Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 96, NWS Grand Rapids, MI

September 13, 2021Kent County, Ottawa County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Sep 13, 2021, 11:37 AM EDT for Kent County, Ottawa County, Michigan. It was in force for 53 min. 14 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
Sep 13, 2021, 11:37 AM EDT (15:37 UTC)
Expired
Sep 13, 2021, 12:30 PM EDT
In force
53 min
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Kent County, MI, Ottawa County, MI

The radar

The Grand Rapids radar (KGRR), 33 km from the middle of the area, began a volume at 15:40 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

TimeReportWhereRemark
Sep 13, 11:55 AM EDTHAIL 0.5Hudsonville, MITIME ESTIMATED FROM RADAR.
Sep 13, 12:00 PM EDTHAIL 0.751 Sse Jenison, MIREPORT FROM MPING: DIME (0.75 IN.).
Sep 13, 12:00 PM EDTHAIL 1Jenison, MITIME ESTIMATED FROM RADAR.
Sep 13, 12:05 PM EDTHAIL 0.52 Sw Wyoming, MI
Sep 13, 12:07 PM EDTHAIL 0.51 Wsw Grandville, MIREPORT FROM MPING: HALF-INCH (0.50 IN.).
Sep 13, 12:09 PM EDTHAIL 0.251 Sw Wyoming, MI
Sep 13, 12:09 PM EDTHAIL 0.52 Ssw Grandville, MIREPORT FROM MPING: HALF-INCH (0.50 IN.).
Sep 13, 12:15 PM EDTHAIL 0.52 S Grandville, MIREPORT FROM MPING: HALF-INCH (0.50 IN.).
Sep 13, 12:15 PM EDTHAIL 0.72 Nne Dutton, MIHAIL LASTED FROM 12:15 TO 12:17 PM. MOSTLY PEA SIZE WITH A FEW LARGER TO DIME SIZE.
Sep 13, 12:18 PM EDTHAIL 0.52 E Byron Center, MIREPORT FROM MPING: HALF-INCH (0.50 IN.).
Sep 13, 12:20 PM EDTHAIL 0.752 Se Cutlerville, MIREPORT FROM MPING: DIME (0.75 IN.).
Sep 13, 12:23 PM EDTHAIL 12 Ese Dutton, MI
Sep 13, 12:27 PM EDTHAIL 0.7Caledonia, MIPEA TO DIME-SIZED HAIL.
Sep 13, 12:32 PM EDTHAIL 0.5Alto, MITIME ESTIMATED FROM RADAR.

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, 3.6 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, Detroit, MI at 12:00Z on 2021-09-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-09-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
947 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
50 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

314 
WUUS53 KGRR 131537
SVRGRR
MIC081-139-131630-
/O.NEW.KGRR.SV.W.0096.210913T1537Z-210913T1630Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
1137 AM EDT Mon Sep 13 2021

The National Weather Service in Grand Rapids has issued a

* Severe Thunderstorm Warning for...
  Kent County in southwestern Michigan...
  Ottawa County in southwestern Michigan...

* Until 1230 PM EDT.

* At 1137 AM EDT, severe thunderstorms were located along a line
  extending from near Sparta to near Allendale to near Beechwood,
  moving east at 50 mph.

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

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Grand Rapids...        Holland...             Lowell...
  Wyoming...             Kentwood...            Walker...
  Grandville...          East Grand Rapids...   Hudsonville...
  Rockford...            Zeeland...             Coopersville...
  Sparta...              Caledonia...           Allendale...
  Beechwood...           Jenison...             Holland SP...
  Ada...                 Grattan...             

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 these storms. 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 4312 8599 4312 8591 4316 8591 4321 8582
      4321 8579 4326 8579 4329 8577 4323 8531
      4277 8531 4277 8621 4299 8623
TIME...MOT...LOC 1537Z 284DEG 45KT 4321 8571 4299 8587 4283 8616 

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

$$

DUKE
3 follow-up statements
370 
WWUS53 KGRR 131600
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
1200 PM EDT Mon Sep 13 2021

MIC081-139-131630-
/O.CON.KGRR.SV.W.0096.000000T0000Z-210913T1630Z/
Kent MI-Ottawa MI-
1200 PM EDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 PM EDT
FOR KENT AND SOUTHEASTERN OTTAWA COUNTIES...

