Alert archive / South Dakota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 385, NWS Rapid City, SD

August 18, 2011Meade County, Perkins County, South Dakota

NWS Rapid City, SD issued this severe thunderstorm warning at Aug 18, 2011, 3:34 PM MDT for Meade County, Perkins County, South Dakota. It was in force for 56 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: Aug 18, 2011, 3:34 PM MDT (21:34 UTC)
Expired: Aug 18, 2011, 4:30 PM MDT
In force: 56 min
Issued by: NWS Rapid City, SD
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Meade County, SD, Perkins County, SD

The radar

The Rapid City radar (KUDX), 102 km from the middle of the area, began a volume at 21:36 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

Bismarck Municip, ND (KBIS), launched 12:00Z, 9.6 hours before the alert went out and 243 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: 1365 J/kg
Mixed-layer CIN: -162 J/kg
Mixed-layer LCL: 1577 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 76 m²/s²
0-3 km storm-relative helicity: 96 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 Rapid City, SD wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 18, 2:50 PM MDT, 44 minutes earlier.

Area forecast discussion, Aug 18, 2:50 PM MDT, 44 minutes before

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Hazardous weather outlook, Aug 18, 6:48 AM MDT, 8 hours 46 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 17, 6:06 PM MDT	Severe Thunderstorm Warning	UNR	Mellette, Todd, Tripp	54 min
Aug 17, 6:11 PM MDT	Severe Thunderstorm Warning	UNR	Mellette	49 min
Aug 17, 6:34 PM MDT	Tornado Warning	UNR	Todd, Tripp	32 min
Aug 17, 6:55 PM MDT	Severe Thunderstorm Warning	UNR	Mellette, Todd	65 min
Aug 17, 7:01 PM MDT	Severe Thunderstorm Warning	UNR	Todd, Tripp	59 min
Aug 17, 7:31 PM MDT	Severe Thunderstorm Warning	UNR	Todd, Tripp	59 min
Aug 17, 7:58 PM MDT	Severe Thunderstorm Warning	UNR	Tripp	44 min
Aug 18, 3:40 PM MDT	Severe Thunderstorm Warning	UNR	Pennington	65 min
Aug 18, 3:55 PM MDT	Severe Thunderstorm Warning	UNR	Meade	38 min
Aug 18, 4:06 PM MDT	Severe Thunderstorm Warning	UNR	Meade, Perkins, Ziebach	54 min
Aug 18, 4:20 PM MDT	Severe Thunderstorm Warning	UNR	Bennett, Jackson	55 min
Aug 18, 5:07 PM MDT	Severe Thunderstorm Warning	UNR	Bennett	53 min

Nearby

Severe Thunderstorm Warnings in South Dakota, 2011 Every severe thunderstorm warning in 2011

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.