Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 73, NWS Detroit, MI

August 11, 2021Monroe County, Wayne County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Aug 11, 2021, 2:59 PM EDT for Monroe County, Wayne County, Michigan. It was in force for 76 min. 8 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 11, 2021, 2:59 PM EDT (18:59 UTC)
Expired
Aug 11, 2021, 4:15 PM EDT
In force
76 min
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Monroe County, MI, Wayne County, MI

The radar

The Detroit radar (KDTX), 69 km from the middle of the area, began a volume at 18:59 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

TimeReportWhereRemark
Aug 11, 3:17 PM EDTTSTM WND DMG5 S Dundee, MIREPORTS OF NUMEROUS TREES AND POWER LINES DOWN.
Aug 11, 3:21 PM EDTTSTM WND DMGIda, MITREE LINE FLATTENED. REPORTS OF OVER 40 TREES DOWN IN THE AREA VIA DISPATCH.
Aug 11, 3:23 PM EDTTSTM WND GST 605 Ssw Canton, MIMEASURED AT DETROIT WILLOW RUN AIRPORT.
Aug 11, 3:30 PM EDTTSTM WND DMG5 Ssw Romulus, MILARGE TREE OVER 1.5 FOOT DIAMETER DOWN ON POWER LINE.
Aug 11, 3:30 PM EDTTSTM WND DMGMonroe, MISEVERAL LARGE TREE LIMBS DOWN AND SOME LARGE TREES UPROOTED. REPORTS RELAYED VIA SOCIAL MEDIA PHOTOS.
Aug 11, 3:43 PM EDTTSTM WND DMGWyandotte, MILARGE TREE ACROSS ROAD NEAR HENRY FORD HOSPITAL IN WYANDOTTE.
Aug 11, 3:44 PM EDTTSTM WND GST 632 Ene Romulus, MIMEASURED AT DETROIT METRO AIRPORT...CORRECTED AS TSTM WIND GST.
Aug 11, 3:44 PM EDTNON-TSTM WND GST 632 Ene Romulus, MIMEASURED AT DETROIT METRO AIRPORT.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 11, 2:32 PM EDTSevere Thunderstorm WatchSPC4 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 7.0 hours before the alert went out and 70 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 2021-08-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 106 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 12:00Z on 2021-08-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 169 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
106 J/kg
Mixed-layer CIN
-290 J/kg
Mixed-layer LCL
1220 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
169 m²/s²
0-3 km storm-relative helicity
167 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

165 
WUUS53 KDTX 111859
SVRDTX
MIC115-163-112015-
/O.NEW.KDTX.SV.W.0073.210811T1859Z-210811T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Detroit/Pontiac MI
259 PM EDT Wed Aug 11 2021

The National Weather Service in Detroit/Pontiac has issued a

* Severe Thunderstorm Warning for...
  Monroe County in southeastern Michigan...
  Wayne County in southeastern Michigan...

* Until 415 PM EDT.

* At 258 PM EDT, severe thunderstorms were located along a line
  extending from near Dexter to near Morenci, moving east at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

  IMPACT...Expect damage to roofs, siding, and trees.

* Severe thunderstorms will be near...
  Canton, Northville, Petersburg and Ottawa Lake around 325 PM EDT.
  Lambertville around 330 PM EDT.
  Livonia, Temperance and Ida around 335 PM EDT.
  Monroe and Luna Pier around 345 PM EDT.

Other locations impacted by these severe thunderstorms include
Newport, Melvindale, Gibraltar, Erie, New Boston, Woodland Beach,
Stony Point, Bolles Harbor, Rockwood and Samaria.

People attending the Aretha Franklin Amphitheater should seek safe
shelter immediately!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4208 8377 4209 8354 4243 8355 4245 8284
      4236 8290 4232 8306 4229 8309 4224 8313
      4199 8313 4190 8325 4189 8331 4182 8337
      4173 8340 4172 8376
TIME...MOT...LOC 1858Z 257DEG 40KT 4239 8387 4176 8411 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

KDK
4 follow-up statements
852 
WWUS53 KDTX 111915
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
315 PM EDT Wed Aug 11 2021

MIC115-163-112015-
/O.CON.KDTX.SV.W.0073.000000T0000Z-210811T2015Z/
Monroe MI-Wayne MI-
315 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR MONROE AND WAYNE COUNTIES...

At 313 PM EDT, severe thunderstorms were located along a line
extending from near South Lyon to near Ottawa Lake, moving east at 50
mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Canton and Northville around 325 PM EDT.
  Livonia around 335 PM EDT.
  Luna Pier around 340 PM EDT.

Other locations impacted by these severe thunderstorms include
Newport, Melvindale, Gibraltar, Erie, New Boston, Woodland Beach,
Stony Point, Bolles Harbor, Rockwood and Samaria.

People attending the Aretha Franklin Amphitheater should seek safe
shelter immediately!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms produced wind damage across Lenawee county. SEEK 
SHELTER NOW inside a sturdy structure and stay away from windows.
 
&&

LAT...LON 4208 8377 4209 8354 4243 8355 4245 8284
      4236 8290 4232 8306 4229 8309 4224 8313
      4199 8313 4190 8325 4189 8331 4182 8337
      4173 8340 4172 8376
TIME...MOT...LOC 1913Z 257DEG 42KT 4241 8367 4173 8381 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

BT
542 
WWUS53 KDTX 111933
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
333 PM EDT Wed Aug 11 2021

MIC115-163-112015-
/O.CON.KDTX.SV.W.0073.000000T0000Z-210811T2015Z/
Monroe MI-Wayne MI-
333 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR MONROE AND WAYNE COUNTIES...

