Alert archive / South Dakota / Mesoscale Discussions in 2020

Mesoscale Discussion 1085

July 2, 20208 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 2, 2020, 5:16 PM MDT for 8 counties in South Dakota. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued
Jul 2, 2020, 5:16 PM MDT (23:16 UTC)
Expired
Jul 2, 2020, 7:15 PM MDT
In force
119 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 322

Counties Dewey County, SD, Haakon County, SD, Jackson County, SD, Meade County, SD, Pennington County, SD, Perkins County, SD, Stanley County, SD, Ziebach County, SD

The radar

The Rapid City radar (KUDX), 82 km from the middle of the area, began a volume at 23:16 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

Rapid City, SD (KUNR), launched 12:00Z, 11.3 hours before the alert went out and 89 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-pSkew-T log-p diagram, Rapid City, SD at 12:00Z on 2020-07-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1543 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Rapid City, SD at 12:00Z on 2020-07-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 51 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
1543 J/kg
Mixed-layer CIN
-273 J/kg
Mixed-layer LCL
1698 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
51 m²/s²
0-3 km storm-relative helicity
35 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 2, 11:59 AM MDTMesoscale DiscussionSPCButte, Corson, Custer, Haakon, Jackson, Meade and 5 more91 min
Jul 2, 1:15 PM MDTSevere Thunderstorm WatchSPCBennett, Buffalo, Butte, Corson, Custer, Dewey and 17 more9 hr

Nearby

Mesoscale Discussions in South Dakota, 2020Every mesoscale discussion 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.