Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 11, NWS Grand Rapids, MI

June 20, 20215 counties in Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Jun 20, 2021, 7:56 PM EDT for 5 counties in Michigan. It was in force for 64 min. 2 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
Jun 20, 2021, 7:56 PM EDT (23:56 UTC)
Expired
Jun 20, 2021, 9:00 PM EDT
In force
64 min
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

Counties Allegan County, MI, Barry County, MI, Calhoun County, MI, Kalamazoo County, MI, Van Buren County, MI

The radar

The Grand Rapids radar (KGRR), 62 km from the middle of the area, began a volume at 23:59 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
Jun 20, 8:00 PM EDTTSTM WND DMG2 Nnw Schoolcraft, MIWIND GUSTS OF 50 TO 60 MPH ESTIMATED. BRANCHES DOWN. VERY HEAVY RAINFALL WITH VISIBILITY NEAR ZERO.
Jun 20, 8:18 PM EDTTSTM WND DMG3 W Fulton, MIREPORT FROM MPING: 1-INCH TREE LIMBS BROKEN; SHINGLES BLOWN OFF.

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
Jun 20, 6:06 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 11.9 hours before the alert went out and 182 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 2021-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 46 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 2021-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 77 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
46 J/kg
Mixed-layer CIN
-265 J/kg
Mixed-layer LCL
737 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
77 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

823 
WUUS53 KGRR 202356
SVRGRR
MIC005-015-025-077-159-210100-
/O.NEW.KGRR.SV.W.0011.210620T2356Z-210621T0100Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
756 PM EDT Sun Jun 20 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Calhoun County in south central Michigan...
  Van Buren County in southwestern Michigan...
  Allegan County in southwestern Michigan...
  Southern Barry County in southwestern Michigan...
  Kalamazoo County in southwestern Michigan...

* Until 900 PM EDT.

* At 755 PM EDT, severe thunderstorms were located along a line
  extending from near South Haven to near Mattawan to 5 miles
  northeast of Centreville, moving northeast 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.

* Locations impacted include...
  Kalamazoo...           Portage...             Albion...
  Hastings...            Marshall...            Battle Creek...
  Allegan...             South Haven...         Paw Paw...
  Wayland...             Otsego...              Plainwell...
  Vicksburg...           Hartford...            Galesburg...
  Mattawan...            Lawton...              Bangor...
  Decatur...             Homer...               

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with these storms. 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.

&&

LAT...LON 4207 8622 4224 8622 4224 8637 4246 8626
      4274 8600 4263 8523 4250 8507 4242 8507
      4242 8497 4221 8471 4207 8471
TIME...MOT...LOC 2355Z 232DEG 28KT 4237 8620 4219 8579 4200 8547 

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

DUKE
2 follow-up statements
035 
WWUS53 KGRR 210024
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
824 PM EDT Sun Jun 20 2021

MIC159-210034-
/O.CAN.KGRR.SV.W.0011.000000T0000Z-210621T0100Z/
Van Buren MI-
824 PM EDT Sun Jun 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR VAN BUREN COUNTY IS
CANCELLED...

The storms which prompted the warning have weakened and moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 100 AM EDT for
south central and southwestern Michigan.

LAT...LON 4207 8542 4243 8576 4243 8626 4248 8624
      4274 8600 4263 8523 4250 8507 4242 8507
      4242 8497 4221 8471 4207 8471
TIME...MOT...LOC 0024Z 244DEG 36KT 4249 8589 4231 8548 4212 8516 

$$

MIC005-015-025-077-210100-
/O.CON.KGRR.SV.W.0011.000000T0000Z-210621T0100Z/
Calhoun MI-Allegan MI-Barry MI-Kalamazoo MI-
824 PM EDT Sun Jun 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR CALHOUN...ALLEGAN...SOUTHERN BARRY AND KALAMAZOO COUNTIES...

At 824 PM EDT, severe thunderstorms were located along a line
extending from near Allegan to near Comstock Northwest to near Union
City, moving northeast at 40 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.

Locations impacted include...
Kalamazoo...           Portage...             Albion...
Hastings...            Marshall...            Battle Creek...
Allegan...             Wayland...             Otsego...
Plainwell...           Galesburg...           Homer...
Union City...          Fennville...           Climax...
Richland...            Martin...              Burlington...
Brownlee Park...       Comstock Northwest...  

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 these storms.
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.

&&

LAT...LON 4207 8542 4243 8576 4243 8626 4248 8624
      4274 8600 4263 8523 4250 8507 4242 8507
      4242 8497 4221 8471 4207 8471
TIME...MOT...LOC 0024Z 244DEG 36KT 4249 8589 4231 8548 4212 8516 

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

04
135 
WWUS53 KGRR 210044
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
844 PM EDT Sun Jun 20 2021

MIC005-077-210053-
/O.CAN.KGRR.SV.W.0011.000000T0000Z-210621T0100Z/
Allegan MI-Kalamazoo MI-
844 PM EDT Sun Jun 20 2021

...THE SEVERE THUNDERSTORM WARNING FOR ALLEGAN AND KALAMAZOO COUNTIES
IS CANCELLED...

The storms which prompted the warning have weakened and moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 100 AM EDT for
south central and southwestern Michigan.

LAT...LON 4208 8507 4242 8530 4242 8554 4248 8553
      4267 8554 4263 8523 4250 8507 4242 8507
      4242 8497 4221 8471 4207 8471
TIME...MOT...LOC 0043Z 233DEG 40KT 4264 8562 4246 8521 4227 8489 

$$

MIC015-025-210100-
/O.CON.KGRR.SV.W.0011.000000T0000Z-210621T0100Z/
Calhoun MI-Barry MI-
844 PM EDT Sun Jun 20 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 900 PM EDT
FOR CALHOUN AND SOUTHERN BARRY COUNTIES...

At 843 PM EDT, severe thunderstorms were located along a line
extending from near Wayland to 7 miles northeast of Level Park-Oak
Park to near Marshall, moving northeast at 45 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.

Locations impacted include...
Albion...              Hastings...            Marshall...
Battle Creek...        Homer...               Burlington...
Brownlee Park...       Level Park-Oak Park... Orangeville...
Marengo...             Assyria...             Tekonsha...
Delton...              Banfield...            Gun Lake...
Yankee Springs...      Prairieville...        Hickory Corners...
Dowling...             Pine Lake...           

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 these storms.
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.

&&

LAT...LON 4208 8507 4242 8530 4242 8554 4248 8553
      4267 8554 4263 8523 4250 8507 4242 8507
      4242 8497 4221 8471 4207 8471
TIME...MOT...LOC 0043Z 233DEG 40KT 4264 8562 4246 8521 4227 8489 

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

04

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 4:50 AM EDTSmall Craft AdvisoryGRR45 hr
Jun 20, 4:52 AM EDTBeach Hazards StatementGRRAllegan, Mason, Muskegon, Oceana, Ottawa, Van Buren45 hr
Jun 20, 7:05 PM EDTSevere Thunderstorm WarningGRRVan Buren55 min
Jun 20, 7:13 PM EDTSpecial Marine WarningGRR92 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.