Alert archive / Michigan / Severe Thunderstorm Watches in 2002
Severe Thunderstorm Watch 680
The Storm Prediction Center issued this severe thunderstorm watch at Sep 10, 2002, 5:20 PM EDT for 12 counties in Michigan. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 10, 2002, 5:20 PM EDT (21:20 UTC)
- Expired
- Sep 10, 2002, 10:00 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
Counties Genesee County, MI, Lapeer County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Monroe County, MI, Oakland County, MI, Saint Clair County, MI, Sanilac County, MI, Tuscola County, MI, Washtenaw County, MI, Wayne County, MI
The radar
The Detroit radar (KDTX), 27 km from the middle of the area, began a volume at 21:23 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
2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 10, 5:47 PM EDT | Severe Thunderstorm Warning | DTX | Sanilac | 43 min |
| Sep 10, 7:45 PM EDT | Severe Thunderstorm Warning | DTX | Saint Clair | 45 min |
The nearest sounding before it
Detroit, MI (KDTX), launched 12:00Z, 9.3 hours before the alert went out and 30 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
- 512 J/kg
- Mixed-layer CIN
- -87 J/kg
- Mixed-layer LCL
- 1163 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- -12 m²/s²
- 0-3 km storm-relative helicity
- -23 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.3
The text
As transmitted, in the capitals the NWS used until 2016.
000 WWUS20 KWNS 102120 SEL0 SPC WW 102120 MIZ000-110200- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 680 STORM PREDICTION CENTER NORMAN OK 520 PM EDT TUE SEP 10 2002 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF SOUTHEAST LOWER MICHIGAN WESTERN LAKE ERIE SOUTHERN LAKE HURON EFFECTIVE THIS TUESDAY AFTERNOON AND EVENING FROM 520 PM UNTIL 1000 PM EDT. HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 35 STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH OF ANN ARBOR MICHIGAN TO 60 MILES NORTHEAST OF FLINT MICHIGAN. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES. DISCUSSION...THUNDERSTORMS WITH A THREAT OF DAMAGING WINDS AND LARGE HAIL WILL CONTINUE TO SPREAD EWD ACROSS SOUTHEAST LOWER MI THROUGH THE EARLY TO MID EVENING. STRONG UPPER TROUGH NOW APPROACHING THE AREA...COMBINED WITH SUFFICIENT CAPE AND SHEAR... SHOULD SUSTAIN A THREAT OF SEVERE THUNDERSTORMS. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 27030. ...EVANS 414,0842 433,0833 433,0821 414,0830
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.