Alert archive / Michigan / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 52, NWS Detroit, MI

October 20, 20184 counties in Michigan

NWS Detroit, MI issued this severe thunderstorm warning at Oct 20, 2018, 1:55 PM EDT for 4 counties in Michigan. It was in force for 39 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: Oct 20, 2018, 1:55 PM EDT (17:55 UTC)
Expired: Oct 20, 2018, 2:34 PM EDT
In force: 39 min
Issued by: NWS Detroit, MI
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Livingston County, MI, Oakland County, MI, Washtenaw County, MI, Wayne County, MI

The radar

The Detroit radar (KDTX), 30 km from the middle of the area, began a volume at 17:54 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 12:00Z, 5.9 hours before the alert went out and 33 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: 5 J/kg
Mixed-layer CIN: -27 J/kg
Mixed-layer LCL: 921 m above ground
0-6 km bulk shear: 87 kt
0-1 km storm-relative helicity: -50 m²/s²
0-3 km storm-relative helicity: -16 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 Oct 20, 1:29 PM EDT, 26 minutes earlier.

Area forecast discussion, Oct 20, 1:29 PM EDT, 26 minutes before

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Hazardous weather outlook, Oct 20, 12:24 PM EDT, 1 hour 31 minutes before

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In the hours before

Special weather statement, Oct 20, 12:45 PM EDT, 1 hour 10 minutes before

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Special weather statement, Oct 20, 1:04 PM EDT, 51 minutes before

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Special weather statement, Oct 20, 1:15 PM EDT, 40 minutes before

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Special weather statement, Oct 20, 1:23 PM EDT, 32 minutes before

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Special weather statement, Oct 20, 1:47 PM EDT, 8 minutes before

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Local storm report, Oct 20, 1:49 PM EDT, 6 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
Oct 20, 3:40 AM EDT	Small Craft Advisory	DTX		36 hr
Oct 20, 11:09 AM EDT	Lakeshore Flood Advisory	DTX	Huron	16 hr
Oct 20, 11:46 AM EDT	Wind Advisory	DTX	Lenawee, Livingston, Macomb, Monroe, Oakland, Saint Clair and 2 more	9 hr
Oct 20, 12:33 PM EDT	Special Weather Statement	DTX	Saint Clair	42 min
Oct 20, 12:45 PM EDT	Special Weather Statement	DTX	Tuscola	30 min
Oct 20, 1:00 PM EDT	Special Marine Warning	DTX		103 min
Oct 20, 1:04 PM EDT	Special Weather Statement	DTX	Huron	26 min
Oct 20, 1:15 PM EDT	Special Weather Statement	DTX	Tuscola	30 min
Oct 20, 1:23 PM EDT	Special Weather Statement	DTX	Genesee, Livingston	37 min
Oct 20, 1:39 PM EDT	Severe Thunderstorm Warning	DTX	Genesee, Lapeer, Livingston, Macomb, Oakland	55 min
Oct 20, 1:47 PM EDT	Special Weather Statement	DTX	Livingston, Washtenaw, Wayne	58 min
Oct 20, 2:16 PM EDT	Special Weather Statement	DTX	Macomb, Saint Clair	59 min
Oct 20, 2:20 PM EDT	Severe Thunderstorm Warning	DTX	Lapeer, Macomb, Oakland, Saint Clair, Wayne	38 min
Oct 20, 3:31 PM EDT	Severe Thunderstorm Warning	DTX	Washtenaw	42 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2018 Every severe thunderstorm warning in 2018

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.