At 1200 PM EDT, a severe thunderstorm was located over Jenison, or 9
miles southwest of Grand Rapids, moving east at 40 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...
Grand Rapids...        Holland...             Lowell...
Wyoming...             Kentwood...            Walker...
Grandville...          East Grand Rapids...   Hudsonville...
Rockford...            Zeeland...             Coopersville...
Sparta...              Caledonia...           Beechwood...
Jenison...             Allendale...           Ada...
Grattan...             Cedar Springs...       

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

LAT...LON 4323 8531 4277 8531 4277 8621 4293 8605
      4328 8566
TIME...MOT...LOC 1600Z 248DEG 35KT 4289 8582 

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

$$

MEADE
170 
WWUS53 KGRR 131616
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
1216 PM EDT Mon Sep 13 2021

MIC139-131625-
/O.CAN.KGRR.SV.W.0096.000000T0000Z-210913T1630Z/
Ottawa MI-
1216 PM EDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN OTTAWA COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

LAT...LON 4302 8531 4277 8531 4277 8578 4300 8579
TIME...MOT...LOC 1615Z 271DEG 34KT 4287 8562 

$$

MIC081-131630-
/O.CON.KGRR.SV.W.0096.000000T0000Z-210913T1630Z/
Kent MI-
1216 PM EDT Mon Sep 13 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 1230 PM EDT
FOR SOUTHERN KENT COUNTY...

At 1215 PM EDT, a severe thunderstorm was located over Kentwood, or 6
miles south of Grand Rapids, moving east at 40 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...
Grand Rapids...        Lowell...              Wyoming...
Kentwood...            Walker...              Grandville...
East Grand Rapids...   Caledonia...           Ada...
Dutton...              Cutlerville...         Alto...
Alaska...              Byron Center...        Cascade...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Prepare immediately for large hail and damaging winds. People outside
should move to a shelter, inside a strong building and away from
windows.

&&

LAT...LON 4302 8531 4277 8531 4277 8578 4300 8579
TIME...MOT...LOC 1615Z 271DEG 34KT 4287 8562 

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

$$

MEADE
342 
WWUS53 KGRR 131631
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
1231 PM EDT Mon Sep 13 2021

MIC081-131639-
/O.EXP.KGRR.SV.W.0096.000000T0000Z-210913T1630Z/
Kent MI-
1231 PM EDT Mon Sep 13 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHERN KENT COUNTY WILL
EXPIRE AT 1230 PM EDT...
                
The storm which prompted the warning has weakened below severe
levels, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  

However, hail to 0.50 to 0.75 of an inch is still possible, along 
with gusty winds to 45 mph, frequent lightning and heavy rain.

LAT...LON 4302 8531 4277 8531 4277 8578 4300 8579
TIME...MOT...LOC 1629Z 273DEG 48KT 4280 8541 

$$

DUKE

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 13, 3:05 AM EDTSmall Craft AdvisoryGRR56 hr
Sep 13, 3:08 AM EDTBeach Hazards StatementGRRAllegan, Mason, Muskegon, Oceana, Ottawa, Van Buren50 hr
Sep 13, 4:52 AM EDTSpecial Marine WarningGRR113 min
Sep 13, 10:33 AM EDTSpecial Marine WarningGRR87 min
Sep 13, 10:56 AM EDTSpecial Weather StatementGRRKent, Muskegon, Newaygo, Ottawa64 min
Sep 13, 12:36 PM EDTSpecial Weather StatementGRRClinton, Eaton, Gratiot, Ingham, Ionia84 min
Sep 13, 1:18 PM EDTSevere Thunderstorm WarningGRRIngham16 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.