Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 23, NWS Detroit, MI

June 29, 2021Washtenaw County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Jun 29, 2021, 2:02 PM EDT for Washtenaw County, Michigan. It was in force for 58 min. 1 report 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
Jun 29, 2021, 2:02 PM EDT (18:02 UTC)
Expired
Jun 29, 2021, 3:00 PM EDT
In force
58 min
Issued by
NWS Detroit, MI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Washtenaw County, MI

The radar

The Detroit radar (KDTX), 49 km from the middle of the area, began a volume at 18:03 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
Jun 29, 2:11 PM EDTTSTM WND DMG3 Ssw Whitmore Lake, MIPOWER LINES WERE REPORTED BLOWN DOWN.

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

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 6.0 hours before the alert went out and 52 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 2021-06-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 681 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 2021-06-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 108 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
681 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
1064 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
108 m²/s²
0-3 km storm-relative helicity
105 m²/s²
Significant tornado parameter
0.2
Supercell composite
2.3

Open this sounding in Storm Lab

The text

As transmitted.

958 
WUUS53 KDTX 291802
SVRDTX
MIC161-291900-
/O.NEW.KDTX.SV.W.0023.210629T1802Z-210629T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Detroit/Pontiac MI
202 PM EDT Tue Jun 29 2021

The National Weather Service in Detroit/Pontiac has issued a

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

* Until 300 PM EDT.

* At 201 PM EDT, a severe thunderstorm was located near Dexter,
  moving east at 20 mph.

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

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Dexter around 210 PM EDT.
  Ann Arbor and Saline around 220 PM EDT.

Other locations in the path of this severe thunderstorm include
Dixboro, Ypsilanti, Salem and Canton.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Damaging winds and 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 8399 4242 8388 4244 8356 4243 8355
      4229 8354 4213 8354 4210 8407 4237 8412
TIME...MOT...LOC 1801Z 260DEG 17KT 4226 8392 

HAIL...0.75IN
WIND...60MPH
 
$$

AA
3 follow-up statements
825 
WWUS53 KDTX 291820
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
220 PM EDT Tue Jun 29 2021

MIC161-291900-
/O.CON.KDTX.SV.W.0023.000000T0000Z-210629T1900Z/
Washtenaw MI-
220 PM EDT Tue Jun 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR CENTRAL WASHTENAW COUNTY...

At 218 PM EDT, a severe thunderstorm was located over Ypsilanti,
moving east at 30 mph.

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

SOURCE...Radar indicated.

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

Locations impacted include...
  Willis, Canton and Ann Arbor.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 4241 8355 4229 8354 4213 8354 4210 8399
      4236 8395
TIME...MOT...LOC 1818Z 264DEG 28KT 4222 8367 

HAIL...0.75IN
WIND...60MPH
 
$$

AA
637 
WWUS53 KDTX 291840
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
240 PM EDT Tue Jun 29 2021

MIC161-291900-
/O.CON.KDTX.SV.W.0023.000000T0000Z-210629T1900Z/
Washtenaw MI-
240 PM EDT Tue Jun 29 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR EASTERN WASHTENAW COUNTY...

At 239 PM EDT, a severe thunderstorm was located near Belleville, or
near Ypsilanti, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Ann Arbor, Ypsilanti, Saline, Canton, Salem, Dixboro, Willis, Barton
Hills, Pittsfield Township, Whittaker and Delhi Mills.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 4241 8355 4229 8354 4213 8354 4211 8388
      4238 8380
TIME...MOT...LOC 1839Z 260DEG 17KT 4224 8354 

HAIL...<.75IN
WIND...60MPH
 
$$

AA
734 
WWUS53 KDTX 291853
SVSDTX

Severe Weather Statement
National Weather Service Detroit/Pontiac MI
253 PM EDT Tue Jun 29 2021

MIC161-291902-
/O.EXP.KDTX.SV.W.0023.000000T0000Z-210629T1900Z/
Washtenaw MI-
253 PM EDT Tue Jun 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR EASTERN WASHTENAW COUNTY WILL
EXPIRE AT 300 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

LAT...LON 4241 8355 4229 8354 4213 8354 4211 8388
      4238 8380
TIME...MOT...LOC 1852Z 260DEG 17KT 4225 8346 

$$

AA

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 28, 8:10 PM EDTSpecial Weather StatementDTXWashtenaw50 min
Jun 28, 8:15 PM EDTSpecial Weather StatementDTXWayne60 min
Jun 28, 8:51 PM EDTSpecial Weather StatementDTXWashtenaw39 min
Jun 28, 9:09 PM EDTSpecial Weather StatementDTXMacomb, Saint Clair66 min
Jun 29, 4:24 AM EDTSpecial Weather StatementDTXLivingston, Oakland66 min
Jun 29, 12:48 PM EDTSpecial Weather StatementDTXLivingston, Shiawassee, Washtenaw57 min
Jun 29, 1:06 PM EDTSevere Thunderstorm WarningDTXGenesee, Livingston, Oakland, Shiawassee54 min
Jun 29, 1:38 PM EDTSpecial Weather StatementDTXLivingston, Washtenaw97 min
Jun 29, 1:55 PM EDTSevere Thunderstorm WarningDTXGenesee, Lapeer, Oakland38 min
Jun 29, 2:30 PM EDTSpecial Weather StatementDTXMacomb, Monroe, Oakland, Saint Clair, Wayne60 min
Jun 29, 2:56 PM EDTSpecial Marine WarningDTX70 min
Jun 29, 3:04 PM EDTSpecial Marine WarningDTX56 min
Jun 29, 3:09 PM EDTAreal Flood AdvisoryDTXMacomb, Oakland, Wayne90 min
Jun 29, 3:09 PM EDTSevere Thunderstorm WarningDTXMacomb, Wayne23 min
Jun 29, 3:28 PM EDTAreal Flood AdvisoryDTXSaint Clair73 min
Jun 29, 5:58 PM EDTSpecial Marine WarningDTX77 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.