Alert archive / Mississippi / Mesoscale Discussions in 2020

Mesoscale Discussion 1074

July 1, 202012 counties in Mississippi; 4 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Jul 1, 2020, 4:46 PM CDT for 12 counties in Mississippi; 4 counties in Tennessee. It was in force for 119 min.

The area

The outline as issued.

The facts

Issued: Jul 1, 2020, 4:46 PM CDT (21:46 UTC)
Expired: Jul 1, 2020, 6:45 PM CDT
In force: 119 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

Counties Alcorn County, MS, Benton County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Marshall County, MS, Monroe County, MS, Pontotoc County, MS, Prentiss County, MS, Tippah County, MS, Tishomingo County, MS, Union County, MS, Fayette County, TN, Hardeman County, TN, McNairy County, TN, Shelby County, TN

The radar

The Memphis radar (KNQA), 89 km from the middle of the area, began a volume at 21:46 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

Little Rock, AR (KLZK), launched 12:00Z, 9.8 hours before the alert went out and 71 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: 1981 J/kg
Mixed-layer CIN: -109 J/kg
Mixed-layer LCL: 621 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 61 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.

Issued	Product	Office	Counties	Lasted
Jul 1, 2:54 PM CDT	Mesoscale Discussion	SPC	Benton, DeSoto, Marshall, Panola, Tate, Tippah and 1 more	66 min

Nearby

Mesoscale Discussions in Mississippi, 2020 Mesoscale Discussions in Tennessee, 2020 Every 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.