Alert archive / Mississippi / Mesoscale Discussions in 2021

Mesoscale Discussion 872

June 7, 202111 counties in Arkansas; Jackson Parish, Lincoln Parish, Union Parish, Louisiana; 14 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jun 7, 2021, 5:23 PM CDT for 11 counties in Arkansas; Jackson Parish, Lincoln Parish, Union Parish, Louisiana; 14 counties in Mississippi. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued
Jun 7, 2021, 5:23 PM CDT (22:23 UTC)
Expired
Jun 7, 2021, 6:30 PM CDT
In force
67 min
Issued by
the Storm Prediction Center
Concerning
Severe thunderstorm watch 243
All 28 counties

Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Cleveland County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Jefferson County, AR, Lincoln County, AR, Union County, AR, Jackson Parish, LA, Lincoln Parish, LA, Union Parish, LA, Attala County, MS, Bolivar County, MS, Carroll County, MS, Choctaw County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Leflore County, MS, Montgomery County, MS, Sunflower County, MS, Tallahatchie County, MS, Washington County, MS, Webster County, MS, Winston County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 165 km from the middle of the area, began a volume at 22:24 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

Jackson, MS (KJAN), launched 12:00Z, 10.4 hours before the alert went out and 155 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, Jackson, MS at 12:00Z on 2021-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 723 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, Jackson, MS at 12:00Z on 2021-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 square meters per square second.193958Sfc1 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
723 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
564 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.7

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
Jun 7, 12:32 PM CDTSevere Thunderstorm WatchSPCArkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 21 more6 hr
Jun 7, 2:16 PM CDTMesoscale DiscussionSPCClark, Dallas, Garland, Grant, Hempstead, Hot Spring and 8 more119 min
Jun 7, 3:08 PM CDTMesoscale DiscussionSPCAshley, Bradley, Columbia, Lafayette, Union2 hr
Jun 7, 5:09 PM CDTSevere Thunderstorm WatchSPCAshley, Chicot3 hr

Nearby

Mesoscale Discussions in Mississippi, 2021Mesoscale Discussions in Arkansas, 2021Mesoscale Discussions in Louisiana, 2021Every mesoscale discussion in 2021

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.