIFT...CHIPPEWA AND KANDIYOHI
COUNTYS SHOULD BE ON THE LOOKOUT FOR THESE STORMS AND BE PREPARED TO SEEK
SAFE SHELTER IF THREATENING WEATHER DEVELOPS.
STANDFIELD
SWANBERG
Special weather statement, Jul 29, 9:49 PM CDT, 3 hours 8 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
930 PM CDT WED JUL 29 1987   ....CORRECTION FOR TIME....

AT 925 PM CDT...STRONG THUNDERSTORMS HAD DEVELOPED OVER WEST CENTRAL
MINNESOTA ABOUT 20 MILES WEST OF WILLMAR ON THE SWIFT AND CHIPPEWA COUNTY
LINES.

THESE THUNDERSTORMS COULD PRODUCE SOME HEAVY DOWNPOURS AND STRONG GUSTY
WINDS AS THEY MOVE EAST AT ABOUT 10 TO 15 MILES AN HOUR.

NO SEVERE WEATHER HAS BEEN REPORTED WITH THESE STORMS BUT PERSONS IN
WEST CENTRAL MINNESOTA AND IN PARTICULAR SWIFT...CHIPPEWA AND KANDIYOHI
COUNTYS SHOULD BE ON THE LOOKOUT FOR THESE STORMS AND BE PREPARED TO SEEK
SAFE SHELTER IF THREATENING WEATHER DEVELOPS.
ST|ANDFIELD
Special weather statement, Jul 29, 11:00 PM CDT, 1 hour 57 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1100 PM CDT WED JUL 29 1987

AT 1050 PM CDT...INTENSE THUNDERSTORMS CONTINUED TO DEVELOP OVER SOUTH
AND CENTRAL SECTIONS OF MINNESOTA FROM WEST OF ROCHESTER NORTHWEST TO
NEAR FAIRBAULT TO EAST OF LITCHFIELD TO NORTHWEST OF WILLMAR.

THE STRONGEST STORMS WERE LOCATED OVER KANDIYOHI...MEEKER...RICE AND
MC CLEOD COUNTYS.

VERY HEAVY RAINS...FREQUENT DANGEROUS LIGHTNING AND HAIL CAN BE EXPECTED
WITH THESE STORMS AS THEY MOVE SLOWLY EAST AT 10 TO 15 MILS AN HOUR.

NO SEVERE WEATHER HAS BEEN  REPORTED WITH THESE STORMS BUT PERSONS IN
THESE COUNTIES SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER AND BE
PREPARED TO SEEK SAFE SHELTER.
STANDFIELD
Special weather statement, Jul 30, 12:08 AM CDT, 49 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MINNEAPOLIS/ST PAUL MN
1205 PM CDT WED JUL 29 1987

...FLOOD WATCH FOR PORTIONS OF EAST CENTRAL AND CENTRAL MINNESOTA
INCLUDING THE TWIN CITIES METROPOLITAN AREA UNTIL 430 AM CDT THURSDAY
MORNING...

AT 1155 PM CDT...THUNDERSTORMS WERE PRODUCING VERY HEAVY RAINS IN A
BAND FROM EAST OF ROCHESTER NORTHWEST THROUGH THE SOUTHWEST SUBURBS
TO NORTHEAST OF WILLMAR.

THE STORMS WERE MOVING SLOWLY EAST AT 10 TO 15 MILES AN HOUR AND WITH
THIS SLOW MOVEMENT THE STORMS COULD ONCE AGAIN CAUSE FLOODING PROBLEMS
IN AREAS THAT HAVE HAD THE RECENT HEAVY RAINS.

PERSONS IN THE METRO AREA SHOULD BE ALERT TO POSSIBLE FLOODING AND BEF
PREPARED TO TAKE ACTION IF A FLOOD WARNING IS ISSUED.
STANDFIELD

Nearby

Severe Thunderstorm Warnings in Minnesota, 1987Every severe thunderstorm warning in 1987

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.