Alert archive / Michigan / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 140
The Storm Prediction Center issued this severe thunderstorm watch at Apr 20, 2003, 3:25 PM EDT for 22 counties in Michigan. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 20, 2003, 3:25 PM EDT (19:25 UTC)
- Expired
- Apr 20, 2003, 8:00 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 22 counties
Branch County, MI, Calhoun County, MI, Clinton County, MI, Eaton County, MI, Genesee County, MI, Hillsdale County, MI, Ingham County, MI, Jackson County, MI, Lapeer County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Monroe County, MI, Oakland County, MI, Saginaw County, MI, Saint Clair County, MI, Saint Joseph County, MI, Sanilac County, MI, Shiawassee County, MI, Tuscola County, MI, Washtenaw County, MI, Wayne County, MI
The radar
The Detroit radar (KDTX), 58 km from the middle of the area, began a volume at 19:28 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
7 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 20, 3:35 PM EDT | Severe Thunderstorm Warning | DTX | Macomb | 40 min |
| Apr 20, 3:54 PM EDT | Severe Thunderstorm Warning | DTX | Saint Clair | 51 min |
| Apr 20, 4:37 PM EDT | Severe Thunderstorm Warning | DTX | Livingston, Washtenaw | 53 min |
| Apr 20, 5:07 PM EDT | Severe Thunderstorm Warning | DTX | Oakland | 38 min |
| Apr 20, 5:35 PM EDT | Severe Thunderstorm Warning | DTX | Lapeer | 55 min |
| Apr 20, 5:43 PM EDT | Severe Thunderstorm Warning | DTX | Macomb, Oakland, Wayne | 47 min |
| Apr 20, 5:57 PM EDT | Severe Thunderstorm Warning | DTX | Saint Clair, Sanilac | 48 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, 7.4 hours before the alert went out and 62 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
- 41 J/kg
- Mixed-layer CIN
- -164 J/kg
- Mixed-layer LCL
- 1190 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 177 m²/s²
- 0-3 km storm-relative helicity
- 171 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 |
|---|---|---|---|---|
| Apr 20, 3:09 PM EDT | Mesoscale Discussion | SPC | Barry, Bay, Branch, Calhoun, Cass, Clinton and 26 more | 3 hr |
| Apr 20, 3:34 PM EDT | Mesoscale Discussion | SPC | Barry, Bay, Branch, Calhoun, Cass, Clinton and 26 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Michigan, 2003Every severe thunderstorm watch in 2003
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.