Alert archive / Michigan / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 49, NWS Detroit, MI

July 20, 1987Saginaw County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jul 20, 1987, 7:25 PM EDT for Saginaw County, Michigan. It was in force for 65 min.

The area

The counties it named.

The facts

Issued
Jul 20, 1987, 7:25 PM EDT (23:25 UTC)
Expired
Jul 20, 1987, 8:30 PM EDT
In force
65 min
Issued by
NWS Detroit, MI
Area
Whole counties

County Saginaw County, MI

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

Detroit, MI (KFNT), launched 12:00Z, 11.4 hours before the alert went out and 85 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, Detroit, MI at 12:00Z on 1987-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3198 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, Detroit, MI at 12:00Z on 1987-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 89 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
3198 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
697 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
89 m²/s²
0-3 km storm-relative helicity
101 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 KFNT 202325
SVRFNT
MIC145-210030-
 
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE FLINT MI
725 PM EDT MON JUL 20 1987
 
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL  830 PM EDT FOR PEOPLE IN THE FOLLOWING COUNTY...
 
IN CENTRAL LOWER MICHIGAN
          ...SAGINAW
 
AT 725 PM EDT RADAR SHOWS A LINE OF THUNDERSTORMS MOVING
INTO NORTHWEST SAGINAW COUNTY.  WIND DAMAGE HAVE BEEN REPORTED
TO SAGINAW COUNTY SHERIFF... WIND ESTIMATED IN EXCESS OF 55 MPH.
 
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING.  DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE AWAY FROM WINDOWS UNTIL THE STORM HAS PASSED.

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, Jul 20, 3:30 PM EDT, 3 hours 55 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FLINT MI
330 PM EDT MON JULY 20 1987

     ...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10PM EDT...

AT 320 PM WEATHER RADAR SHOWED SCATTERED THUNDERSTORMS DEVELOPING
WEST AND SOUTH OF SAGINAW BAY... AND ABOUT 10 MILES EAST OF FLINT.
NO SEVERE ACTIVITY HAS BEEN REPORTED BUT SOME SEVERE THUNDERSTORMS
COULD DEVELOP THIS AFTERNOON.

MOVEMENT OF THE DEVELOPING THUNDERSTORMS HAS NOT BEEN DETERMINED.

PERSONS IN THE THUNDERSTORM WATCH AREA ARE ADVISED TO REMAIN ALERT
TO THE POSSIBLE DEVELOPMENT OF SEVERE THUNDERSTORMS... WITH LARGE
HAIL... STRONG GUSTY WINDS... AND DANGEROUS LIGHTNING.

MOVE TO A PLACE OF SAFETY IF THREATENING WEATHER APPROACH"ES

STJ
Special weather statement, Jul 20, 4:30 PM EDT, 2 hours 55 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FLINT MI
430 PM EDT MON JULY 20 1987

     ...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10PM EDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING FOR ALL OF EAST CENTRAL LOWER MICHIGAN.

WEATHER RADAR INDICATES SOME WIDELY SCATTERED SHOWER AND THUNDERSHOWER
ACTIVITY IN THE THUMB AREA OF EAST CENTRAL LOWER MICHIGAN..EAST AND
NORTHEAST OF FLINT. MOVEMENT IS SLOWLY TO THE EAST NORTHEAST.

A WEAK STATIONARY FRONT AND APPROACHING TROUGH WILL COUPLE WITH HIGH
TEMPERATURES AND AN ABUNDANCE OF MOIST AIR TO CREATE THE POTENTIAL FOR
SEVERE THUNDERSTORMS THROUGH THE EARLY EVENING HOURS IN EAST CENTRAL
LOWER MICHIGAN..AS WELL AS MOST OF THE REMAINDER OF THE LOWER
PENINSULA. THESE STORMS..WHEN SEVERE..CREATE STRONG THUNDERSTORMS
WINDS IN EXCESS OF 58 MILES AN HOUR..DANGEROUS LIGHTNING..LARGE
HAIL..AND OFTEN SPAWN TORNADOES WITH LITTLE OR NO ADVANCE WARNING.

