Alert archive / Michigan / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 21, NWS Marquette, MI

August 29, 1991Ontonagon County, Michigan

NWS Marquette, MI issued this severe thunderstorm warning at Aug 29, 1991, 10:12 PM EDT for Ontonagon County, Michigan. It was in force for 48 min.

The area

The counties it named.

The facts

Issued: Aug 29, 1991, 10:12 PM EDT (02:12 UTC)
Expired: Aug 29, 1991, 11:00 PM EDT
In force: 48 min
Issued by: NWS Marquette, MI
Area: Whole counties

County Ontonagon County, MI

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 2.2 hours before the alert went out and 272 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 833 J/kg
Mixed-layer CIN: -67 J/kg
Mixed-layer LCL: 1362 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 31 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 300212
SVRMQT
MIC131-300315-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MARQUETTE MI
1012 PM EDT THU AUG 29 1991
 
THE NATIONAL WEATHER SERVICE IN MARQUETTE HAS ISSUED A
SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 1115 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION...
 
IN WEST UPPER MICHIGAN
 
   ...WEST CENTRAL ONTONAGON COUNTY
 
AT 10 05 PM EDT...A SEVERE THUNDERSTORM HAD DEVELOPED OVER WESTERN
ONTONAGON COUNTY. THIS STORM WAS 25 MILES NORTHEAST OF IRONWOOD MICHIGAN
AND WAS MOVING EAST AT 20 MILES AN HOUR.
 
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN.
FOR YOUR PROTECTI4ON MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS.  HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.
 
DG

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 29, 9:21 PM EDT, 51 minutes before

MIZ076>79-300200-

SPECIAL WEATHER STATEMENT AND SHORT RANGE WEATHER SUMMARY
NATIONAL WEATHER SERVICE MARQUETTE MI
900 PM EDT SUN AUG 25 1991

...STRONG THUNDERSTORMS MOVING INTO WESTERN UPPER MICHIGAN
AND WESTERN LAKE SUPERIOR...

AT 950 PM EDT...A LINE OF STRONG THUNDERSTORMS WITH VERY HEAVY RAIN...
FREQUENT LIGHTNING AND GUSTY WINDS WHICH HAD DEVELEDOPED JUST AHEAD OF
A COLD FRONT IN NORTHEAST WISCONSIN...WAS MOVING INTO EXTREME WESTERN
UPPER MICHIGAN.  THE LEADING EDGE OF THESE STORMS WAS IN THE IRONWOOD
MICHIGAN.

THESE STORMS WERE MOVING EAST AT 25 MILES AN HOUR AND WILL CONTINUE
TO MOVE EAST INTO WEST END OF UPPER MICHIGAN.  THESE STORMS WILL BEGIN TO
MOVE THROUGH THE IRONWOOD AREA BY 9 45 PM EDT.

PERSONS IN GOGEBIC...ONTONAGON...HOUGHTON...AND IRON COUNTIES OF EXTREME
WESTERN UPPER MICHIGAN SHOULD BE PREPARED TO TAKE SHELTER AS THESE STORMS
APPROACH YOUR AREA.

STAY TUNED TO NATIONAL WEATHER SERVICE RADIO FOR FURTHER UPDATES AND
STATEMENTS ON THIS WEATHER SITUATION.

DG

Nearby

Severe Thunderstorm Warnings in Michigan, 1991 Every severe thunderstorm warning in 1991

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.