Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 21, NWS Duluth, MN

July 17, 1987Lake County, Saint Louis County, Minnesota

NWS Duluth, MN issued this severe thunderstorm warning at Jul 17, 1987, 4:37 PM CDT for Lake County, Saint Louis County, Minnesota. It was in force for 83 min.

The area

The counties it named.

The facts

Issued
Jul 17, 1987, 4:37 PM CDT (21:37 UTC)
Expired
Jul 17, 1987, 6:00 PM CDT
In force
83 min
Issued by
NWS Duluth, MN
Area
Whole counties

Counties Lake County, MN, Saint Louis 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

International Fa, MN (KINL), launched 12:00Z, 9.6 hours before the alert went out and 152 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, International Fa, MN at 12:00Z on 1987-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2239 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, International Fa, MN at 12:00Z on 1987-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -63 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
2239 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
-63 m²/s²
0-3 km storm-relative helicity
-13 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 KDLH 172137
SVRDLH
MNC075-137-172300-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DULUTH MN
437 PM CDT FRI JUL 17 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 600 PM CDT FOR PEOPLE IN THE FOLLOWING 
COUNTIES OF

NORTHEAST MINNESOTA...CENTRAL LAKE AND EAST CENTRAL ST. LOUIS


AT 435 PM CDT A SEVERE THUNDERSTORM WAS LOCATED BETWEEN AORORA
AND TIOMI MINNESOTA 20 MILES EAST OF VIRGINIA AND 40 MILES NORTH-
NORTHEAST OF DULUTH MINNESOTA AND MOVING NORTHEAST AT 30 MILES
AN HOUR. LOCATIONS IN THE PATH OF THIS SEVERE THUNDERSTORM DURING
THE NEXT HOUR AND A HALF..TILL 6PM CDT..INCLUDE SKIBO..BABBITT AND
ISABELLA MINNESOTA.
LARGE HAIL IS INDICATED WITH THIS SEVERE THUNDERSTORM.

REMEMBER SEVERE THUNDERSTORMS PRODUCE STRONG DAMAGING WINDS..LARGE
HAIL AND FREQUENT LIGHTNING STRIKES. 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.
THIS IS A DANGEROUS STORM SITUATION.  ACT QUICKLY.  IF YOU ARE IN
THE PATH OF A TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE._
OTHERWISE..GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR POSSIBLE.
AVOID WINDOWS.  ABANDON MOBILE HOMES FOR A REINFORCED BUILDING OR
GET INTO A DITCH OR CULVERT.

OLSON

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.