Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 74, NWS Detroit, MI

August 11, 2021Oakland County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Aug 11, 2021, 3:09 PM EDT for Oakland County, Michigan. It was in force for 66 min. 7 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, 3:09 PM EDT (19:09 UTC)
Expired
Aug 11, 2021, 4:15 PM EDT
In force
66 min
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Oakland County, MI

The radar

The Detroit radar (KDTX), 10 km from the middle of the area, began a volume at 19:12 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 DMG2 Ssw Milford, MIREPORT OF LARGE TREE DOWN ON MILFORD RD NEAR ENTRANCE TO KENSINGTON METROPARK.
Aug 11, 3:30 PM EDTTSTM WND DMG4 E Fenton, MISEVERAL 10-12 INCH DIAMETER TREE LIMBS DOWN.
Aug 11, 3:30 PM EDTTSTM WND DMGHighland, MIREPORT OF MULTIPLE WIRES AND TREES DOWN THROUGHOUT HIGHLAND TOWNSHIP.
Aug 11, 3:42 PM EDTTSTM WND GST 601 E Ortonville, MICOUNTY OFFICIAL ESTIMATES 60 MPH GUST.
Aug 11, 3:43 PM EDTTSTM WND DMGBerkley, MIREPORTS FROM SEVERAL SOURCES OF TREES AND POWER LINES DOWN NEAR BERKLEY.
Aug 11, 3:44 PM EDTTSTM WND DMGAuburn Hills, MILARGE TREE DOWN IN BACKYARD.
Aug 11, 3:53 PM EDTTSTM WND GST 60Ese Oxford, MIMEASURED VIA MESONET.

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, 7.2 hours before the alert went out and 12 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.

889 
WUUS53 KDTX 111909
SVRDTX
MIC125-112015-
/O.NEW.KDTX.SV.W.0074.210811T1909Z-210811T2015Z/

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

The National Weather Service in Detroit/Pontiac has issued a

* Severe Thunderstorm Warning for...
  Oakland County in southeastern Michigan...

* Until 415 PM EDT.

* At 309 PM EDT, a severe thunderstorm was located near Brighton,
  moving east at 45 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Milford around 320 PM EDT.
  Novi around 325 PM EDT.
  West Bloomfield around 330 PM EDT.
  Pontiac and Birmingham around 340 PM EDT.
  Troy and Rochester around 350 PM EDT.
  Sterling Heights around 355 PM EDT.

Other locations impacted by this severe thunderstorm include
Franklin, Keego Harbor, Waterford, Orchard Lake, Holly State
Recreation Area, Commerce, Rose Center, Lathrup Village, Auburn Hills
and Bingham Farms.

People attending DTE Energy Music Theatre, and Festival of the Hills
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 4243 8366 4287 8369 4289 8310 4245 8308
TIME...MOT...LOC 1909Z 249DEG 41KT 4253 8371 

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

$$

KDK
4 follow-up statements
720 
WWUS53 KDTX 111921
SVSDTX

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

MIC125-112015-
/O.CON.KDTX.SV.W.0074.000000T0000Z-210811T2015Z/
Oakland MI-
321 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR OAKLAND COUNTY...

At 320 PM EDT, severe thunderstorms were located along a line
extending from near Goodrich to near Salem, 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...
  Ortonville around 325 PM EDT.
  Oxford and West Bloomfield around 335 PM EDT.
  Southfield and Birmingham around 340 PM EDT.
  Royal Oak and Detroit Zoo around 345 PM EDT.
  Warren and Troy around 350 PM EDT.
  Sterling Heights around 355 PM EDT.

Other locations impacted by these severe thunderstorms include
Franklin, Keego Harbor, Waterford, Orchard Lake, Holly State
Recreation Area, Commerce, Rose Center, Lathrup Village, Auburn Hills
and Bingham Farms.

People attending DTE Energy Music Theatre, and Festival of the Hills
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 4243 8366 4287 8369 4289 8310 4245 8308
TIME...MOT...LOC 1920Z 251DEG 44KT 4286 8354 4243 8355 

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

$$

BT
041 
WWUS53 KDTX 111936
SVSDTX

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

MIC125-112015-
/O.CON.KDTX.SV.W.0074.000000T0000Z-210811T2015Z/
Oakland MI-
336 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR OAKLAND COUNTY...

At 335 PM EDT, severe thunderstorms were located along a line
extending from near Metamora to near Clarkston to Southfield, 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...
  Oxford around 340 PM EDT.
  Royal Oak and Detroit Zoo around 345 PM EDT.
  Warren and Rochester around 350 PM EDT.
  Sterling Heights around 355 PM EDT.

Other locations impacted by these severe thunderstorms include
Franklin, Keego Harbor, Waterford, Orchard Lake, Holly State
Recreation Area, Commerce, Rose Center, Lathrup Village, Auburn Hills
and Bingham Farms.

People attending DTE Energy Music Theatre, and Festival of the Hills
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 4243 8366 4287 8369 4289 8310 4245 8308
TIME...MOT...LOC 1935Z 253DEG 42KT 4288 8332 4273 8332 4247 8327 

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

$$

BT
412 
WWUS53 KDTX 112003
SVSDTX

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

MIC125-112015-
/O.CON.KDTX.SV.W.0074.000000T0000Z-210811T2015Z/
Oakland MI-
403 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 415 PM EDT
FOR EASTERN OAKLAND COUNTY...

At 402 PM EDT, severe thunderstorms were located along a line
extending from near Lapeer to near Oxford to near Warren, moving east
at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

These severe thunderstorms will remain over mainly rural areas of
eastern Oakland County, including the following locations...
Rochester Hills, Madison Heights, Lakeville, Clawson, Berkley, Oak
Park, Hazel Park, Lake Orion, Sylvan Lake and Lathrup Village.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4244 8327 4288 8345 4289 8310 4245 8308
TIME...MOT...LOC 2002Z 249DEG 42KT 4306 8336 4279 8315 4252 8296 

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

$$

BT
802 
WWUS53 KDTX 112015
SVSDTX

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

MIC125-112025-
/O.EXP.KDTX.SV.W.0074.000000T0000Z-210811T2015Z/
Oakland MI-
415 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN OAKLAND COUNTY HAS
EXPIRED...
    
The storms which prompted the warning have moved out of the area.
Therefore, the warning has been allowed to expire.

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

LAT...LON 4244 8327 4288 8345 4289 8310 4245 8308
TIME...MOT...LOC 2015Z 249DEG 41KT 4311 8318 4284 8297 4257 8279 

$$

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, 2:59 PM EDTSevere Thunderstorm WarningDTXMonroe, Wayne76 min
Aug 11, 3:02 PM EDTSpecial Weather StatementDTXGenesee58 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.