Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 73, NWS Grand Rapids, MI

August 29, 2021Muskegon County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 29, 2021, 3:18 PM EDT for Muskegon County, Michigan. It was in force for 28 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 29, 2021, 3:18 PM EDT (19:18 UTC)
Expired
Aug 29, 2021, 3:46 PM EDT
In force
28 min
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Muskegon County, MI

The radar

The Grand Rapids radar (KGRR), 70 km from the middle of the area, began a volume at 19:23 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
Aug 29, 1:46 PM EDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 7.3 hours before the alert went out and 201 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, Green Bay/Straub, WI at 12:00Z on 2021-08-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1272 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, Green Bay/Straub, WI at 12:00Z on 2021-08-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 207 square meters per square second.19395878Sfc1 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
1272 J/kg
Mixed-layer CIN
-49 J/kg
Mixed-layer LCL
845 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
207 m²/s²
0-3 km storm-relative helicity
216 m²/s²
Significant tornado parameter
1.3
Supercell composite
6.5

Open this sounding in Storm Lab

The text

As transmitted.

698 
WUUS53 KGRR 291918
SVRGRR
MIC121-292015-
/O.NEW.KGRR.SV.W.0073.210829T1918Z-210829T2015Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
318 PM EDT Sun Aug 29 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Central Muskegon County in west central Michigan...

* Until 415 PM EDT.

* At 317 PM EDT, a severe thunderstorm was located 13 miles west of
  Roosevelt Park, or 14 miles west of Muskegon, moving east at 45
  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...
  Muskegon...            Muskegon Heights...    Roosevelt Park...
  North Muskegon...      Lakewood Club...       Fruitport...
  Norton Shores...       Dalton...              Holton...
  Sullivan...            Brunswick...           Muskegon SP...
  Wolf Lake...           Duck Lake SP...        Twin Lake...
  Cloverville...         

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Large hail and damaging winds and continuous cloud to ground
lightning is occurring with this storm. Move indoors immediately.
Lightning is one of nature's leading killers. Remember, if you can
hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4344 8604 4312 8603 4312 8627 4332 8640
      4335 8641
TIME...MOT...LOC 1917Z 266DEG 38KT 4320 8655 

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

$$

NJJ
1 follow-up statement
453 
WWUS53 KGRR 291946
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
346 PM EDT Sun Aug 29 2021

MIC121-291955-
/O.CAN.KGRR.SV.W.0073.000000T0000Z-210829T2015Z/
Muskegon MI-
346 PM EDT Sun Aug 29 2021

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL MUSKEGON 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.  However, gusty winds are
still possible with this thunderstorm.

A Severe Thunderstorm Watch remains in effect until 700 PM EDT for
west central Michigan.

LAT...LON 4344 8604 4312 8603 4312 8627 4332 8640
      4335 8641
TIME...MOT...LOC 1944Z 266DEG 38KT 4322 8613 

$$

JC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 28, 9:02 PM EDTSpecial Weather StatementGRRClinton58 min
Aug 28, 11:14 PM EDTSpecial Weather StatementGRRClinton61 min
Aug 29, 2:21 AM EDTAreal Flood AdvisoryGRRMason5 hr
Aug 29, 1:54 PM EDTSpecial Marine WarningGRR2 hr
Aug 29, 2:33 PM EDTFlash Flood Warning Considerable damage threatGRRLake8 hr
Aug 29, 2:49 PM EDTSpecial Marine WarningGRR113 min
Aug 29, 3:11 PM EDTAreal Flood WarningGRRMason17 hr
Aug 29, 3:26 PM EDTSevere Thunderstorm WarningGRRBarry, Ionia, Kent28 min
Aug 29, 4:04 PM EDTSevere Thunderstorm WarningGRRClinton, Ionia56 min
Aug 29, 5:21 PM EDTSevere Thunderstorm WarningGRRIngham24 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.