Alert archive / Michigan / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 52, NWS Grand Rapids, MI
NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 11, 2021, 8:19 PM EDT for Allegan County, Ottawa County, Michigan. It was in force for 72 min. 3 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 11, 2021, 8:19 PM EDT (00:19 UTC)
- Expired
- Aug 11, 2021, 9:31 PM EDT
- In force
- 72 min
- Issued by
- NWS Grand Rapids, MI
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Allegan County, MI, Ottawa County, MI
The radar
The Grand Rapids radar (KGRR), 45 km from the middle of the area, began a volume at 00:17 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 11, 8:50 PM EDT | TSTM WND DMG | 2 W Drenthe, MI | SNAPPED UTILITY POLE...RELAYED VIA SOCIAL MEDIA. TIME ESTIMATED FROM RADAR. |
| Aug 11, 9:01 PM EDT | TORNADO | 2 E Burnips, MI | EF0 TORNADO MOVED THROUGH NORTHERN PORTIONS OF ALLEGAN COUNTY FOR ABOUT 3 MILES. MAXIMUM PATH WIDTH WAS ABOUT 100 YARDS. ONE OUTBUILDING WAS DESTROYED NEAR 26TH STREET WITH METAL ROOFING DEBRIS SCATTERED ALONG THE PATH. A LARGE IRRIGATION STRUCTURE WAS ALSO KN |
| Aug 11, 9:12 PM EDT | TSTM WND GST 54 | 1 Wnw Drenthe, MI | CMU FIELD RESEARCH PROJECT. |
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 00:00Z, 0.3 hours before the alert went out and 219 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.
- Mixed-layer CAPE
- 12 J/kg
- Mixed-layer CIN
- -458 J/kg
- Mixed-layer LCL
- 1474 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 243 m²/s²
- 0-3 km storm-relative helicity
- 373 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
735
WUUS53 KGRR 120019
SVRGRR
MIC005-139-120145-
/O.NEW.KGRR.SV.W.0052.210812T0019Z-210812T0145Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Grand Rapids MI
819 PM EDT Wed Aug 11 2021
The National Weather Service in Grand Rapids has issued a
* Severe Thunderstorm Warning for...
Northwestern Allegan County in southwestern Michigan...
Ottawa County in southwestern Michigan...
* Until 945 PM EDT.
* At 818 PM EDT, severe thunderstorms were located along a line
extending from just offshore of Ferrysburg to 25 miles west of
Holland, moving east at 35 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
* Locations impacted include...
Holland... Grand Haven... Hudsonville...
Zeeland... Coopersville... Ferrysburg...
Spring Lake... Saugatuck... Beechwood...
Jenison... Allendale... Hamilton...
Wright... Douglas... Port Sheldon...
Lamont... Drenthe... Olive Center...
Eastmanville... Marne...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4311 8626 4312 8579 4264 8578 4265 8622
4270 8620 4290 8621
TIME...MOT...LOC 0018Z 281DEG 29KT 4309 8630 4278 8669
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
MEADE3 follow-up statements
591
WWUS53 KGRR 120046
SVSGRR
Severe Weather Statement
National Weather Service Grand Rapids MI
846 PM EDT Wed Aug 11 2021
MIC005-139-120145-
/O.CON.KGRR.SV.W.0052.000000T0000Z-210812T0145Z/
Allegan MI-Ottawa MI-
846 PM EDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR NORTHWESTERN ALLEGAN AND OTTAWA COUNTIES...
At 845 PM EDT, severe thunderstorms were located along a line
extending from Coopersville to Holland, moving east at 50 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
Locations in the path of this storm include... Coopersville,
Allendale, Zeeland, Hudsonville, Jenison, Drenthe, Jamestown, and
Burnips.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4311 8626 4312 8579 4264 8578 4265 8622
4270 8620 4290 8621
TIME...MOT...LOC 0043Z 276DEG 46KT 4305 8603 4278 8616
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
CAS697
WWUS53 KGRR 120100
SVSGRR
Severe Weather Statement
National Weather Service Grand Rapids MI
900 PM EDT Wed Aug 11 2021
MIC005-139-120145-
/O.CON.KGRR.SV.W.0052.000000T0000Z-210812T0145Z/
Allegan MI-Ottawa MI-
900 PM EDT Wed Aug 11 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 945 PM EDT
FOR NORTHWESTERN ALLEGAN AND SOUTHEASTERN OTTAWA COUNTIES...
