Alert archive / Michigan / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 1, NWS Grand Rapids, MI

April 10, 2021Kent County, Ottawa County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Apr 10, 2021, 4:26 PM EDT for Kent County, Ottawa County, Michigan. It was in force for 27 min. 2 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
Apr 10, 2021, 4:26 PM EDT (20:26 UTC)
Expired
Apr 10, 2021, 4:53 PM EDT
In force
27 min
Issued by
NWS Grand Rapids, MI
Area
Storm-based polygon
Tornado
Possible
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 20:27 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
Apr 10, 4:38 PM EDTHAIL 0.252 Sw East Grand Rapids, MI
Apr 10, 4:58 PM EDTTSTM WND GST 422 Ese Kent City, MI

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, 8.4 hours before the alert went out and 200 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 2021-04-10Temperature 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 2021-04-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 128 square meters per square second.1939587897Sfc1 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
1320 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
128 m²/s²
0-3 km storm-relative helicity
225 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

514 
WUUS53 KGRR 102026
SVRGRR
MIC081-139-102115-
/O.NEW.KGRR.SV.W.0001.210410T2026Z-210410T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
426 PM EDT Sat Apr 10 2021

The National Weather Service in Grand Rapids has issued a

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

* Until 515 PM EDT.

* At 426 PM EDT, a severe thunderstorm was located near Wyoming, or 7
  miles south of Grand Rapids, moving north at 40 mph.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Grand Rapids...        Wyoming...             Kentwood...
  Walker...              Grandville...          East Grand Rapids...
  Coopersville...        Sparta...              Jenison...
  Allendale...           Conklin...             Wright...
  Kent City...           Dutton...              Cutlerville...
  Crockery Lake...       Lamont...              Comstock Park...
  Grand Valley...        Marne...               

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 4312 8599 4312 8591 4321 8591 4320 8579
      4322 8579 4322 8569 4283 8553 4283 8577
      4310 8600
TIME...MOT...LOC 2026Z 160DEG 36KT 4285 8568 

TORNADO...POSSIBLE
HAIL...<.75IN
WIND...60MPH
 
$$

CAS
2 follow-up statements
186 
WWUS53 KGRR 102040
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
440 PM EDT Sat Apr 10 2021

MIC081-139-102115-
/O.CON.KGRR.SV.W.0001.000000T0000Z-210410T2115Z/
Kent MI-Ottawa MI-
440 PM EDT Sat Apr 10 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM EDT
FOR WESTERN KENT AND NORTHEASTERN OTTAWA COUNTIES...

At 440 PM EDT, a severe thunderstorm was located over Grand Rapids, 
or near Walker, moving north at 40 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Grand Rapids...        Wyoming...             Kentwood...
Walker...              Grandville...          East Grand Rapids...
Coopersville...        Sparta...              Jenison...
Allendale...           Conklin...             Wright...
Kent City...           Crockery Lake...       Lamont...
Comstock Park...       Grand Valley...        Marne...
Northview...           

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4312 8599 4312 8591 4321 8591 4320 8579
      4322 8579 4322 8569 4288 8555 4288 8581
      4310 8600
TIME...MOT...LOC 2039Z 160DEG 36KT 4298 8574 

HAIL...<.75IN
WIND...60MPH
 
$$

CAS
721 
WWUS53 KGRR 102053
SVSGRR

Severe Weather Statement
National Weather Service Grand Rapids MI
453 PM EDT Sat Apr 10 2021

MIC081-139-102102-
/O.CAN.KGRR.SV.W.0001.000000T0000Z-210410T2115Z/
Kent MI-Ottawa MI-
453 PM EDT Sat Apr 10 2021

...THE SEVERE THUNDERSTORM WARNING FOR WESTERN KENT AND NORTHEASTERN
OTTAWA COUNTIES 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, cloud 
to ground lightning is still possible with this thunderstorm.

LAT...LON 4312 8599 4312 8591 4321 8591 4320 8579
      4322 8579 4322 8569 4288 8555 4288 8581
      4310 8600
TIME...MOT...LOC 2050Z 160DEG 36KT 4311 8580 

$$

CAS

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 10, 2:38 PM EDTSpecial Weather StatementGRRKalamazoo, Van Buren52 min
Apr 10, 3:18 PM EDTSpecial Weather StatementGRRCalhoun, Jackson42 min
Apr 10, 3:25 PM EDTSpecial Weather StatementGRRAllegan, Barry, Eaton, Ingham65 min
Apr 10, 4:11 PM EDTSpecial Weather StatementGRRKent, Ottawa49 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.