NO SEVERE WEATHER HAS BEEN REPORTED AS OF YET..HOWEVER THERE EXISTS
THE THREAT OF SEVERE THUNDERSTORMS IN AND NEAR THE WATCH AREA FOR THE
NEXT FEW HOURS. PERSONS IN THE WATCH AREA ARE URGED TO MONITOR WEATHER
CONDITIONS CLOSELY BY LISTENING TO NOAA WEATHER RADIO..OR LOCAL
TELEVISION AND COMMERCIAL RADIO STATIONS FOR FURTHER UPDATES AND
POSSIBLE WARNINGS.

KEITH DICKS
WSO FLINT MI
Special weather statement, Jul 20, 5:41 PM EDT, 1 hour 44 minutes before
-ARBSPSDTW
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DETROIT MI
530 PM EDT MON JULY 20 1987

AT 530 PM EDT...SCATTERED THUNDERSTORMS...WITH VERY HEAVY RAIN...WERE
OVER SOUTHEAST MICHIGAN. THE STORMS WERE OCCURRING AROUND THE DETROIT
METROPOLITAN AREA AND ITS SURROUNDING SUBURBS. REPORTS OF MARBLE SIZE
HAIL AND STRONG WINDS ACCOMPANIED SOME OF THE STORMS OVER INKSTER
MICHIGAN.

THE STORMS WERE MOVING EAST AT 25 MILES AN HOUR.
BAILEY
Special weather statement, Jul 20, 6:05 PM EDT, 1 hour 20 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FLINT MI
605 PM EDT MON JULY 20 1987

     ...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10PM EDT...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING FOR ALL OF EAST CENTRAL LOWER MICHIGAN.

AT 520 PM EDT NATIONAL WEATHER SERVICE WEATHER RADAT SHOWED STRONG
THUNDERSTORMS MOVING ACROSS NORTHERN LOWER MICHIGAN. THE LINE
EXTENDED FROM 40 MILES NORTH OF HAUGHTON LAKE SOUTHWEST ACROSS LAKE
MICHIGAN.

HOUGHTON LAKE WEATHER RADAR SHOWED SEVERE THUNDERSTORMS IN CRAWFORD
COUNTY... MOVING INTO ROSCOMMON COUNTY.  THESE SEVERE THUNDERSTORMS
HAVE PRODUCED A TORNADO WHEN THEY MOVED THROUGH GRAND TRAVERSE COUNTY.

OTHER... SCATTERED THUNDERSTORMS... WITH HEAVY RAIN... WERE INDICATED
OVER SOUTHEAST MICHIGAN AT 530 PM. THESE STORMS PRODUCED MARBLE
SIZE HAIL AND STRONG WINDS IN DETROIT SUBURBS.

PEOPLE IN EAST CENTRAL MICHIGAN ARE ADVISED TO REMAIN ALERT TO THE
POSSIBILITY OF SEVERE WEATHER THIS AFTERNO0ON AND EVENING...
PARTICULARLY PEOPLE IN ARENAC... MIDLAND... AND BAY COUNTIES
CAN EXPECT DEVELOPMENTS IN THE NEXT HOUR OR SO AS SEVERE WEATHER
MOVES FROM CLARE AND ISABELLA COUNTIES EASTWARD.

LARGE HAIL... VERY HEAVY RAIN... DAMAGING WIND AND DANGEROUS LIGHTNING
CAN BE EXPECTED.  TAKE COVER SHOULD SEVERE WEATHER THREATENS.

STJ

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 5:15 PM EDTSevere Thunderstorm WarningDTXCrawford45 min
Jul 20, 5:30 PM EDTSevere Thunderstorm WarningDTXRoscommon60 min
Jul 20, 5:30 PM EDTSevere Thunderstorm WarningDTXClare75 min
Jul 20, 6:00 PM EDTSevere Thunderstorm WarningDTXGladwin, Ogemaw60 min
Jul 20, 6:33 PM EDTSevere Thunderstorm WarningDTXArenac42 min
Jul 20, 6:46 PM EDTSevere Thunderstorm WarningDTXMidland44 min
Jul 20, 7:12 PM EDTSevere Thunderstorm WarningDTXBay63 min
Jul 20, 7:12 PM EDTSevere Thunderstorm WarningDTXHuron63 min
Jul 20, 7:34 PM EDTSevere Thunderstorm WarningDTXGenesee, Shiawassee56 min
Jul 20, 7:34 PM EDTSevere Thunderstorm WarningDTXTuscola56 min
Jul 20, 7:49 PM EDTSevere Thunderstorm WarningDTXOakland56 min

Nearby

Severe Thunderstorm Warnings in Michigan, 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.