Alert archive / Michigan / Severe Thunderstorm Watches in 2013
Severe Thunderstorm Watch 504
The Storm Prediction Center issued this severe thunderstorm watch at Aug 30, 2013, 2:07 PM CDT for 20 counties in Illinois; 33 counties in Michigan; 15 counties in Wisconsin. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 30, 2013, 2:07 PM CDT (19:07 UTC)
- Expired
- Aug 30, 2013, 9:00 PM CDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 68 counties
Boone County, IL, Bureau County, IL, Carroll County, IL, Cook County, IL, DeKalb County, IL, DuPage County, IL, Grundy County, IL, Jo Daviess County, IL, Kane County, IL, Kendall County, IL, Lake County, IL, LaSalle County, IL, Lee County, IL, McHenry County, IL, Ogle County, IL, Putnam County, IL, Stephenson County, IL, Whiteside County, IL, Will County, IL, Winnebago County, IL, Allegan County, MI, Barry County, MI, Bay County, MI, Berrien County, MI, Branch County, MI, Calhoun County, MI, Cass County, MI, Clinton County, MI, Eaton County, MI, Genesee County, MI, Gratiot County, MI, Hillsdale County, MI, Huron County, MI, Ingham County, MI, Ionia County, MI, Isabella County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Lapeer County, MI, Mecosta County, MI, Midland County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Ottawa County, MI, Saginaw County, MI, Saint Joseph County, MI, Sanilac County, MI, Shiawassee County, MI, Tuscola County, MI, Van Buren County, MI, Dane County, WI, Dodge County, WI, Grant County, WI, Green County, WI, Iowa County, WI, Jefferson County, WI, Kenosha County, WI, Lafayette County, WI, Milwaukee County, WI, Ozaukee County, WI, Racine County, WI, Rock County, WI, Walworth County, WI, Washington County, WI, Waukesha County, WI
The radar
The Grand Rapids radar (KGRR), 119 km from the middle of the area, began a volume at 19:10 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
- 30%
- One or more gusts of 65 knots or more
- 5%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
12 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 2:29 PM CDT | Severe Thunderstorm Warning | MKX | Dodge, Milwaukee, Ozaukee, Washington, Waukesha | 46 min |
| Aug 30, 3:02 PM CDT | Severe Thunderstorm Warning | MKX | Milwaukee, Racine, Washington, Waukesha | 43 min |
| Aug 30, 3:40 PM CDT | Severe Thunderstorm Warning | MKX | Jefferson, Kenosha, Milwaukee, Racine, Rock, Walworth and 1 more | 50 min |
| Aug 30, 4:16 PM CDT | Severe Thunderstorm Warning | LOT | Lake, McHenry | 59 min |
| Aug 30, 4:18 PM CDT | Severe Thunderstorm Warning | MKX | Kenosha, Racine, Rock, Walworth | 42 min |
| Aug 30, 4:43 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DeKalb, DuPage, Kane, Lake, McHenry | 62 min |
| Aug 30, 4:51 PM CDT | Severe Thunderstorm Warning | MKX | Walworth | 39 min |
| Aug 30, 5:24 PM CDT | Severe Thunderstorm Warning | LOT | Boone, DeKalb, Kane, McHenry | 66 min |
| Aug 30, 5:40 PM CDT | Severe Thunderstorm Warning | LOT | Cook, DeKalb, DuPage, Kane, Kendall, Will | 65 min |
| Aug 30, 6:25 PM CDT | Severe Thunderstorm Warning | LOT | Cook, Kankakee, Will | 65 min |
| Aug 30, 7:00 PM CDT | Severe Thunderstorm Warning | GRR | Van Buren | 60 min |
| Aug 30, 7:32 PM CDT | Severe Thunderstorm Warning | DVN | Stephenson | 43 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
Green Bay/Straub, WI (KGRB), launched 12:00Z, 7.1 hours before the alert went out and 209 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
- 1815 J/kg
- Mixed-layer CIN
- -70 J/kg
- Mixed-layer LCL
- 723 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 218 m²/s²
- 0-3 km storm-relative helicity
- 235 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 12.5
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 30, 12:24 PM CDT | Mesoscale Discussion | SPC | Boone, Lake, McHenry, Stephenson, Winnebago | 2 hr |
| Aug 30, 5:14 PM CDT | Mesoscale Discussion | SPC | Boone, Bureau, Carroll, Cook, DeKalb, DuPage and 14 more | 61 min |
| Aug 29, 7:30 PM CDT | Mesoscale Discussion | SPC | Gogebic | 90 min |
| Aug 29, 11:57 PM CDT | Mesoscale Discussion | SPC | Gogebic | 93 min |
| Aug 29, 8:20 PM CDT | Tornado Watch | SPC | Ashland, Barron, Bayfield, Brown, Burnett, Calumet and 30 more | 5 hr |
Nearby
Severe Thunderstorm Watches in Michigan, 2013Severe Thunderstorm Watches in Illinois, 2013Severe Thunderstorm Watches in Wisconsin, 2013Every severe thunderstorm watch in 2013
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.