Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 34, NWS Grand Rapids, MI

July 24, 2021Gratiot County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Jul 24, 2021, 4:38 PM EDT for Gratiot County, Michigan. It was in force for 52 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
Jul 24, 2021, 4:38 PM EDT (20:38 UTC)
Expired
Jul 24, 2021, 5:30 PM EDT
In force
52 min
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Tornado
Possible
Hail
0.75 in
Wind
60.0 mph

County Gratiot County, MI

The radar

The Grand Rapids radar (KGRR), 87 km from the middle of the area, began a volume at 20:42 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.

IssuedProductOfficeLasted
Jul 24, 3:16 PM EDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 8.6 hours before the alert went out and 108 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 2021-07-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 588 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 2021-07-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 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
588 J/kg
Mixed-layer CIN
-27 J/kg
Mixed-layer LCL
557 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
129 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.8

Open this sounding in Storm Lab

The text

As transmitted.

518 
WUUS53 KGRR 242038
SVRGRR
MIC057-242130-
/O.NEW.KGRR.SV.W.0034.210724T2038Z-210724T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
438 PM EDT Sat Jul 24 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Southern Gratiot County in central Michigan...

* Until 530 PM EDT.

* At 438 PM EDT, a severe thunderstorm was located 7 miles west of
  Ithaca, moving east at 35 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Ithaca...              Sumner...              North Star...
  Ashley...              Perrinton...           Pompeii...
  Bannister...           

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4312 8454 4325 8482 4337 8481 4332 8437
      4312 8437
TIME...MOT...LOC 2038Z 286DEG 29KT 4328 8475 

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

CAS
3 follow-up statements
446 
WWUS53 KGRR 242053
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
453 PM EDT Sat Jul 24 2021

MIC057-242130-
/O.CON.KGRR.SV.W.0034.000000T0000Z-210724T2130Z/
Gratiot MI-
453 PM EDT Sat Jul 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR SOUTHEASTERN GRATIOT COUNTY...

At 453 PM EDT, a severe thunderstorm was located near Ithaca, moving 
east at 35 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Ithaca...              North Star...          Ashley...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly 
from severe thunderstorms. If you spot a tornado go at once into the 
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4321 8459 4328 8466 4333 8461 4332 8437
      4312 8437
TIME...MOT...LOC 2052Z 281DEG 31KT 4327 8457 

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

CAS
806 
WWUS53 KGRR 242109
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
509 PM EDT Sat Jul 24 2021

MIC057-242130-
/O.CON.KGRR.SV.W.0034.000000T0000Z-210724T2130Z/
Gratiot MI-
509 PM EDT Sat Jul 24 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 530 PM EDT
FOR SOUTHEASTERN GRATIOT COUNTY...

At 509 PM EDT, a severe thunderstorm was located near Ashley, or 9 
miles southeast of Ithaca, moving east at 30 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Ashley...              

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for a possible tornado! Tornadoes can develop quickly
from severe thunderstorms. If you spot a tornado go at once into the
basement or small central room in a sturdy structure.

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

&&

LAT...LON 4320 8454 4329 8449 4331 8437 4316 8437
TIME...MOT...LOC 2109Z 289DEG 26KT 4323 8444 

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

CAS
706 
WWUS53 KGRR 242129
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
529 PM EDT Sat Jul 24 2021

MIC057-242137-
/O.EXP.KGRR.SV.W.0034.000000T0000Z-210724T2130Z/
Gratiot MI-
529 PM EDT Sat Jul 24 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN GRATIOT COUNTY
WILL EXPIRE AT 530 PM EDT...
        
The storm which prompted the warning has moved out of the area.
Therefore, the warning will be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
central Michigan.

LAT...LON 4320 8454 4329 8449 4331 8437 4316 8437
TIME...MOT...LOC 2127Z 286DEG 29KT 4319 8426 

$$

CAS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 24, 12:30 PM EDTSpecial Weather StatementGRRClare, Lake, Osceola60 min
Jul 24, 2:58 PM EDTSevere Thunderstorm WarningGRRClare32 min
Jul 24, 5:50 PM EDTSevere Thunderstorm WarningGRRAllegan, Barry, Kent, Ottawa55 min
Jul 24, 6:58 PM EDTSevere Thunderstorm WarningGRRClinton, Eaton, Ingham62 min
Jul 24, 7:17 PM EDTSevere Thunderstorm WarningGRREaton, Ingham43 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.