At 331 PM EDT, severe thunderstorms were located along a line
extending from near Southfield to near Flat Rock to near Luna Pier,
moving east at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated with 60 mph gust observed at Ypsilanti airport.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Livonia and Flat Rock around 335 PM EDT.
  Taylor, Trenton and Grosse Ile around 340 PM EDT.
  Wyandotte around 345 PM EDT.
  Downtown Detroit around 350 PM EDT.
  Belle Isle around 355 PM EDT.

Other locations impacted by these severe thunderstorms include
Newport, Melvindale, Gibraltar, Erie, New Boston, Woodland Beach,
Stony Point, Bolles Harbor, Rockwood and Samaria.

People attending the Aretha Franklin Amphitheater should seek safe
shelter immediately!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4208 8377 4209 8354 4243 8355 4245 8284
      4236 8290 4232 8306 4229 8309 4224 8313
      4199 8313 4190 8325 4189 8331 4182 8337
      4173 8340 4172 8376
TIME...MOT...LOC 1931Z 252DEG 45KT 4246 8332 4215 8333 4177 8345 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

BT
568 
WWUS53 KDTX 111956
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
356 PM EDT Wed Aug 11 2021

MIC115-163-112015-
/O.CON.KDTX.SV.W.0073.000000T0000Z-210811T2015Z/
Monroe MI-Wayne MI-
356 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR EASTERN MONROE AND CENTRAL WAYNE COUNTIES...

At 355 PM EDT, severe thunderstorms were located along a line
extending from near Warren to 6 miles east of Grosse Ile to near
Temperance, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

IMPACT...Expect damage to roofs, siding, and trees.

These severe storms will be near...
  Grosse Pointe around 400 PM EDT.

Other locations impacted by these severe thunderstorms include
Newport, Melvindale, Gibraltar, Woodland Beach, Stony Point, Bolles
Harbor, Rockwood, Harper Woods, Grosse Pointe Shores and Ecorse.

People attending the Aretha Franklin Amphitheater should seek safe
shelter immediately!

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with these storms, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4173 8352 4208 8330 4244 8326 4245 8284
      4236 8290 4232 8306 4224 8313 4209 8313
      4205 8315 4199 8313 4190 8325 4189 8331
      4182 8337 4173 8340
TIME...MOT...LOC 1955Z 258DEG 40KT 4245 8301 4214 8302 4175 8349 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...OBSERVED
MAX WIND GUST...60 MPH

$$

BT
621 
WWUS53 KDTX 112012
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
412 PM EDT Wed Aug 11 2021

MIC115-163-112022-
/O.EXP.KDTX.SV.W.0073.000000T0000Z-210811T2015Z/
Monroe MI-Wayne MI-
412 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN MONROE AND EASTERN
WAYNE COUNTIES WILL EXPIRE AT 415 PM EDT...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 800 PM EDT for
southeastern Michigan.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Detroit/Pontiac.

LAT...LON 4173 8352 4208 8330 4244 8326 4245 8284
      4236 8290 4232 8306 4224 8313 4209 8313
      4205 8315 4199 8313 4190 8325 4189 8331
      4182 8337 4173 8340
TIME...MOT...LOC 2012Z 257DEG 40KT 4249 8279 4218 8281 4179 8328 

$$

BT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 10, 11:43 PM EDTSevere Thunderstorm WarningDTXBay, Midland, Saginaw62 min
Aug 10, 11:53 PM EDTSpecial Weather StatementDTXGenesee, Livingston, Shiawassee, Washtenaw52 min
Aug 10, 11:58 PM EDTSpecial Marine WarningDTX92 min
Aug 11, 12:02 AM EDTSevere Thunderstorm WarningDTXGenesee, Livingston, Oakland, Shiawassee, Washtenaw58 min
Aug 11, 12:43 AM EDTSevere Thunderstorm WarningDTXBay, Huron, Saginaw, Tuscola47 min
Aug 11, 1:09 AM EDTSpecial Marine WarningDTX81 min
Aug 11, 1:11 AM EDTSpecial Weather StatementDTXHuron49 min
Aug 11, 1:29 AM EDTSpecial Marine WarningDTX46 min
Aug 11, 4:04 AM EDTHeat AdvisoryDTXLenawee, Livingston, Macomb, Monroe, Oakland, Washtenaw and 1 more13 hr
Aug 11, 2:22 PM EDTSevere Thunderstorm WarningDTXLenawee, Washtenaw68 min
Aug 11, 2:31 PM EDTSevere Thunderstorm WarningDTXSaginaw42 min
Aug 11, 2:42 PM EDTSevere Thunderstorm WarningDTXLivingston63 min
Aug 11, 3:02 PM EDTSpecial Weather StatementDTXGenesee58 min
Aug 11, 3:09 PM EDTSevere Thunderstorm WarningDTXOakland66 min
Aug 11, 3:16 PM EDTSevere Thunderstorm WarningDTXGenesee, Shiawassee59 min
Aug 11, 3:17 PM EDTSpecial Marine WarningDTX88 min
Aug 11, 3:36 PM EDTSpecial Marine WarningDTX84 min
Aug 11, 3:36 PM EDTSevere Thunderstorm WarningDTXLapeer, Macomb, Saint Clair, Sanilac69 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2021Every severe thunderstorm warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.