Alert archive / Michigan / Special Weather Statements in 2021

Special Weather Statement, NWS Grand Rapids, MI

August 7, 2021Muskegon County, Oceana County, Ottawa County, Michigan

NWS Grand Rapids, MI issued this special weather statement at Aug 7, 2021, 11:37 PM EDT for Muskegon County, Oceana County, Ottawa County, Michigan. It was in force for 83 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 7, 2021, 11:37 PM EDT (03:37 UTC)
Expired
Aug 8, 2021, 1:00 AM EDT
In force
83 min
Issued by
NWS Grand Rapids, MI
Hail
0.00 in
Wind
40

Counties Muskegon County, MI, Oceana County, MI, Ottawa County, MI

The radar

The Grand Rapids radar (KGRR), 62 km from the middle of the area, began a volume at 03:39 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.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 3.6 hours before the alert went out and 209 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, Green Bay/Straub, WI at 00:00Z on 2021-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 22 joules per kilogram.LCLLFCEL10008507005003002001001 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, Green Bay/Straub, WI at 00:00Z on 2021-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 106 square meters per square second.193958Sfc1 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
22 J/kg
Mixed-layer CIN
-122 J/kg
Mixed-layer LCL
1055 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
106 m²/s²
0-3 km storm-relative helicity
275 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

411 
WWUS83 KGRR 080337
SPSGRR

Special Weather Statement
National Weather Service Grand Rapids MI
1137 PM EDT Sat Aug 7 2021
 
MIZ043-050-056-080500-
Oceana MI-Muskegon MI-Ottawa MI-
1137 PM EDT Sat Aug 7 2021

...Strong thunderstorms will impact portions of Ottawa, Muskegon and
Oceana Counties through 100 AM EDT...

At 1136 PM EDT, Doppler radar was tracking strong thunderstorms along
a line extending from 7 miles southwest of Shelby to 13 miles
southwest of Grand Haven. Movement was east at 30 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Locations impacted include...
Muskegon, Holland, Grand Haven, Hart, Walker, Shelby, Muskegon
Heights, Hudsonville, Zeeland, Coopersville, Roosevelt Park, North
Muskegon, Ferrysburg, Whitehall, Montague, Spring Lake, Lakewood
Club, Ravenna, Fruitport and Hesperia.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

Persons in campgrounds should consider seeking sturdy shelter until
these storms pass.

&&

LAT...LON 4382 8643 4382 8604 4330 8604 4329 8579
      4277 8578 4277 8620 4278 8614 4279 8611
      4278 8621 4309 8625 4362 8654
TIME...MOT...LOC 0336Z 280DEG 27KT 4354 8648 4295 8646 

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

$$

TJT

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 11:20 PM EDTSpecial Marine WarningGRR55 min
Aug 8, 12:09 AM EDTSpecial Weather StatementGRRKent, Mecosta, Montcalm, Newaygo2 hr
Aug 8, 12:55 AM EDTSpecial Marine WarningGRR110 min
Aug 8, 4:05 AM EDTBeach Hazards StatementGRRMason, Muskegon, Oceana, Ottawa22 hr

Nearby

Special Weather Statements in Michigan, 2021Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.