Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 28, NWS Grand Rapids, MI

July 7, 2021Clinton County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Jul 7, 2021, 1:45 PM EDT for Clinton County, Michigan. It was in force for 13 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 7, 2021, 1:45 PM EDT (17:45 UTC)
Expired: Jul 7, 2021, 1:58 PM EDT
In force: 13 min
Issued by: NWS Grand Rapids, MI
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

County Clinton County, MI

The radar

The Detroit radar (KDTX), 87 km from the middle of the area, began a volume at 17:48 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
Jul 7, 1:31 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 5.8 hours before the alert went out and 89 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: 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.

838 
WUUS53 KGRR 071745
SVRGRR
MIC037-071815-
/O.NEW.KGRR.SV.W.0028.210707T1745Z-210707T1815Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
145 PM EDT Wed Jul 7 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Northeastern Clinton County in south central Michigan...

* Until 215 PM EDT.

* At 144 PM EDT, a severe thunderstorm was located near St. Johns,
  moving east at 20 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...
  St. Johns...           Elsie...               Ovid...

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 4296 8454 4307 8454 4309 8437 4301 8436
      4293 8437
TIME...MOT...LOC 1744Z 273DEG 18KT 4300 8445 

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

NJJ

1 follow-up statement

033 
WWUS53 KGRR 071758
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
158 PM EDT Wed Jul 7 2021

MIC037-071808-
/O.CAN.KGRR.SV.W.0028.000000T0000Z-210707T1815Z/
Clinton MI-
158 PM EDT Wed Jul 7 2021

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN CLINTON COUNTY IS
CANCELLED...
                
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 has been cancelled.

A Severe Thunderstorm Watch remains in effect until 900 PM EDT for
south central Michigan.

LAT...LON 4296 8454 4307 8454 4309 8437 4301 8436
      4293 8437
TIME...MOT...LOC 1756Z 273DEG 18KT 4300 8435 

$$

NJJ

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 6, 8:28 PM EDT	Areal Flood Warning	GRR	Mecosta, Newaygo	6 hr
Jul 6, 9:21 PM EDT	Special Weather Statement	GRR	Clare, Isabella, Mecosta, Montcalm, Osceola	54 min
Jul 7, 12:13 PM EDT	Special Weather Statement	GRR	Allegan, Barry, Calhoun, Clinton, Eaton, Gratiot and 11 more	4 hr
Jul 7, 12:54 PM EDT	Severe Thunderstorm Warning	GRR	Clinton, Gratiot	66 min
Jul 7, 1:18 PM EDT	Tornado Warning	GRR	Clinton, Gratiot	27 min
Jul 7, 2:37 PM EDT	Severe Thunderstorm Warning	GRR	Calhoun, Jackson	38 min
Jul 7, 2:59 PM EDT	Severe Thunderstorm Warning	GRR	Calhoun, Eaton, Ingham, Jackson	77 min
Jul 7, 4:01 PM EDT	Special Weather Statement	GRR	Clare, Lake, Osceola	119 min
Jul 7, 4:15 PM EDT	Areal Flood Advisory	GRR	Calhoun	2 hr
Jul 7, 5:06 PM EDT	Severe Thunderstorm Warning	GRR	Calhoun	24 min
Jul 7, 5:12 PM EDT	Special Weather Statement	GRR	Calhoun, Eaton, Ingham, Jackson	2 hr
Jul 7, 5:18 PM EDT	Severe Thunderstorm Warning	GRR	Ingham	27 min
Jul 7, 5:33 PM EDT	Areal Flood Advisory	GRR	Lake, Osceola	4 hr
Jul 7, 6:03 PM EDT	Special Weather Statement	GRR	Clare, Lake, Osceola	117 min
Jul 7, 6:17 PM EDT	Special Weather Statement	GRR	Clinton	58 min
Jul 7, 6:44 PM EDT	Special Weather Statement	GRR	Barry	31 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.