There were numerous reports of large hail and damaging severe thunderstorm wind gusts on September 7th. Wind gusts reached close to 70 mph in some areas and hail up to two and a half inches in diameter was reported.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GRR wrote it up.
There were numerous reports of large hail and damaging severe thunderstorm wind gusts on September 7th. Wind gusts reached close to 70 mph in some areas and hail up to two and a half inches in diameter was reported.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Grand Rapids, MI wrote its last area forecast discussion before the first event at Sep 7, 9:15 AM EST, 2 hours 45 minutes earlier.
Area Forecast Discussion
National Weather Service Grand Rapids MI
1015 AM EDT Tue Sep 7 2021
LATEST UPDATE...
Update
.SYNOPSIS...
Issued at 328 AM EDT Tue Sep 7 2021
- Upper Troughing and Severe Threat today followed by
deamplification to quasi-zonal flow regime
&&
.UPDATE...
Issued at 1015 AM EDT Tue Sep 7 2021
There are currently 2 lines of thunderstorms heading this way.
The first line, which currently is from near Manistee to Gaylord
is expected to head east and not impact much of our CWA, as there
already an outflow boundary ahead of it. A second line of storms,
which based on LSRs from GRB, there has been baseball to tennis
ball size hail will be the primary line of storms. The mid level
lapse rate this afternoon is over 7c so large hail is more than
possible. The near unidirectional wind with height favors
straight line wind damage. The latest guidance still shows 1500
j/kg mix layer cape this afternoon and the low level jet still is
forecast to strengthen this afternoon as it moves across our CWA.
Based on all of this I expect strong to severe storms over most of
our CWA this afternoon. Storms will be moving east southeast
around 45 mph to 50 mph, so even with heavy rain from the storms,
significant flooding is not expected from these storms.
Timing still suggests some storms on our NW CWA already but the
main squall line should be there around 1-2 pm, reach this area in
the 4 pm to 6 pm time frame and the Jackson area in the 6 pm to 10
pm time frame.
&&
.DISCUSSION...(Today through next Monday)
Issued at 328 AM EDT Tue Sep 7 2021
Slight Risk of severe weather for this afternoon and evening with
strong, unidirectional shear profiles indicating storm type will
be linear with bowing line segments bringing primarily downburst
wind threat but also QLCS tornado possibility. Tall skinny CAPE
through the hail growth region suggests any updrafts taller than
30 kft could have large hail threat as well.
Timing of the storms from blend of forecast guidance suggests
arrival time at or before 18Z across the far northwest forecast
area near Ludington and Manistee with the line of storms sagging
southeast and reaching Grands Rapids and Lansing around 20Z and
Jackson by 23Z. The storms should clear the forecast area by 03Z.
Environmental winds are strong with 40 to 50 knots near 5 kft AGL
and some of this could mix down in the cold air advection behind
the cold front, but more likely in any solid line of convection
along or ahead of the front. Dry adiabatic sub cloud layer could
also enhance downburst potential.
Scattered showers will persist on Wednesday under upper troughing
with diurnal and lake enhancement in the cool air. The trough
axis moves east with surface ridging moving in for Thursday with
temperatures tumbling into the 40s most places on Thursday night.
Quasi-zonal flow regime with embedded shortwave troughs follows
into the weekend with a chance of showers on Saturday and again
early next week.
&&
.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 715 AM EDT Tue Sep 7 2021
VFR conditions through 18Z then a line of thunderstorms will
bring areas of IFR this afternoon. Southwest wind will gust over
20 knots today with gusts over 40 knots possible in thunderstorms
this afternoon.
&&
.MARINE...
Issued at 328 AM EDT Tue Sep 7 2021
Gales are possible this afternoon along with thunderstorm
downburst winds over 40 knots. Hazardous conditions for small
craft may continue in the the strong northwest flow through
Wednesday. There may also be a possibility for waterspouts on
Wednesday.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement through Wednesday evening for MIZ037-043-
050-056-064-071.
LM...Small Craft Advisory until 8 PM EDT Wednesday for LMZ844>849.
