Alert archive / South Dakota / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 96, NWS Aberdeen, SD

July 20, 2019Dewey County, Potter County, Walworth County, South Dakota

NWS Aberdeen, SD issued this severe thunderstorm warning at Jul 20, 2019, 1:36 AM MDT for Dewey County, Potter County, Walworth County, South Dakota. 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: Jul 20, 2019, 1:36 AM MDT (07:36 UTC)
Expired: Jul 20, 2019, 2:15 AM MDT
In force: 39 min
Issued by: NWS Aberdeen, SD
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Dewey County, SD, Potter County, SD, Walworth County, SD

The radar

The Aberdeen radar (KABR), 149 km from the middle of the area, began a volume at 07:37 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
Jul 19, 10:48 PM MDT	Severe Thunderstorm Watch	SPC	5 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 7.6 hours before the alert went out and 152 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: 769 J/kg
Mixed-layer CIN: -200 J/kg
Mixed-layer LCL: 1190 m above ground
0-6 km bulk shear: 70 kt
0-1 km storm-relative helicity: -86 m²/s²
0-3 km storm-relative helicity: 118 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -4.3

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 Aberdeen, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 19, 5:30 PM MDT, 8 hours 6 minutes earlier.

Area forecast discussion, Jul 19, 5:30 PM MDT, 8 hours 6 minutes before

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Hazardous weather outlook, Jul 19, 1:33 PM MDT, 12 hours 3 minutes before

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The office that day

Everything else NWS Aberdeen, SD issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 20, 12:59 AM MDT	Severe Thunderstorm Warning	ABR	Dewey	46 min
Jul 20, 1:43 AM MDT	Severe Thunderstorm Warning	ABR	Dewey, Potter, Walworth	62 min
Jul 20, 2:52 AM MDT	Severe Thunderstorm Warning	ABR	Faulk, Potter	38 min
Jul 20, 2:57 AM MDT	Severe Thunderstorm Warning	ABR	Faulk, Hand, Hyde, Potter, Sully	48 min
Jul 20, 3:34 AM MDT	Severe Thunderstorm Warning	ABR	Buffalo, Hand, Hughes, Hyde, Jones, Lyman and 2 more	56 min
Jul 20, 4:22 AM MDT	Severe Thunderstorm Warning	ABR	Hand, Spink	38 min
Jul 20, 4:32 AM MDT	Severe Thunderstorm Warning	ABR	Buffalo, Hughes, Hyde, Lyman, Stanley	58 min
Jul 20, 4:53 AM MDT	Severe Thunderstorm Warning	ABR	Clark, Spink	52 min
Jul 20, 5:22 AM MDT	Severe Thunderstorm Warning	ABR	Clark, Codington, Day, Hamlin	38 min
Jul 20, 5:29 AM MDT	Severe Thunderstorm Warning	ABR	Buffalo, Hand, Hyde	31 min
Jul 20, 5:44 AM MDT	Severe Thunderstorm Warning	ABR	Clark, Codington, Day, Deuel, Grant, Hamlin	61 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 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.