Alert archive / Michigan / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 60, NWS Grand Rapids, MI

August 22, 2002Allegan County, Van Buren County, Michigan

NWS Grand Rapids, MI issued this severe thunderstorm warning at Aug 22, 2002, 12:06 AM EDT for Allegan County, Van Buren County, Michigan. It was in force for 54 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 22, 2002, 12:06 AM EDT (04:06 UTC)
Expired
Aug 22, 2002, 1:00 AM EDT
In force
54 min
Issued by
NWS Grand Rapids, MI
Area
Counties, with a storm outline in the text

Counties Allegan County, MI, Van Buren County, MI

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this severe thunderstorm warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The nearest sounding before it

Detroit, MI (KDTX), launched 00:00Z, 4.1 hours before the alert went out and 222 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 00:00Z on 2002-08-22Temperature 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°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Detroit, MI at 00:00Z on 2002-08-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1935 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
139 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Aug 21, 9:42 PM EDT, 2 hours 24 minutes earlier.

Area forecast discussion, Aug 21, 9:42 PM EDT, 2 hours 24 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
942 PM EDT WED AUG 21 2002

SURFACE LOW IS LOCATED NEAR LACROSSE WISCONSIN THIS EVENING...WITH A
WARM FRONTAL BOUNDARY EXTENDING EAST INTO NORTHERN LOWER MICHIGAN
(NORTH OF THE GRR CWA). WARM SOUTHERLY FLOW IS IN PLACE ACROSS
SOUTHWEST LOWER MICHIGAN...WITH DEW POINTS IN THE 70S ALONG THE LAKE
MICHIGAN COASTLINE. THE MOISTURE DECREASES ACROSS THE EASTERN
CWA...BUT THE CONVECTION SHOULD ATLEAST HOLD ITS OWN ACROSS LAKE
MICHIGAN INTO WESTERN LOWER. SITES IN EASTERN WISCONSIN HAVE GUSTED
TO NEAR 50 KNOTS IN THE LAST HOUR (ETB TO 41KTS AND UES TO 49KTS).
GIVEN AN INCREASING LOW LEVEL JET OVERHEAD...TO NEAR 50 KNOTS BY
06Z...DAMAGING WIND GUSTS ARE THE PRIMARY THREAT WITH THIS
CONVECTION AS IT MOVES EAST ACROSS THE LAKE. WILL CARRY CATEGORICAL
WORDING IN THE NORTH AND WEST...AND LEAVE THE CHANCE IN THE FAR
SOUTHEAST AS THE PRECIPITATION WILL BE MOVING INTO A MUCH LESS
FAVORABLE AIRMASS THERE. LOWS AND WINDS LOOK FINE IN THE GOING
FORECAST. HEAVY RAIN IS ALSO A THREAT WITH THE LOW LEVEL JET
POSITIONED OVERHEAD THROUGH THE NIGHT. REDEVELOPMENT IS ALREADY
OCCURRING TO THE WEST OF THE LINE OF STORMS COMING OUT OVER LAKE
MICHIGAN.

ZONES TO FOLLOW SHORTLY. SPECIAL MARINE WARNING JUST ISSUED FOR
GRAND HAVEN NORTHWARD TO MANISTEE.

.GRR...NONE.

DUKESHERER

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 21, 9:40 PM EDTSpecial Marine WarningGRR2 hr
Aug 21, 9:40 PM EDTSpecial Marine WarningGRR2 hr
Aug 21, 9:40 PM EDTSpecial Marine WarningGRR2 hr
Aug 21, 10:27 PM EDTSpecial Marine WarningGRR93 min
Aug 21, 10:27 PM EDTSpecial Marine WarningGRR93 min
Aug 21, 11:10 PM EDTSevere Thunderstorm WarningGRRMuskegon, Ottawa50 min
Aug 21, 11:58 PM EDTSpecial Marine WarningGRR47 min
Aug 21, 11:58 PM EDTSpecial Marine WarningGRR47 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2002Every severe thunderstorm warning in 2002

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.