Alert archive / Michigan / Mesoscale Discussions in 2015

Mesoscale Discussion 270

April 10, 201521 counties in Michigan

The Storm Prediction Center issued this mesoscale discussion at Apr 10, 2015, 12:56 AM EDT for 21 counties in Michigan. It was in force for 94 min.

The area

The outline as issued.

The facts

Issued: Apr 10, 2015, 12:56 AM EDT (04:56 UTC)
Expired: Apr 10, 2015, 2:30 AM EDT
In force: 94 min
Issued by: the Storm Prediction Center

All 21 counties

Barry County, MI, Bay County, MI, Calhoun County, MI, Clinton County, MI, Eaton County, MI, Genesee County, MI, Gratiot County, MI, Ingham County, MI, Ionia County, MI, Jackson County, MI, Kalamazoo County, MI, Kent County, MI, Lapeer County, MI, Livingston County, MI, Midland County, MI, Montcalm County, MI, Oakland County, MI, Saginaw County, MI, Shiawassee County, MI, Tuscola County, MI, Van Buren County, MI

The radar

The Grand Rapids radar (KGRR), 61 km from the middle of the area, began a volume at 04:57 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.

The nearest sounding before it

Detroit, MI (KDTX), launched 00:00Z, 4.9 hours before the alert went out and 113 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 171 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 682 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 332 m²/s²
0-3 km storm-relative helicity: 337 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.9

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 9, 9:27 PM EDT	Mesoscale Discussion	SPC	Allegan, Barry, Branch, Calhoun, Cass, Clare and 21 more	93 min
Apr 9, 9:55 PM EDT	Severe Thunderstorm Watch	SPC	Allegan, Barry, Berrien, Branch, Calhoun, Cass and 22 more	5 hr
Apr 10, 2:54 AM EDT	Mesoscale Discussion	SPC	Hillsdale, Ingham, Jackson, Lapeer, Lenawee, Livingston and 5 more	66 min

Nearby

Mesoscale Discussions in Michigan, 2015 Every mesoscale discussion in 2015

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.