Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 37, NWS Detroit, MI

July 7, 2021Oakland County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jul 7, 2021, 4:18 PM EDT for Oakland County, Michigan. It was in force for 57 min. 6 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
Jul 7, 2021, 4:18 PM EDT (20:18 UTC)
Expired
Jul 7, 2021, 5:15 PM EDT
In force
57 min
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Oakland County, MI

The radar

The Detroit radar (KDTX), 18 km from the middle of the area, began a volume at 20:22 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
Jul 7, 4:45 PM EDTTSTM WND DMG3 E Novi, MISTATE POLICE REPORTING WIRES DOWN ACROSS BOTH DIRECTIONS OF I-275 NEAR GRAND RIVER. SOME WIRES DOWN ON CARS.
Jul 7, 4:47 PM EDTTSTM WND DMG1 Nne Novi, MIMULTIPLE TREE LIMBS DOWNED NEAR NOVI AND 12 MILE ROADS.
Jul 7, 4:49 PM EDTTSTM WND DMG2 N Farmington, MISPOTTER REPORTS MULTIPLE TREES DOWN BLOCKING ROADWAYS ACROSS THE AREA. SOME ROADS WERE IMPASSIBLE.
Jul 7, 4:49 PM EDTTSTM WND DMG3 E Novi, MIMULTIPLE LARGE TREES UPROOTED.
Jul 7, 4:49 PM EDTTSTM WND DMGFarmington, MISOCIAL MEDIA PICTURES OF MULTIPLE LARGE TREE LIMBS DOWN IN DOWNTOWN FARMINGTON.
Jul 7, 4:58 PM EDTTSTM WND DMG2 W Beverly Hills, MISOCIAL MEDIA PICTURES OF MULTIPLE APPROX 5 INCH DIAMETER TREE LIMBS DOWN.

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
Jul 7, 1:31 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 8.3 hours before the alert went out and 20 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 2021-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1092 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 2021-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 54 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
1092 J/kg
Mixed-layer CIN
-19 J/kg
Mixed-layer LCL
779 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
54 m²/s²
0-3 km storm-relative helicity
123 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.2

Open this sounding in Storm Lab

The text

As transmitted.

682 
WUUS53 KDTX 072018
SVRDTX
MIC125-072115-
/O.NEW.KDTX.SV.W.0037.210707T2018Z-210707T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Detroit/Pontiac MI
418 PM EDT Wed Jul 7 2021

The National Weather Service in Detroit/Pontiac has issued a

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

* Until 515 PM EDT.

* At 417 PM EDT, a severe thunderstorm was located near Brighton,
  moving east at 35 mph.

  HAZARD...60 mph wind gusts and quarter size hail.

  SOURCE...Radar indicated.

  IMPACT...Hail damage to vehicles is expected. Expect wind damage 
           to roofs, siding, and trees.

* This severe thunderstorm will be near...
  South Lyon around 425 PM EDT.
  Milford around 430 PM EDT.
  Northville around 440 PM EDT.
  Novi around 445 PM EDT.
  West Bloomfield around 450 PM EDT.
  Southfield and Birmingham around 505 PM EDT.
  Troy, Royal Oak and Detroit Zoo around 510 PM EDT.
  Warren around 515 PM EDT.

Other locations impacted by this severe thunderstorm include
Franklin, Keego Harbor, Waterford, Orchard Lake, Commerce, Lathrup
Village, Auburn Hills, Bingham Farms, Lake Angelus and Farmington
Hills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4243 8366 4263 8368 4274 8310 4245 8308
TIME...MOT...LOC 2017Z 263DEG 31KT 4250 8374 

HAIL...1.00IN
WIND...60MPH
 
$$

DG
3 follow-up statements
962 
WWUS53 KDTX 072040
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
440 PM EDT Wed Jul 7 2021

MIC125-072115-
/O.CON.KDTX.SV.W.0037.000000T0000Z-210707T2115Z/
Oakland MI-
440 PM EDT Wed Jul 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR SOUTHERN OAKLAND COUNTY...

At 440 PM EDT, a severe thunderstorm was located near Novi, moving
east at 30 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  West Bloomfield around 450 PM EDT.
  Birmingham around 505 PM EDT.
  Southfield, Royal Oak and Detroit Zoo around 510 PM EDT.
  Troy around 515 PM EDT.

Other locations impacted by this severe thunderstorm include
Franklin, Keego Harbor, Waterford, Orchard Lake, Commerce, Lathrup
Village, Auburn Hills, Bingham Farms, Lake Angelus and Farmington
Hills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 4243 8366 4263 8368 4274 8310 4245 8308
TIME...MOT...LOC 2040Z 263DEG 28KT 4252 8351 

HAIL...1.00IN
WIND...60MPH
 
$$

IRL
451 
WWUS53 KDTX 072051
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
451 PM EDT Wed Jul 7 2021

MIC125-072115-
/O.CON.KDTX.SV.W.0037.000000T0000Z-210707T2115Z/
Oakland MI-
451 PM EDT Wed Jul 7 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR SOUTHERN OAKLAND COUNTY...

At 451 PM EDT, a severe thunderstorm was located over West
Bloomfield, or near Novi, moving east at 35 mph.

HAZARD...60 mph wind gusts and quarter size hail.

