Alert archive / Michigan / Severe Thunderstorm Watches in 2014

Severe Thunderstorm Watch 151

May 12, 201426 counties in Michigan

The Storm Prediction Center issued this severe thunderstorm watch at May 12, 2014, 2:41 PM EDT for 26 counties in Michigan. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
May 12, 2014, 2:41 PM EDT (18:41 UTC)
Expired
May 12, 2014, 9:33 PM EDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
1.5 in
Strongest gust expected
60 kt
All 26 counties

Allegan County, MI, Barry County, MI, Calhoun County, MI, Clinton County, MI, Eaton County, MI, Gratiot County, MI, Ingham County, MI, Ionia County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Lenawee County, MI, Livingston County, MI, Macomb County, MI, Mecosta County, MI, Monroe County, MI, Montcalm County, MI, Muskegon County, MI, Newaygo County, MI, Oakland County, MI, Oceana County, MI, Ottawa County, MI, Shiawassee County, MI, Van Buren County, MI, Washtenaw County, MI, Wayne County, MI

The radar

The Grand Rapids radar (KGRR), 38 km from the middle of the area, began a volume at 18:44 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
10%
Ten or more severe hail reports
30%
One or more hailstones of 2 inches or more
10%
Six or more combined severe hail and wind reports
60%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
May 12, 2:43 PM EDTSevere Thunderstorm WarningGRRIonia, Isabella, Kent, Mecosta, Montcalm, Muskegon and 3 more62 min
May 12, 2:46 PM EDTSevere Thunderstorm WarningGRRIngham, Jackson29 min
May 12, 3:02 PM EDTSevere Thunderstorm WarningDTXLivingston, Washtenaw58 min
May 12, 3:18 PM EDTTornado WarningDTXLivingston, Washtenaw57 min
May 12, 3:26 PM EDTSevere Thunderstorm WarningGRRIonia49 min
May 12, 3:40 PM EDTSevere Thunderstorm WarningGRRIngham, Jackson50 min
May 12, 3:48 PM EDTTornado WarningDTXWashtenaw57 min
May 12, 3:55 PM EDTSevere Thunderstorm WarningGRRBarry, Eaton65 min
May 12, 4:05 PM EDTSevere Thunderstorm WarningDTXLenawee, Monroe55 min
May 12, 4:14 PM EDTTornado WarningDTXLivingston, Washtenaw46 min
May 12, 4:28 PM EDTTornado WarningDTXMonroe, Wayne62 min
May 12, 4:33 PM EDTFlash Flood WarningDTXGenesee, Livingston, Oakland, Shiawassee6 hr
May 12, 4:55 PM EDTTornado WarningDTXMonroe65 min
May 12, 5:09 PM EDTSevere Thunderstorm WarningGRRIngham51 min
May 12, 5:35 PM EDTSevere Thunderstorm WarningDTXLivingston55 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, 6.7 hours before the alert went out and 136 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 12:00Z on 2014-05-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 12:00Z on 2014-05-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 126 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1025 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
126 m²/s²
0-3 km storm-relative helicity
117 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 12, 2:29 PM EDTMesoscale DiscussionSPCAllegan, Barry, Branch, Calhoun, Cass, Clinton and 16 more91 min
May 12, 4:44 PM EDTMesoscale DiscussionSPCAllegan, Barry, Calhoun, Clinton, Eaton, Genesee and 17 more61 min
May 12, 7:05 PM EDTMesoscale DiscussionSPCAllegan, Barry, Calhoun, Clinton, Eaton, Genesee and 17 more55 min

Nearby

Severe Thunderstorm Watches in Michigan, 2014Every severe thunderstorm watch in 2014

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.