Alert archive / Michigan / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 74, NWS Detroit, MI

September 11, 2019Shiawassee County, Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Sep 11, 2019, 7:48 PM EDT for Shiawassee County, Michigan. It was in force for 40 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Sep 11, 2019, 7:48 PM EDT (23:48 UTC)
Expired: Sep 11, 2019, 8:28 PM EDT
In force: 40 min
Issued by: NWS Detroit, MI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Shiawassee County, MI

The radar

The Detroit radar (KDTX), 62 km from the middle of the area, began a volume at 23:47 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 11, 2:31 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Detroit, MI (KDTX), launched 12:00Z, 11.8 hours before the alert went out and 64 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: 345 J/kg
Mixed-layer CIN: -110 J/kg
Mixed-layer LCL: 1098 m above ground
0-6 km bulk shear: 26 kt
0-1 km storm-relative helicity: 7 m²/s²
0-3 km storm-relative helicity: 58 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Detroit, MI wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 11, 4:04 PM EDT, 3 hours 44 minutes earlier.

Area forecast discussion, Sep 11, 4:04 PM EDT, 3 hours 44 minutes before

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Hazardous weather outlook, Sep 11, 2:55 PM EDT, 4 hours 53 minutes before

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In the hours before

Local storm report, Sep 11, 5:30 PM EDT, 2 hours 18 minutes before

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Special weather statement, Sep 11, 5:35 PM EDT, 2 hours 13 minutes before

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Special weather statement, Sep 11, 6:11 PM EDT, 1 hour 37 minutes before

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Local storm report, Sep 11, 6:35 PM EDT, 1 hour 13 minutes before

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Local storm report, Sep 11, 6:50 PM EDT, 58 minutes before

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Special weather statement, Sep 11, 7:36 PM EDT, 12 minutes before

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The office that day

Everything else NWS Detroit, MI issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 10, 8:15 PM EDT	Special Weather Statement	DTX	Huron	60 min
Sep 10, 8:36 PM EDT	Tornado Warning	DTX	Tuscola	24 min
Sep 10, 8:52 PM EDT	Tornado Warning	DTX	Sanilac	41 min
Sep 10, 9:09 PM EDT	Special Weather Statement	DTX	Lapeer	36 min
Sep 10, 9:13 PM EDT	Special Marine Warning	DTX		62 min
Sep 10, 9:57 PM EDT	Special Weather Statement	DTX	Lapeer	63 min
Sep 11, 3:43 AM EDT	Small Craft Advisory	DTX		66 hr
Sep 11, 1:48 PM EDT	Special Weather Statement	DTX	Lenawee, Washtenaw	57 min
Sep 11, 2:13 PM EDT	Severe Thunderstorm Warning	DTX	Livingston, Oakland, Washtenaw, Wayne	33 min
Sep 11, 2:37 PM EDT	Special Weather Statement	DTX	Monroe	38 min
Sep 11, 2:41 PM EDT	Special Weather Statement	DTX	Genesee	64 min
Sep 11, 2:56 PM EDT	Special Weather Statement	DTX	Saint Clair	49 min
Sep 11, 3:00 PM EDT	Special Weather Statement	DTX	Macomb, Oakland	60 min
Sep 11, 3:10 PM EDT	Severe Thunderstorm Warning	DTX	Saint Clair	35 min
Sep 11, 3:12 PM EDT	Special Marine Warning	DTX		52 min
Sep 11, 3:14 PM EDT	Special Weather Statement	DTX	Lapeer	61 min
Sep 11, 3:17 PM EDT	Special Weather Statement	DTX	Huron, Sanilac, Tuscola	88 min
Sep 11, 3:21 PM EDT	Severe Thunderstorm Warning	DTX	Lapeer, Sanilac	54 min
Sep 11, 3:50 PM EDT	Special Weather Statement	DTX	Lapeer	55 min
Sep 11, 3:56 PM EDT	Severe Thunderstorm Warning	DTX	Lapeer, Oakland	20 min
Sep 11, 5:15 PM EDT	Areal Flood Advisory	DTX	Macomb, Oakland, Washtenaw, Wayne	3 hr
Sep 11, 5:26 PM EDT	Special Weather Statement	DTX	Washtenaw	64 min
Sep 11, 5:35 PM EDT	Special Weather Statement	DTX	Genesee, Shiawassee	55 min
Sep 11, 6:11 PM EDT	Special Weather Statement	DTX	Saint Clair	64 min
Sep 11, 7:36 PM EDT	Special Weather Statement	DTX	Livingston, Oakland	54 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2019 Every severe thunderstorm warning in 2019

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.