Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 70, NWS Grand Rapids, MI

August 28, 2021Gratiot County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 28, 2021, 5:57 PM EDT for Gratiot County, Michigan. It was in force for 48 min. 5 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: Aug 28, 2021, 5:57 PM EDT (21:57 UTC)
Expired: Aug 28, 2021, 6:45 PM EDT
In force: 48 min
Issued by: NWS Grand Rapids, MI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Gratiot County, MI

The radar

The Grand Rapids radar (KGRR), 98 km from the middle of the area, began a volume at 22:01 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

Time	Report	Where	Remark
Aug 28, 5:58 PM EDT	TSTM WND DMG	4 Wnw Saint Louis, MI	TREE ON HOUSE.
Aug 28, 6:13 PM EDT	HAIL 1	2 S Saint Louis, MI	QUARTER SIZE HAIL AT N STATE ROAD AND W LINCOLN ROAD.
Aug 28, 6:36 PM EDT	TSTM WND DMG	Breckenridge, MI	TREES DOWN ALL ALONG M 46 AND IN BRECKENRIDGE, MI.
Aug 28, 6:36 PM EDT	TSTM WND DMG	Wheeler, MI	TREE ON HOUSE.
Aug 28, 6:38 PM EDT	TSTM WND DMG	2 E Wheeler, MI	TREES AND POWER LINES DOWN IN AND EAST OF WHEELER, ESPECIALLY AT THE INTERSECTION OF M 46 AND NORTH MASON ROAD AND M 46 AND NORTH BARRY ROAD.

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, 10.0 hours before the alert went out and 119 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: 1891 J/kg
Mixed-layer CIN: -30 J/kg
Mixed-layer LCL: 860 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 65 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.8

Open this sounding in Storm Lab

The text

As transmitted.

105 
WUUS53 KGRR 282157
SVRGRR
MIC057-282245-
/O.NEW.KGRR.SV.W.0070.210828T2157Z-210828T2245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
557 PM EDT Sat Aug 28 2021

The National Weather Service in Grand Rapids has issued a

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

* Until 645 PM EDT.

* At 556 PM EDT, a severe thunderstorm was located near Breckenridge,
  or 12 miles east of Alma, moving northeast at 15 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Alma...                St. Louis...           Breckenridge...
  Wheeler...             Forest Hill...         

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4333 8460 4344 8474 4347 8466 4347 8437
      4336 8437
TIME...MOT...LOC 2156Z 246DEG 11KT 4344 8441 

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

$$

JC

1 follow-up statement

788 
WWUS53 KGRR 282215
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
615 PM EDT Sat Aug 28 2021

MIC057-282245-
/O.CON.KGRR.SV.W.0070.000000T0000Z-210828T2245Z/
Gratiot MI-
615 PM EDT Sat Aug 28 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 645 PM EDT
FOR NORTHEASTERN GRATIOT COUNTY...

At 614 PM EDT, a severe thunderstorm was located near Merrill, or 11
miles west of Freeland, moving northeast at 15 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...
Alma...                St. Louis...           Breckenridge...
Wheeler...             Forest Hill...         

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm is producing large hail in Alma. SEEK SHELTER NOW inside 
a sturdy structure and stay away from windows.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4333 8460 4344 8474 4347 8466 4347 8437
      4336 8437
TIME...MOT...LOC 2214Z 246DEG 11KT 4346 8434 

HAIL THREAT...OBSERVED
MAX HAIL SIZE...1.00 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

JC

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 8:12 PM EDT	Severe Thunderstorm Warning	GRR	Mecosta, Newaygo	48 min
Aug 28, 1:06 AM EDT	Special Marine Warning	GRR		84 min
Aug 28, 2:09 AM EDT	Special Weather Statement	GRR	Lake, Mason	66 min
Aug 28, 2:42 AM EDT	Areal Flood Advisory	GRR	Mason	6 hr
Aug 28, 2:50 AM EDT	Severe Thunderstorm Warning	GRR	Lake, Osceola	55 min
Aug 28, 3:35 AM EDT	Severe Thunderstorm Warning	GRR	Clare	55 min
Aug 28, 10:32 AM EDT	Small Craft Advisory	GRR		35 hr
Aug 28, 10:40 AM EDT	Beach Hazards Statement	GRR	Allegan, Mason, Muskegon, Oceana, Ottawa, Van Buren	35 hr
Aug 28, 3:54 PM EDT	Special Weather Statement	GRR	Clare	66 min
Aug 28, 4:07 PM EDT	Special Weather Statement	GRR	Montcalm	68 min
Aug 28, 5:43 PM EDT	Special Weather Statement	GRR	Gratiot	62 min
Aug 28, 6:43 PM EDT	Severe Thunderstorm Warning	GRR	Gratiot	47 min
Aug 28, 7:33 PM EDT	Severe Thunderstorm Warning	GRR	Gratiot	42 min
Aug 28, 7:48 PM EDT	Special Weather Statement	GRR	Clinton, Ionia	57 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.