&&
UPDATE...WDM
SYNOPSIS...Ostuno
DISCUSSION...Ostuno
AVIATION...Ostuno/WDM
MARINE...OstunoHazardous Weather Outlook National Weather Service Grand Rapids MI 334 AM EDT Tue Sep 7 2021 MIZ037>040-043>046-050>052-056>059-064>067-071>074-080745- Mason-Lake-Osceola-Clare-Oceana-Newaygo-Mecosta-Isabella-Muskegon- Montcalm-Gratiot-Ottawa-Kent-Ionia-Clinton-Allegan-Barry-Eaton- Ingham-Van Buren-Kalamazoo-Calhoun-Jackson- 334 AM EDT Tue Sep 7 2021 This hazardous weather outlook is for portions of southwest Lower Michigan. .DAY ONE...Today and Tonight There is a slight risk of severe weather this afternoon and evening. The main threat will be downburst wind damage. There is also the possibility of large hail and brief tornadoes. The storms will reach Muskegon around 2 pm, Lansing and Grand Rapids around 4 pm and Jackson around 6 pm. .DAYS TWO THROUGH SEVEN...Wednesday through Monday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation may be needed today. LMZ844>849-080745- St Joseph to South Haven MI-South Haven to Holland MI- Holland to Grand Haven MI-Grand Haven to Whitehall MI- Whitehall to Pentwater MI-Pentwater to Manistee MI- 334 AM EDT Tue Sep 7 2021 This hazardous weather outlook is for portions of southwest Lower Michigan. .DAY ONE...Today and Tonight Winds and waves will be hazardous to boaters and swimmers. Severe thunderstorms are possible this afternoon with winds over 50 knots. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Hazardous conditions for swimmers and boaters will continue into Wednesday. There may be a chance of waterspouts on Wednesday.
Special Weather Statement National Weather Service Grand Rapids MI 1218 PM EDT Tue Sep 7 2021 MIZ037>040-043>046-050>052-056>059-064>067-071>074-072000- Mason-Lake-Osceola-Clare-Oceana-Newaygo-Mecosta-Isabella-Muskegon- Montcalm-Gratiot-Ottawa-Kent-Ionia-Clinton-Allegan-Barry-Eaton- Ingham-Van Buren-Kalamazoo-Calhoun-Jackson- Including the cities of Ludington, Baldwin, Reed City, Clare, Hart, Fremont, Big Rapids, Mount Pleasant, Muskegon, Greenville, Alma, Grand Haven, Jenison, Grand Rapids, Ionia, St. Johns, Holland, Hastings, Charlotte, Lansing, South Haven, Kalamazoo, Battle Creek, and Jackson 1218 PM EDT Tue Sep 7 2021 ...Strong to Severe Storms Expected This Afternoon and Evening... A line of thunderstorms extending from Wisconsin through Northern Lower Michigan early this afternoon is expected to strengthen as it moves toward Central and Southern Lower Michigan later this afternoon and this evening. These thunderstorms will have the capability of winds 60+ mph, large hail over the size of a quarter, frequent lightning, and very heavy downpours. An isolated tornado will also be possible. The strongest storms will occur around 2-3 pm this afternoon toward the lakeshore, 5-6 pm around Grand Rapids, to around 7-9 pm this evening toward Jackson. The severe storms should exit the area by 10 pm. NJJ
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1259 PM EDT TUE SEP 7 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1248 PM NON-TSTM WND GST 1 NW NORTON SHORES 43.17N 86.26W
09/07/2021 M43 MPH MUSKEGON MI MESONET
MESONET STATION EW5817 NORTON SHORES.
&&
KENYONThe Grand Rapids radar (KGRR), 113 km away, was scanning. The volume nearest the first event began at 16:58 UTC.
9 thunderstorm wind, 4 hail. Local standard time, as filed.
Hail up to two and a half inches in diameter was reported across portions of Mason county.
Hail up to two and a half inches in diameter was reported.
Severe storms brought damaging wind gusts and hail up to one and three quarters inches in diameter.
Several trees and power lines were blown down near Lake George and Arthur Avenues and around Lake George.
Severe storms resulted in several reports of wind damage.
Several tree limbs were blown down near the CMU campus in Mt. Pleasant.
Widespread wind damage in the form of downed trees was reported near Hersey.
Wind damage was reported across portions of Kent county.
Multiple trees and power lines were blown down in Vestaburg.
A trained spotter reported one inch hail.
A 66 mph peak wind gust was reported at the Battle Creek airport ASOS and there were several reports of downed trees and power lines.
Several trees and tree limbs were blown down.
A few trees were blown down near Springport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Michigan in 2021Every state in 2021This day in weather historyWarnings in Michigan, September 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 977557, 977558, 977560, 977561, 977562, 977563, 977565, 977566, 977567, 977568, 977569, 977570, 977571.