Alert archive / Michigan / Severe Thunderstorm Watches in 2002

Severe Thunderstorm Watch 667

September 2, 200210 counties in Michigan

The Storm Prediction Center issued this severe thunderstorm watch at Sep 2, 2002, 4:30 PM EDT for 10 counties in Michigan. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Sep 2, 2002, 4:30 PM EDT (20:30 UTC)
Expired
Sep 2, 2002, 11:00 PM EDT
In force
7 hr
Issued by
the Storm Prediction Center

Counties Alger County, MI, Baraga County, MI, Dickinson County, MI, Gogebic County, MI, Houghton County, MI, Iron County, MI, Keweenaw County, MI, Marquette County, MI, Ontonagon County, MI, Schoolcraft County, MI

The radar

The Marquette radar (KMQT), 76 km from the middle of the area, began a volume at 20:30 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.

Warnings issued inside it

4 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Sep 2, 4:56 PM EDTSevere Thunderstorm WarningMQTGogebic, Ontonagon64 min
Sep 2, 6:41 PM EDTSevere Thunderstorm WarningMQTBaraga, Houghton64 min
Sep 2, 7:39 PM EDTSevere Thunderstorm WarningMQTMarquette51 min
Sep 2, 8:30 PM EDTSevere Thunderstorm WarningMQTMarquette60 min

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 8.5 hours before the alert went out and 270 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 12:00Z on 2002-09-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 joules per kilogram.LCLLFCEL10008507005003002001001 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, Green Bay/Straub, WI at 12:00Z on 2002-09-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 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
5 J/kg
Mixed-layer CIN
-474 J/kg
Mixed-layer LCL
1493 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
174 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 2, 5:45 PM EDTTornado WatchSPCDickinson5 hr

Nearby

Severe Thunderstorm Watches in Michigan, 2002Every severe thunderstorm watch 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; radar from the NEXRAD Level II archive.