Alert archive / Michigan / Severe Thunderstorm Watches in 2012

Severe Thunderstorm Watch 467

July 5, 201217 counties in Michigan

The Storm Prediction Center issued this severe thunderstorm watch at Jul 5, 2012, 3:04 AM EDT for 17 counties in Michigan. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued
Jul 5, 2012, 3:04 AM EDT (07:04 UTC)
Expired
Jul 5, 2012, 6:10 AM EDT
In force
3 hr
Issued by
the Storm Prediction Center
Largest hail expected
1 in
Strongest gust expected
60 kt

Counties Barry County, MI, Calhoun County, MI, Eaton County, MI, Genesee County, MI, Ingham County, MI, Ionia 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, Shiawassee County, MI, Washtenaw County, MI, Wayne County, MI

The radar

The Detroit radar (KDTX), 34 km from the middle of the area, began a volume at 07:05 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
20%
One or more EF2 to EF5 tornadoes
5%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
10%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
70%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jul 5, 3:16 AM EDTSevere Thunderstorm WarningDTXSaginaw, Shiawassee66 min
Jul 5, 3:43 AM EDTSevere Thunderstorm WarningDTXGenesee, Oakland, Saginaw, Tuscola66 min
Jul 5, 3:50 AM EDTSevere Thunderstorm WarningDTXLivingston70 min
Jul 5, 3:50 AM EDTSevere Thunderstorm WarningGRRIngham25 min
Jul 5, 4:10 AM EDTSevere Thunderstorm WarningDTXLapeer, Oakland65 min
Jul 5, 4:27 AM EDTSevere Thunderstorm WarningDTXWashtenaw, Wayne63 min
Jul 5, 4:35 AM EDTSevere Thunderstorm WarningDTXMacomb, Saint Clair70 min
Jul 5, 5:29 AM EDTSevere Thunderstorm WarningDTXMonroe24 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 00:00Z, 7.1 hours before the alert went out and 37 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, Detroit, MI at 00:00Z on 2012-07-05Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4748 joules per kilogram.LCLEL10008507005003002001001 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, Detroit, MI at 00:00Z on 2012-07-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 75 square meters per square second.1939Sfc1 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
4748 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
1268 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
75 m²/s²
0-3 km storm-relative helicity
119 m²/s²
Significant tornado parameter
1.4
Supercell composite
9.5

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 5, 2:57 AM EDTMesoscale DiscussionSPCSteuben63 min
Jul 5, 3:27 PM EDTMesoscale DiscussionSPCAdams, Allen, DeKalb, Steuben, Wells93 min
Jul 5, 5:58 PM EDTMesoscale DiscussionSPCAdams, Allen, Blackford, Boone, Carroll, Cass and 40 more92 min
Jul 4, 11:54 PM EDTMesoscale DiscussionSPCClare, Gratiot, Ionia, Isabella, Kent, Lake and 11 more96 min
Jul 5, 4:12 AM EDTMesoscale DiscussionSPCGenesee, Ingham, Jackson, Lenawee, Livingston, Macomb and 4 more93 min

Nearby

Severe Thunderstorm Watches in Michigan, 2012Every severe thunderstorm watch in 2012

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.