Alert archive / Michigan / Severe Thunderstorm Watches in 2007
Severe Thunderstorm Watch 689
The Storm Prediction Center issued this severe thunderstorm watch at Sep 25, 2007, 2:59 PM CDT for 4 counties in Illinois; 17 counties in Indiana; 49 counties in Michigan. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Sep 25, 2007, 2:59 PM CDT (19:59 UTC)
- Expired
- Sep 25, 2007, 9:00 PM CDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 70 counties
Ford County, IL, Iroquois County, IL, Kankakee County, IL, Will County, IL, Benton County, IN, Elkhart County, IN, Fulton County, IN, Jasper County, IN, Kosciusko County, IN, LaGrange County, IN, Lake County, IN, LaPorte County, IN, Marshall County, IN, Newton County, IN, Noble County, IN, Porter County, IN, Pulaski County, IN, Saint Joseph County, IN, Starke County, IN, Steuben County, IN, White County, IN, Alcona County, MI, Allegan County, MI, Alpena County, MI, Arenac County, MI, Barry County, MI, Bay County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Clare County, MI, Clinton County, MI, Eaton County, MI, Genesee County, MI, Gladwin County, MI, Gratiot County, MI, Hillsdale County, MI, Huron County, MI, Ingham County, MI, Ionia County, MI, Iosco County, MI, Isabella County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Lapeer County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Mecosta County, MI, Midland County, MI, Monroe County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oakland County, MI, Ogemaw County, MI, Oscoda County, MI, Ottawa County, MI, Roscommon County, MI, Saginaw County, MI, Saint Clair County, MI, Saint Joseph County, MI, Sanilac County, MI, Shiawassee County, MI, Tuscola County, MI, Van Buren County, MI, Washtenaw County, MI, Wayne County, MI
The radar
The Grand Rapids radar (KGRR), 19 km from the middle of the area, began a volume at 20:02 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 70%
- One or more gusts of 65 knots or more
- 20%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 20%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
15 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 25, 3:29 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Will | 28 min |
| Sep 25, 3:56 PM CDT | Severe Thunderstorm Warning | GRR | Allegan, Barry | 64 min |
| Sep 25, 3:59 PM CDT | Severe Thunderstorm Warning | GRR | Gratiot, Montcalm | 31 min |
| Sep 25, 4:18 PM CDT | Severe Thunderstorm Warning | LOT | Lake, Porter | 45 min |
| Sep 25, 4:41 PM CDT | Severe Thunderstorm Warning | IWX | LaPorte | 61 min |
| Sep 25, 4:56 PM CDT | Severe Thunderstorm Warning | GRR | Allegan | 49 min |
| Sep 25, 5:05 PM CDT | Severe Thunderstorm Warning | DTX | Bay, Saginaw | 39 min |
| Sep 25, 5:16 PM CDT | Severe Thunderstorm Warning | GRR | Ottawa | 23 min |
| Sep 25, 5:21 PM CDT | Severe Thunderstorm Warning | GRR | Clinton | 24 min |
| Sep 25, 5:31 PM CDT | Severe Thunderstorm Warning | GRR | Kent | 47 min |
| Sep 25, 5:41 PM CDT | Severe Thunderstorm Warning | GRR | Barry | 46 min |
| Sep 25, 5:50 PM CDT | Severe Thunderstorm Warning | DTX | Shiawassee | 42 min |
| Sep 25, 6:00 PM CDT | Severe Thunderstorm Warning | GRR | Ionia | 45 min |
| Sep 25, 6:14 PM CDT | Severe Thunderstorm Warning | GRR | Clinton | 46 min |
| Sep 25, 6:16 PM CDT | Severe Thunderstorm Warning | DTX | Genesee | 59 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Detroit, MI (KDTX), launched 12:00Z, 8.0 hours before the alert went out and 182 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
- 199 J/kg
- Mixed-layer CIN
- -107 J/kg
- Mixed-layer LCL
- 1026 m above ground
- 0-6 km bulk shear
- 34 kt
- 0-1 km storm-relative helicity
- -8 m²/s²
- 0-3 km storm-relative helicity
- 31 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 25, 1:36 PM CDT | Mesoscale Discussion | SPC | Cook, DuPage, Ford, Grundy, Iroquois, Kane and 8 more | 84 min |
| Sep 24, 7:37 PM CDT | Mesoscale Discussion | SPC | Baraga, Dickinson, Iron | 83 min |
Nearby
Severe Thunderstorm Watches in Michigan, 2007Severe Thunderstorm Watches in Indiana, 2007Severe Thunderstorm Watches in Illinois, 2007Every severe thunderstorm watch in 2007
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.