Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 69, NWS Twin Cities, MN

July 23, 1987Anoka County, Isanti County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 23, 1987, 1:11 PM CDT for Anoka County, Isanti County, Minnesota. It was in force for 49 min.

The area

The counties it named.

The facts

Issued
Jul 23, 1987, 1:11 PM CDT (18:11 UTC)
Expired
Jul 23, 1987, 2:00 PM CDT
In force
49 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Anoka County, MN, Isanti 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 12:00Z, 6.2 hours before the alert went out and 68 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 1987-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 575 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 1987-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -16 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
575 J/kg
Mixed-layer CIN
-138 J/kg
Mixed-layer LCL
1013 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
-16 m²/s²
0-3 km storm-relative helicity
-25 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 231811
SVRMSP
MNC003-059-231900-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
111 PM CDT THU JUL 23 1987

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

EAST CENTRAL MINNESOTA...
 NORTHERN ANOKA AND SOUTHERN ISANTI


AT..107 PM CDT..RADAR WAS INDICATED A SEVERE THUNDERSTORM ACROSS
EASTERN SHERBURNE COUNTY FROM NEAR ZIMMERMAN TO PRINCETON FROM
30 TO 40 MILES NORTHWEST OF MINNEAPOLIS.

THIS SEVERE THUNDERSTORM WAS MOVING EAST SOUTHEAST AND WILL BE
AFFECTING AREAS NEAR..ISANTI..CAMBRIDGE..ST FRANCIS AND ANOKA.

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.

WILLIS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 23, 12:15 PM CDTSevere Thunderstorm WarningMPXBenton, Sherburne, Stearns60 min
Jul 23, 12:15 PM CDTSevere Thunderstorm WarningMPXMille Lacs60 min
Jul 23, 2:08 PM CDTSevere Thunderstorm WarningMPXWashington52 min
Jul 23, 5:15 PM CDTSevere Thunderstorm WarningMPXSherburne60 min
Jul 23, 5:33 PM CDTSevere Thunderstorm WarningMPXWright42 min
Jul 23, 6:16 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin, Wright59 min
Jul 23, 6:40 PM CDTTornado WarningMPXAnoka, Hennepin65 min

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.