Alert archive / Minnesota / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 96, NWS Duluth, MN

July 21, 2020Pine County, Minnesota; Burnett County, Wisconsin

NWS Duluth, MN issued this severe thunderstorm warning at Jul 21, 2020, 4:16 PM CDT for Pine County, Minnesota; Burnett County, Wisconsin. It was in force for 59 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 21, 2020, 4:16 PM CDT (21:16 UTC)
Expired: Jul 21, 2020, 5:15 PM CDT
In force: 59 min
Issued by: NWS Duluth, MN
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Pine County, MN, Burnett County, WI

The radar

The Duluth radar (KDLH), 98 km from the middle of the area, began a volume at 21:20 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

Minneapolis, MN (KMPX), launched 12:00Z, 9.3 hours before the alert went out and 151 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: 148 J/kg
Mixed-layer CIN: -84 J/kg
Mixed-layer LCL: 1094 m above ground
0-6 km bulk shear: 52 kt
0-1 km storm-relative helicity: 159 m²/s²
0-3 km storm-relative helicity: 214 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.7

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 Duluth, MN wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 21, 3:47 PM CDT, 29 minutes earlier.

Area forecast discussion, Jul 21, 3:47 PM CDT, 29 minutes before

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Hazardous weather outlook, Jul 21, 3:51 AM CDT, 12 hours 25 minutes before

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In the hours before

Special weather statement, Jul 21, 12:10 PM CDT, 4 hours 6 minutes before

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Local storm report, Jul 21, 12:24 PM CDT, 3 hours 52 minutes before

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Local storm report, Jul 21, 12:59 PM CDT, 3 hours 17 minutes before

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Local storm report, Jul 21, 1:11 PM CDT, 3 hours 5 minutes before

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Special weather statement, Jul 21, 4:04 PM CDT, 12 minutes before

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Local storm report, Jul 21, 4:09 PM CDT, 7 minutes before

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The office that day

Everything else NWS Duluth, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 21, 3:50 AM CDT	Beach Hazards Statement	DLH	Carlton, Saint Louis	17 hr
Jul 21, 3:53 AM CDT	Small Craft Advisory	DLH		20 hr
Jul 21, 4:04 PM CDT	Special Weather Statement	DLH	Burnett	26 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2020 Severe Thunderstorm Warnings in Wisconsin, 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; radar from the NEXRAD Level II archive.