Alert archive / Michigan / Severe Thunderstorm Warnings in 1991

Severe Thunderstorm Warning 21, NWS Gaylord, MI

July 3, 1991Alpena County, Michigan

NWS Gaylord, MI issued this severe thunderstorm warning at Jul 3, 1991, 1:53 PM EDT for Alpena County, Michigan. It was in force for 67 min.

The area

The counties it named.

The facts

Issued
Jul 3, 1991, 1:53 PM EDT (17:53 UTC)
Expired
Jul 3, 1991, 3:00 PM EDT
In force
67 min
Issued by
NWS Gaylord, MI
Area
Whole counties

County Alpena County, MI

The nearest sounding before it

Sault Ste Marie, MI (KY62), launched 12:00Z, 5.9 hours before the alert went out and 169 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, Sault Ste Marie, MI at 12:00Z on 1991-07-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Sault Ste Marie, MI at 12:00Z on 1991-07-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 137 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
830 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
137 m²/s²
0-3 km storm-relative helicity
192 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 KAPN 031755 COR
SVRAPN
MIC007-031900-

BULLETIN - IMMEDIATE BROADCAST REQUESTED.. CORRECTION TO TIME
SEVERE THUNDERSTORM AND SPECIAL MARINE WARNING
NATIONAL WEATHER SERVICE ALPENA MI
153 PM EDT WED JUL 3 1991

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
AND SPECIAL MARINE WARNING EFFECTIVE UNTIL 300 PM EDT FOR
PEOPLE IN THE FOLLOWING COUNTY

   IN THE NORTHEAST PART OF LOWER MICHIGAN
      ALPENA

...THIS WARNING ALSO INCLUDES THE ADJACENT COASTAL WATERS FOR THE
COUNTY JUST MENTIONED

AT 150 PM A SEVERE THUNDERSTORM WAS MOVING INTO ALPENA COUNTY...
NEAR THE FLETCHER FLOODWATERS...OR 22 MILES WEST OF ALPENA.

THIS THUNDERSTORM WAS MOVING TO THE EAST AT 20 MILES AND HOUR AND
WILL BE MOVING JUST SOUTH OF LACHINE BY 215 PM...AND CLOSE TO
ALPENA BETWEEN 230 AND 245 PM.

IF YOU ARE SOUTH OF LACHINE OR AROUND ALPENA...BE PREPARED FOR
HAIL...DAMAGING WINDS...AND VERY HEAVY RAIN.

REMEMBER...SEVERE THUNDERSTORMS CAN AND SOMETIMES DO PRODUCE TORNADOES
WITH LITTLE OR NO ADVANCE WARNING...SO BE ON THE LOOKOUT.

CAMPBELL

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 1:39 PM EDTSevere Thunderstorm WarningAPXMontmorency21 min

Nearby

Severe Thunderstorm Warnings in Michigan, 1991Every 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.