Alert archive / Michigan / Severe Thunderstorm Warnings in 1986

Severe Thunderstorm Warning 13, NWS Detroit, MI

May 17, 1986Washtenaw County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at May 17, 1986, 3:46 PM EDT for Washtenaw County, Michigan. It was in force for 44 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: May 17, 1986, 3:46 PM EDT (19:46 UTC)
Expired: May 17, 1986, 4:30 PM EDT
In force: 44 min
Issued by: NWS Detroit, MI
Area: Whole counties

County Washtenaw 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

Time	Report	Where	Remark
May 17, 3:55 PM EDT	Hail 1	Washtenaw, MI
May 17, 4:20 PM EDT	Hail 1	Washtenaw, 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

Detroit, MI (KFNT), launched 12:00Z, 7.8 hours before the alert went out and 62 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1271 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 28 m²/s²
0-3 km storm-relative helicity: 62 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 KDTW 171946
SVRDTW
MIC161-172030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DETROIT MI
346 PM EDT SAT MAY 17 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM 
WARNING EFFECTIVE UNTIL 430 PM EDT FOR PEOPLE IN THE FOLLOWING 
COUNTY OF

SOUTHEAST LOWER MICHIGAN...WASHTENAW

THE SEVERE THUNDERSTORM WARNING FOR WASHTENAW COUNTY IS EXTENDED
TILL 430 PM AS MARBLE TO GOLF SIZE HAIL CONTINUE TO BE REPORTED
BETWEEN MANCHESTER AND ANN ARBOR AT 340 PM EDT.

REMEMBER SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS..LARGE HAIL..
DEADLY LIGHTNING AND HEAVY RAIN THAT CAN QUICKLY FLOOD A LOW LYING
AREA.

 ..USE IF TORNADO WATCH IS IN EFFECT..BE SURE TO ERASE THIS LINE...
 THESE STORMS 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.

MARINO

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, May 17, 3:17 PM EDT, 29 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ANN ARBOR MI
310 PM EDT SAT MAY 17 1986

 ...TORNADO WATCH NUMBER 189 IS IN EFFECT UNTIL 900PM FOR PERSONS IN
    MUCH OF SOUTHERN LOWER MICHIGAN...

VERY HEAVY THUNDERSTORMS CONTINUE TO DEVELOP ACROSS SOUTHERN LOWER
MICHIGAN FROM JUST WEST OF DETROIT TO JUST SOUTH OF MUSKEGON.
MARBEL SIZED HAIL AND STRONG WINDS WERE REPORTED AT 230 PM IN SOUTHERN
JACKSON COUNTY NEAR CLARK LAKE.

SEVERE LIGHTNING..HAIL AND STRONG WINDS ARE LIKELY WITH THESE STORMS.
THERE IS A POSSIBILITY OF DAMAGING WINDS..LARGE HAIL..AND TORNADOES
AS THEY MOVE TO THE NORTHEAST AT 25 MPH.

PERSONS IN AND NEAR THE WATCH AREA SHOULD BE ALERT FOR THREATENING
CONDITIONS AND BE PREPARED TO MOVE TO SAFETY. THE STORMS ARE
DEVELOPING RAPIDLY AND COULD BECOME VERY DANGEROUS.
DGH

Special weather statement, May 17, 3:24 PM EDT, 22 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FLINT MI
320 PM EDT SAT MAY 17 1986

...TORNADO WATCH FOR SOUTH CENTRAL LOWER MICHIGAN TILL 9PM.

AT 220 PM RADAR INDICATED AN AREA OF THUNDERSTORMS IN THE LOWER
PORTIONS OF THE STATE FROM SOUTH OF MUSKEGON LANSING AND FLINT

RT

The office that day

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

Issued	Product	Office	Counties	Lasted
May 17, 2:46 PM EDT	Severe Thunderstorm Warning	DTX	Lenawee, Washtenaw	29 min
May 17, 3:16 PM EDT	Severe Thunderstorm Warning	DTX	Washtenaw	29 min
May 17, 4:10 PM EDT	Tornado Warning	DTX	Washtenaw	25 min
May 17, 4:32 PM EDT	Tornado Warning	DTX	Washtenaw, Wayne	28 min
May 17, 5:03 PM EDT	Severe Thunderstorm Warning	DTX	Wayne	57 min
May 17, 5:09 PM EDT	Tornado Warning	DTX	Midland, Saginaw	51 min
May 17, 7:51 PM EDT	Severe Thunderstorm Warning	DTX	Saginaw, Shiawassee	39 min

Nearby

Severe Thunderstorm Warnings in Michigan, 1986 Every severe thunderstorm warning in 1986

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.