SOURCE...Radar indicated.

IMPACT...Hail damage to vehicles is expected. Expect wind damage to 
         roofs, siding, and trees.

This severe storm will be near...
  Southfield and Birmingham around 505 PM EDT.
  Royal Oak and Detroit Zoo around 510 PM EDT.
  Troy around 515 PM EDT.

Other locations impacted by this severe thunderstorm include
Franklin, Keego Harbor, Waterford, Orchard Lake, Commerce, Lathrup
Village, Auburn Hills, Bingham Farms, Lake Angelus and Farmington
Hills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Continuous cloud to ground lightning is occurring with this storm.
Move indoors immediately. Lightning is one of nature's leading
killers. Remember, if you can hear thunder, you are close enough to
be struck by lightning.

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

&&

LAT...LON 4244 8351 4265 8356 4274 8310 4245 8308
TIME...MOT...LOC 2051Z 263DEG 31KT 4253 8338 

HAIL...1.00IN
WIND...60MPH
 
$$

IRL
532 
WWUS53 KDTX 072115
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
515 PM EDT Wed Jul 7 2021

MIC125-072125-
/O.EXP.KDTX.SV.W.0037.000000T0000Z-210707T2115Z/
Oakland MI-
515 PM EDT Wed Jul 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN OAKLAND COUNTY HAS
EXPIRED...
        
The storm which prompted the warning is moing out of the area.
Therefore, the warning has been allowed to expire.  However gusty
winds and heavy rain are still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 900 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 4244 8351 4265 8356 4274 8310 4245 8308
TIME...MOT...LOC 2115Z 268DEG 24KT 4251 8312 

$$

KK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 6, 8:06 PM EDTSpecial Weather StatementDTXSaint Clair54 min
Jul 6, 8:07 PM EDTSpecial Marine WarningDTX53 min
Jul 6, 8:26 PM EDTSpecial Marine WarningDTX79 min
Jul 6, 9:22 PM EDTSpecial Weather StatementDTXSaginaw53 min
Jul 6, 9:31 PM EDTSevere Thunderstorm WarningDTXSaginaw25 min
Jul 6, 9:37 PM EDTSpecial Marine WarningDTX21 min
Jul 6, 9:45 PM EDTSevere Thunderstorm WarningDTXHuron41 min
Jul 6, 10:13 PM EDTSpecial Weather StatementDTXOakland62 min
Jul 6, 10:16 PM EDTSevere Thunderstorm WarningDTXLapeer, Tuscola45 min
Jul 6, 10:49 PM EDTSevere Thunderstorm WarningDTXSanilac32 min
Jul 6, 10:51 PM EDTSpecial Weather StatementDTXOakland24 min
Jul 6, 11:00 PM EDTSpecial Weather StatementDTXSaginaw30 min
Jul 7, 3:38 AM EDTSmall Craft AdvisoryDTX24 hr
Jul 7, 12:35 PM EDTSpecial Weather StatementDTXHuron70 min
Jul 7, 1:43 PM EDTSpecial Weather StatementDTXHuron47 min
Jul 7, 1:49 PM EDTSevere Thunderstorm WarningDTXShiawassee41 min
Jul 7, 1:54 PM EDTSpecial Weather StatementDTXLivingston51 min
Jul 7, 2:08 PM EDTSpecial Weather StatementDTXLenawee52 min
Jul 7, 2:24 PM EDTSpecial Marine WarningDTX48 min
Jul 7, 2:39 PM EDTSevere Thunderstorm WarningDTXMonroe50 min
Jul 7, 2:41 PM EDTSpecial Marine WarningDTX65 min
Jul 7, 2:47 PM EDTSpecial Weather StatementDTXOakland43 min
Jul 7, 2:47 PM EDTSevere Thunderstorm WarningDTXLapeer, Oakland58 min
Jul 7, 2:53 PM EDTSpecial Weather StatementDTXSaint Clair37 min
Jul 7, 2:54 PM EDTSevere Thunderstorm WarningDTXOakland46 min
Jul 7, 3:10 PM EDTSevere Thunderstorm WarningDTXSaint Clair65 min
Jul 7, 3:11 PM EDTSpecial Marine WarningDTX105 min
Jul 7, 3:26 PM EDTSevere Thunderstorm WarningDTXMacomb49 min
Jul 7, 3:38 PM EDTSevere Thunderstorm WarningDTXLivingston, Washtenaw67 min
Jul 7, 3:51 PM EDTSpecial Weather StatementDTXOakland84 min
Jul 7, 4:15 PM EDTSevere Thunderstorm WarningDTXSaint Clair30 min
Jul 7, 5:07 PM EDTSpecial Weather StatementDTXWayne53 min
Jul 7, 5:08 PM EDTSpecial Marine WarningDTX68 min
Jul 7, 5:09 PM EDTSevere Thunderstorm WarningDTXMacomb51 min
Jul 7, 5:31 PM EDTAreal Flood AdvisoryDTXMacomb, Oakland112 min
Jul 7, 5:44 PM EDTSpecial Weather StatementDTXMacomb31 min
Jul 7, 7:07 PM EDTSpecial Weather StatementDTXMonroe53 min
Jul 7, 7:22 PM EDTAreal Flood AdvisoryDTXGenesee99 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.