Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 79, NWS Grand Rapids, MI

September 7, 2021Oceana County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Sep 7, 2021, 12:54 PM EDT for Oceana County, Michigan. It was in force for 66 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: Sep 7, 2021, 12:54 PM EDT (16:54 UTC)
Expired: Sep 7, 2021, 2:00 PM EDT
In force: 66 min
Issued by: NWS Grand Rapids, MI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Oceana County, MI

The radar

The Grand Rapids radar (KGRR), 109 km from the middle of the area, began a volume at 16:54 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
Sep 7, 12:21 PM EDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 4.9 hours before the alert went out and 165 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: 14 J/kg
Mixed-layer CIN: -216 J/kg
Mixed-layer LCL: 1012 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: -120 m²/s²
0-3 km storm-relative helicity: 35 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 2.1

Open this sounding in Storm Lab

The text

As transmitted.

130 
WUUS53 KGRR 071654
SVRGRR
MIC127-071800-
/O.NEW.KGRR.SV.W.0079.210907T1654Z-210907T1800Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
1254 PM EDT Tue Sep 7 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Oceana County in west central Michigan...

* Until 200 PM EDT.

* At 1254 PM EDT, a severe thunderstorm was located near Silver Lake
  SP, or 8 miles west of Hart, moving east at 55 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Hart...                Shelby...              Hesperia...
  Pentwater...           Mears SP...            Silver Lake SP...
  Weare...               Elbridge...            Colfax...
  New Era...             Rothbury...            Walkerville...
  St. Huberts...         Stony Lake...          Crystal Valley...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4375 8646 4382 8643 4382 8604 4347 8604
      4347 8646 4360 8654 4366 8654
TIME...MOT...LOC 1654Z 270DEG 49KT 4374 8653 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

HOVING

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 7, 11:50 AM EDT	Special Marine Warning	GRR		91 min
Sep 7, 12:25 PM EDT	Severe Thunderstorm Warning	GRR	Mason	65 min
Sep 7, 12:32 PM EDT	Severe Thunderstorm Warning	GRR	Lake, Osceola	58 min
Sep 7, 12:40 PM EDT	Special Marine Warning	GRR		87 min
Sep 7, 1:08 PM EDT	Tornado Warning	GRR	Clare, Osceola	40 min
Sep 7, 1:13 PM EDT	Severe Thunderstorm Warning	GRR	Lake, Newaygo	37 min
Sep 7, 1:30 PM EDT	Special Marine Warning	GRR		60 min
Sep 7, 1:39 PM EDT	Severe Thunderstorm Warning Destructive damage threat	GRR	Osceola	38 min
Sep 7, 1:51 PM EDT	Severe Thunderstorm Warning	GRR	Muskegon, Oceana	54 min
Sep 7, 2:01 PM EDT	Lakeshore Flood Advisory	GRR	Muskegon	4 hr
Sep 7, 2:03 PM EDT	Severe Thunderstorm Warning	GRR	Clare	46 min
Sep 7, 2:13 PM EDT	Tornado Warning	GRR	Clare	30 min
Sep 7, 2:20 PM EDT	Severe Thunderstorm Warning	GRR	Isabella, Mecosta, Newaygo	55 min
Sep 7, 2:23 PM EDT	Tornado Warning	GRR	Isabella	21 min
Sep 7, 2:40 PM EDT	Severe Thunderstorm Warning	GRR	Kent, Ottawa	39 min
Sep 7, 3:04 PM EDT	Severe Thunderstorm Warning	GRR	Montcalm	56 min
Sep 7, 3:26 PM EDT	Severe Thunderstorm Warning	GRR	Clinton, Gratiot, Ionia	64 min
Sep 7, 3:37 PM EDT	Special Marine Warning	GRR		83 min
Sep 7, 4:05 PM EDT	Severe Thunderstorm Warning	GRR	Van Buren	55 min
Sep 7, 4:49 PM EDT	Severe Thunderstorm Warning	GRR	Allegan, Barry, Kalamazoo	42 min
Sep 7, 5:13 PM EDT	Severe Thunderstorm Warning	GRR	Barry, Calhoun, Eaton	47 min
Sep 7, 5:40 PM EDT	Severe Thunderstorm Warning	GRR	Ingham, Jackson	50 min
Sep 7, 6:01 PM EDT	Severe Thunderstorm Warning	GRR	Clinton	29 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.