Alert archive / Michigan / Severe Thunderstorm Warnings in 2021
Severe Thunderstorm Warning 55, NWS Grand Rapids, MI
NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 12, 2021, 6:15 AM EDT for Calhoun County, Jackson County, Michigan. It was in force for 45 min. 8 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 12, 2021, 6:15 AM EDT (10:15 UTC)
- Expired
- Aug 12, 2021, 7:00 AM EDT
- In force
- 45 min
- Issued by
- NWS Grand Rapids, MI
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Calhoun County, MI, Jackson County, MI
The radar
The Detroit radar (KDTX), 88 km from the middle of the area, began a volume at 10:18 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 12, 6:20 AM EDT | TSTM WND DMG | 1 Nne Moscow, MI | CORRECTS PREVIOUS TSTM WND DMG REPORT FROM 1 NNE MOSCOW. DELAYED REPORT. 3 FT DIAMETER TREE SNAPPED, LARGE 1-2 FT DIAMETER LIMB DOWNED. A POWER POLE WAS ALSO SNAPPED AND LEANING ON A HOUSE. DAMAGE WAS ALONG MOSHERVILLE RD AT TWO SEPARATE RESIDENCES NEAR BIBBIN |
| Aug 12, 6:25 AM EDT | TSTM WND DMG | 2 E Hanover, MI | ABOUT 10 TREES UPROOTED AND 10 TREES OF VARIOUS SIZES SNAPPED ALONG A 5 MILE STRETCH OF MOSCOW ROAD NORTH OF HILLSDALE COUNTY LINE. |
| Aug 12, 6:42 AM EDT | TSTM WND DMG | 2 Sse Norvell, MI | MULTIPLE LARGE HEALTHY TREES SNAPPED OR UPROOTED. |
| Aug 12, 6:49 AM EDT | TSTM WND DMG | 2 W Napoleon, MI | MULTIPLE TREES DOWN ALL ALONG AND ACROSS STONY LAKE ROAD. |
| Aug 12, 6:50 AM EDT | TSTM WND DMG | 1 Sse Brooklyn, MI | TREES DOWN ACROSS M-50 IN BROOKLYN. |
| Aug 12, 6:52 AM EDT | TSTM WND DMG | Hanover, MI | TREES AND WIRES BLOCKING HANOVER ROAD IN HANOVER MI. |
| Aug 12, 6:55 AM EDT | TSTM WND DMG | 2 Wsw Brooklyn, MI | TREES AND WIRES DOWN ALONG CEMENT CITY ROAD BLOCKING ROADWAY. |
| Aug 12, 6:56 AM EDT | TSTM WND GST 51 | 3 Ene Sandstone, MI | ASOS STATION KJXN JACKSON COUNTY-REYNOLDS FIELD AIRPORT. |
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, 10.3 hours before the alert went out and 92 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.
389 WUUS53 KGRR 121015 SVRGRR MIC025-075-121100- /O.NEW.KGRR.SV.W.0055.210812T1015Z-210812T1100Z/ BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Grand Rapids MI 615 AM EDT Thu Aug 12 2021 The National Weather Service in Grand Rapids has issued a * Severe Thunderstorm Warning for... Southeastern Calhoun County in south central Michigan... Jackson County in south central Michigan... * Until 700 AM EDT. * At 610 AM EDT, a severe thunderstorm was located near Quincy, or 7 miles northeast of Coldwater, moving northeast at 65 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Jackson... Homer... Brooklyn... Grass Lake... Vandercook Lake... Leoni... Spring Arbor... Napoleon... Sandstone... Norvell... Pulaski... Concord... Horton... Hanover... Oak Point... Sunset Beach... Michigan Center... PRECAUTIONARY/PREPAREDNESS ACTIONS... This storm has a history of wind gusts over 60 mph. For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4207 8414 4207 8499 4243 8415 4242 8413 TIME...MOT...LOC 1013Z 246DEG 57KT 4201 8488 HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...<.75 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...60 MPH $$ OSTUNO
2 follow-up statements
377
WWUS53 KGRR 121045
SVSGRR
Severe Weather Statement
National Weather Service Grand Rapids MI
645 AM EDT Thu Aug 12 2021
MIC025-121053-
/O.CAN.KGRR.SV.W.0055.000000T0000Z-210812T1100Z/
Calhoun MI-
645 AM EDT Thu Aug 12 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CALHOUN COUNTY IS
CANCELLED...
The severe thunderstorm which prompted the warning has moved out of
the warned area. Therefore, the warning has been cancelled.
LAT...LON 4207 8414 4207 8470 4212 8468 4242 8413
TIME...MOT...LOC 1043Z 246DEG 57KT 4221 8428
$$
MIC075-121100-
/O.CON.KGRR.SV.W.0055.000000T0000Z-210812T1100Z/
Jackson MI-
645 AM EDT Thu Aug 12 2021
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 700 AM EDT
FOR SOUTHEASTERN JACKSON COUNTY...
At 643 AM EDT, a severe thunderstorm was located near Grass Lake, or
6 miles east of Jackson, moving northeast at 65 mph.
HAZARD...60 mph wind gusts.
SOURCE...Radar indicated.
IMPACT...Expect damage to roofs, siding, and trees.
Locations impacted include...
Jackson... Brooklyn... Grass Lake...
Vandercook Lake... Leoni... Napoleon...
Norvell... Pulaski... Horton...
Hanover... Oak Point... Sunset Beach...
Michigan Center...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This storm has a history of producing wind gusts over 60 mph. For
your protection move to an interior room on the lowest floor of a
building.
&&
LAT...LON 4207 8414 4207 8470 4212 8468 4242 8413
TIME...MOT...LOC 1043Z 246DEG 57KT 4221 8428
HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH
$$
OSTUNO877
WWUS53 KGRR 121101
SVSGRR
Severe Weather Statement
National Weather Service Grand Rapids MI
701 AM EDT Thu Aug 12 2021
MIC075-121111-
/O.EXP.KGRR.SV.W.0055.000000T0000Z-210812T1100Z/
Jackson MI-
701 AM EDT Thu Aug 12 2021
...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN JACKSON COUNTY
HAS EXPIRED...
The storm which prompted the warning has moved out of the area.
Therefore, the warning has been allowed to expire.
LAT...LON 4207 8414 4207 8470 4212 8468 4242 8413
TIME...MOT...LOC 1101Z 246DEG 57KT 4232 8395
$$
OSTUNOThe office that day
Everything else NWS Grand Rapids, MI issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 11, 8:19 PM EDT | Severe Thunderstorm Warning | GRR | Allegan, Ottawa | 72 min |
| 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, 6:23 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.