Alert archive / Michigan / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 22, NWS Marquette, MI

July 18, 2020Dickinson County, Iron County, Michigan

NWS Marquette, MI issued this severe thunderstorm warning at Jul 18, 2020, 5:17 AM CDT for Dickinson County, Iron County, Michigan. It was in force for 43 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: Jul 18, 2020, 5:17 AM CDT (10:17 UTC)
Expired: Jul 18, 2020, 6:00 AM CDT
In force: 43 min
Issued by: NWS Marquette, MI
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Dickinson County, MI, Iron County, MI

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 00:00Z, 10.3 hours before the alert went out and 181 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: 748 J/kg
Mixed-layer CIN: -65 J/kg
Mixed-layer LCL: 1554 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: 60 m²/s²
0-3 km storm-relative helicity: 108 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.3

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 Marquette, MI wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 18, 2:57 AM CDT, 2 hours 20 minutes earlier.

Area forecast discussion, Jul 18, 2:57 AM CDT, 2 hours 20 minutes before

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Hazardous weather outlook, Jul 18, 3:58 AM CDT, 1 hour 19 minutes before

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In the hours before

Special weather statement, Jul 18, 3:29 AM CDT, 1 hour 48 minutes before

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Local storm report, Jul 18, 3:59 AM CDT, 1 hour 18 minutes before

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Special weather statement, Jul 18, 4:11 AM CDT, 1 hour 6 minutes before

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Local storm report, Jul 18, 4:26 AM CDT, 51 minutes before

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Special weather statement, Jul 18, 5:09 AM CDT, 8 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 18, 2:31 AM CDT	Beach Hazards Statement	MQT	Schoolcraft	18 hr
Jul 18, 3:29 AM CDT	Special Weather Statement	MQT	Gogebic, Ontonagon	46 min
Jul 18, 4:11 AM CDT	Special Weather Statement	MQT	Baraga, Houghton, Iron, Ontonagon	64 min
Jul 18, 5:09 AM CDT	Special Weather Statement	MQT	Baraga, Delta, Dickinson, Keweenaw, Marquette	66 min
Jul 18, 5:24 AM CDT	Special Marine Warning	MQT		66 min
Jul 18, 6:16 AM CDT	Special Weather Statement	MQT	Alger, Delta, Marquette, Menominee	44 min
Jul 18, 6:57 AM CDT	Special Weather Statement	MQT	Alger, Delta, Schoolcraft	48 min
Jul 18, 7:21 AM CDT	Special Marine Warning	MQT		54 min
Jul 18, 7:44 AM CDT	Special Weather Statement	MQT	Alger, Delta, Luce, Schoolcraft	61 min
Jul 18, 8:49 AM CDT	Special Weather Statement	MQT	Luce	41 min

Nearby

Severe Thunderstorm Warnings in Michigan, 2020 Every severe thunderstorm warning in 2020

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.