Alert archive / Michigan / Tornado Warnings in 1987

Tornado Warning 5, NWS Marquette, MI

July 20, 1987Delta County, Dickinson County, Menominee County, Michigan

NWS Marquette, MI issued this tornado warning at Jul 20, 1987, 2:18 PM EDT for Delta County, Dickinson County, Menominee County, Michigan. It was in force for 57 min. 2 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Jul 20, 1987, 2:18 PM EDT (18:18 UTC)
Expired
Jul 20, 1987, 3:15 PM EDT
In force
57 min
Issued by
NWS Marquette, MI
Area
Whole counties

Counties Delta County, MI, Dickinson County, MI, Menominee County, MI

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Jul 20, 2:55 PM EDTThunderstorm Wind 0Dickinson, MI
Jul 20, 3:10 PM EDTThunderstorm Wind 0Delta, MI

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 6.3 hours before the alert went out and 154 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, Green Bay/Straub, WI at 12:00Z on 1987-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3840 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, Green Bay/Straub, WI at 12:00Z on 1987-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 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
3840 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
653 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
73 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 KMQT 201818
TORMQT
MIC043-109-041-201915-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE MARQUETTE MI
218 PM EDT MON JUL 20 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 315 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

SOUTH CENTRAL UPPER MICHIGAN...SOUTHERN DICKINSON...NORTHERN 
 MENOMINEE AND SOUTHERN DELTA

AT 215 PM EDT...A TORNADO WAS REPORTED BY THE POLICE
10 MILES WEST OF IRON MOUNTAIN MICHIGAN...MOVING
EAST AT 40 MILES AN HOUR.

IF YOU ARE IN THE PATH OF THIS TORNADO...GO TO A BASEMENT SHELTER
IF AVAILABLE...OTHERWISE TO A CENTRAL INTERIOR ROOM ON THE LOWEST
FLOOR.  ABANDON CARS AND MOBILE HOMES FOR A REINFORCED BUILDING.

IF YOU ARE IN AN AREA THREATENED BY THE STORM..GO TO A REINFORCED
SHELTER AND PREPARE FOR DAMAGING WIND...LARGE HAIL...VERY HEAVY
RAIN AND LIGHTNING.

TE

What forecasters said that day

The local office's own words before this tornado 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 20, 12:15 PM EDT, 2 hours 3 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MARQUETTE MI
1215 PM EDT MON JUL 20 1987

...SEVERE THUNDERSTORM WATCH FOR PARTS OF WEST AND CENTRAL UPPER
MICHIGAN UNTIL 5 PM EDT...

AT 1205PM EDT...A 15-MILE-WIDE LINE OF THUNDERSTORMS WAS MOVING
RAPIDLY EAST ACROSS WEST UPPER MICHIGAN AT ABOUT 40 MILES AN HOUR.
THE LEADING EDGE OF THIS LINE WAS ABOUT 25 MILES EAST OF IRONWOOD.

A RADIO STATION ON IRONWOOD REPORTED A 20 DEGREE TEMPERATURE DROP AS
THE THUNDERSTORMS PASSED WITH HEAVY RAIN AND GUSTY WINDS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN OR NEAR THE WATCH AREA.
ALSO...A SEVERE THUNDERSTORM PRODUCES WINDS IN EXCESS OF' 58 MPH AND/OR
HAIL OF 3/4 INCH OR GREATER.

TE
Special weather statement, Jul 20, 12:34 PM EDT, 1 hour 44 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MARQUETTE MI
1233 PM EDT MON JUL 20 1987

...SEVERE THUNDERSTORM WATCH FOR PARTS OF WEST AND CENTRAL UPPER
MICHIGAN UNTIL 5 PM EDT...

AT 1230PM EDT...A 25-MILE-WIDE AREA OF THUNDERSTORMS WAS MOVING
RAPIDLY EAST ACROSS WEST UPPER MICHIGAN AT ABOUT 40 MILES AN HOUR.
THE LEADING EDGE OF THIS LINE WAS ABOUT 40 MILES EAST OF IRONWOOD
AND 15 MILES WEST OF HOUGHTON.

NO SEVERE WEATHER HAS BEEN REPORTED WITH THESE THUNDERSTORMS IN UPPER
MICHIGAN...YET.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS THAT CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN OR NEAR THE WATCH AREA.
ALSO...A SEVERE THUNDERSTORM PRODUCES WINDS IN EXCESS OF 58 MPH ANDK/OR
HAIL OF 3/4 INCH OR LARGER IN DIAMETER.
TE
Special weather statement, Jul 20, 1:34 PM EDT, 44 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE MARQUETTE MI
135 PM EDT MON JUL 20 1987

AT 130 PM EDT A STRONG THUNDERSTORM WAS NEAR GREEN BAY WISCONSON.
OTHER THUNDERSTORMS WERE FROSM LANSE MICHIGAN THROUGH IRON RIVER MICHIGAN
TO NEAR WAUSAU WISCONSIN.

ALL THE THUNDERSTORMS WERE MOVING TO THE EAST SOUTHEAST AT 45 MILES
AN HOUR.

FK

The office that day

Everything else NWS Marquette, MI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 20, 2:02 PM EDTSevere Thunderstorm WarningMQTDickinson, Marquette, Menominee58 min
Jul 20, 2:02 PM EDTSevere Thunderstorm WarningMQTDelta58 min

Nearby

Tornado Warnings in Michigan, 1987Every tornado warning in 1987Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.