Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 49, NWS Grand Rapids, MI

August 11, 20214 counties in Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 11, 2021, 2:11 PM EDT for 4 counties in Michigan. It was in force for 49 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 11, 2021, 2:11 PM EDT (18:11 UTC)
Expired: Aug 11, 2021, 3:00 PM EDT
In force: 49 min
Issued by: NWS Grand Rapids, MI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Clinton County, MI, Gratiot County, MI, Ionia County, MI, Montcalm County, MI

The radar

The Grand Rapids radar (KGRR), 68 km from the middle of the area, began a volume at 18:11 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.

The watch it was issued in

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

Issued	Product	Office	Lasted
Aug 11, 11:50 AM EDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 6.2 hours before the alert went out and 116 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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.

428 
WUUS53 KGRR 111811
SVRGRR
MIC037-057-067-117-111900-
/O.NEW.KGRR.SV.W.0049.210811T1811Z-210811T1900Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
211 PM EDT Wed Aug 11 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Southern Gratiot County in central Michigan...
  Northeastern Ionia County in south central Michigan...
  Northern Clinton County in south central Michigan...
  Southeastern Montcalm County in central Michigan...

* Until 300 PM EDT.

* At 211 PM EDT, a severe thunderstorm was located near Carson City,
  or 11 miles northeast of Ionia, moving east at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* This severe thunderstorm will be near...
  Carson City around 220 PM EDT.

Other locations in the path of this severe thunderstorm include
Ithaca.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4297 8502 4316 8502 4341 8438 4297 8437
TIME...MOT...LOC 1811Z 251DEG 34KT 4311 8489 

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

$$

LAURENS

3 follow-up statements

487 
WWUS53 KGRR 111830
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
230 PM EDT Wed Aug 11 2021

MIC067-117-111839-
/O.CAN.KGRR.SV.W.0049.000000T0000Z-210811T1900Z/
Ionia MI-Montcalm MI-
230 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN IONIA AND
SOUTHEASTERN MONTCALM COUNTIES IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 500 PM EDT for
south central and central Michigan.

LAT...LON 4303 8472 4323 8484 4341 8438 4313 8437
TIME...MOT...LOC 1829Z 246DEG 44KT 4320 8460 

$$

MIC037-057-111900-
/O.CON.KGRR.SV.W.0049.000000T0000Z-210811T1900Z/
Gratiot MI-Clinton MI-
230 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR SOUTHERN GRATIOT AND NORTH CENTRAL CLINTON COUNTIES...

At 229 PM EDT, a severe thunderstorm was located 6 miles south of
Ithaca, moving northeast at 50 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

This severe thunderstorm will remain over mainly rural areas of
southern Gratiot and north central Clinton Counties, including the
following locations... Pompeii, Middleton, North Star, Ashley,
Perrinton, Eureka, and Bannister.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4303 8472 4323 8484 4341 8438 4313 8437
TIME...MOT...LOC 1829Z 246DEG 44KT 4320 8460 

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

$$

MEADE

883 
WWUS53 KGRR 111845
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
245 PM EDT Wed Aug 11 2021

MIC037-111855-
/O.CAN.KGRR.SV.W.0049.000000T0000Z-210811T1900Z/
Clinton MI-
245 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL CLINTON COUNTY
IS CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 500 PM EDT for
central Michigan.

LAT...LON 4314 8450 4331 8450 4336 8438 4319 8437
TIME...MOT...LOC 1845Z 250DEG 37KT 4326 8440 

$$

MIC057-111900-
/O.CON.KGRR.SV.W.0049.000000T0000Z-210811T1900Z/
Gratiot MI-
245 PM EDT Wed Aug 11 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM EDT
FOR SOUTHEASTERN GRATIOT COUNTY...

At 245 PM EDT, a severe thunderstorm was located near Marion Springs,
or 10 miles east of Ithaca, moving east at 45 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Ashley...              

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4314 8450 4331 8450 4336 8438 4319 8437
TIME...MOT...LOC 1845Z 250DEG 37KT 4326 8440 

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

$$

MEADE

066 
WWUS53 KGRR 111856
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
256 PM EDT Wed Aug 11 2021

MIC057-111906-
/O.EXP.KGRR.SV.W.0049.000000T0000Z-210811T1900Z/
Gratiot MI-
256 PM EDT Wed Aug 11 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN GRATIOT COUNTY
WILL EXPIRE AT 300 PM EDT...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 500 PM EDT for
central Michigan.

LAT...LON 4314 8450 4331 8450 4336 8438 4319 8437
TIME...MOT...LOC 1856Z 251DEG 34KT 4329 8429 

$$

MEADE

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 10, 8:46 PM EDT	Special Marine Warning	GRR		59 min
Aug 10, 9:22 PM EDT	Special Weather Statement	GRR	Allegan, Barry, Calhoun, Clare, Clinton, Eaton and 16 more	3 hr
Aug 10, 9:40 PM EDT	Severe Thunderstorm Warning	GRR	Allegan, Mason, Muskegon, Oceana, Ottawa, Van Buren	73 min
Aug 10, 10:02 PM EDT	Severe Thunderstorm Warning	GRR	Barry, Kalamazoo, Kent, Lake, Newaygo	58 min
Aug 10, 10:41 PM EDT	Severe Thunderstorm Warning	GRR	Calhoun, Eaton, Ionia, Mecosta, Montcalm, Osceola	64 min
Aug 10, 11:09 PM EDT	Severe Thunderstorm Warning	GRR	Clare, Clinton, Gratiot, Ingham, Isabella, Jackson	66 min
Aug 11, 11:45 AM EDT	Special Marine Warning	GRR		90 min
Aug 11, 12:40 PM EDT	Special Weather Statement	GRR	Kent	65 min
Aug 11, 12:51 PM EDT	Severe Thunderstorm Warning	GRR	Allegan, Ottawa	28 min
Aug 11, 1:07 PM EDT	Special Weather Statement	GRR	Kent	83 min
Aug 11, 1:28 PM EDT	Special Weather Statement	GRR	Calhoun, Kalamazoo	62 min
Aug 11, 1:39 PM EDT	Special Weather Statement	GRR	Clinton, Eaton, Gratiot, Ingham, Ionia, Jackson and 1 more	2 hr
Aug 11, 1:56 PM EDT	Severe Thunderstorm Warning	GRR	Calhoun	38 min
Aug 11, 2:08 PM EDT	Severe Thunderstorm Warning	GRR	Jackson	58 min
Aug 11, 2:38 PM EDT	Severe Thunderstorm Warning	GRR	Ingham	34 min
Aug 11, 6:26 PM EDT	Special Marine Warning	GRR		2 hr
Aug 11, 7:32 PM EDT	Severe Thunderstorm Warning	GRR	Muskegon	43 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2021 Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.