At 900 PM EDT, severe thunderstorms were located along a line
extending from near Jenison to 8 miles southeast of Zeeland, moving
east at 50 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Holland... Hudsonville... Saugatuck...
Jenison... Hamilton... Douglas...
Burnips... Jamestown... Vriesland...
Drenthe... Overisel...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
For your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4266 8621 4280 8599 4294 8588 4292 8579
4264 8578 4265 8622
TIME...MOT...LOC 0100Z 291DEG 43KT 4291 8580 4272 8589
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
CAS265
WWUS53 KGRR 120131
SVSGRR
Severe Weather Statement
National Weather Service Grand Rapids MI
931 PM EDT Wed Aug 11 2021
MIC005-139-120139-
/O.CAN.KGRR.SV.W.0052.000000T0000Z-210812T0145Z/
Allegan MI-Ottawa MI-
931 PM EDT Wed Aug 11 2021
...THE SEVERE THUNDERSTORM WARNING FOR NORTHWESTERN ALLEGAN AND
SOUTHEASTERN OTTAWA COUNTIES IS CANCELLED...
The storms which prompted the warning have weakened below severe
limits, and no longer pose an immediate threat to life or property.
Therefore, the warning has been cancelled. However, gusty winds to
40 mph, frequent lightning strikes, and heavy rain are still
possible with these thunderstorms.
A Severe Thunderstorm Watch remains in effect until 300 AM EDT for
southwestern Michigan.
LAT...LON 4266 8621 4280 8599 4294 8588 4292 8579
4264 8578 4265 8622
TIME...MOT...LOC 0127Z 281DEG 29KT 4287 8551 4268 8560
$$
CASThe office that day
Everything else NWS Grand Rapids, MI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 8:26 PM EDT | Special Marine Warning | GRR | 90 min | |
| Aug 11, 8:56 PM EDT | Severe Thunderstorm Warning | GRR | Allegan, Barry, Kent | 49 min |
| Aug 11, 9:30 PM EDT | Severe Thunderstorm Warning | GRR | Barry, Clinton, Eaton, Ionia | 45 min |
| Aug 11, 10:40 PM EDT | Special Weather Statement | GRR | Calhoun, Jackson | 50 min |
| Aug 12, 12:01 AM EDT | Special Weather Statement | GRR | Allegan | 59 min |
| Aug 12, 12:32 AM EDT | Special Weather Statement | GRR | Kent | 28 min |
| Aug 12, 12:56 AM EDT | Areal Flood Advisory | GRR | Calhoun, Ingham, Jackson | 5 hr |
| Aug 12, 1:21 AM EDT | Areal Flood Advisory | GRR | Clinton, Eaton, Ingham | 2 hr |
| Aug 12, 3:38 AM EDT | Areal Flood Warning | GRR | Clinton, Eaton, Ingham | 5 hr |
| Aug 12, 4:39 AM EDT | Special Weather Statement | GRR | Eaton, Ingham | 66 min |
| Aug 12, 6:09 AM EDT | Special Weather Statement | GRR | Calhoun | 66 min |
| Aug 12, 6:15 AM EDT | Severe Thunderstorm Warning | GRR | Calhoun, Jackson | 45 min |
| Aug 12, 6:23 AM EDT | Areal Flood Warning | GRR | Calhoun, Ingham, Jackson | 4 hr |
| Aug 12, 8:39 AM EDT | Areal Flood Advisory | GRR | Clinton, Eaton, Ingham | 111 min |
| Aug 12, 10:30 AM EDT | Areal Flood Advisory | GRR | Calhoun, Ingham, Jackson | 2 hr |
| Aug 12, 11:06 AM EDT | River Flood Warning | GRR | Ingham | 36 hr |
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.