Alert archive / Mississippi / Mesoscale Discussions in 2020

Mesoscale Discussion 355

April 12, 202016 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 1:40 PM CDT for 16 counties in Mississippi. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Apr 12, 2020, 1:40 PM CDT (18:40 UTC)
Expired: Apr 12, 2020, 3:15 PM CDT
In force: 95 min
Issued by: the Storm Prediction Center

Counties Attala County, MS, Choctaw County, MS, Hinds County, MS, Holmes County, MS, Kemper County, MS, Lauderdale County, MS, Leake County, MS, Madison County, MS, Neshoba County, MS, Newton County, MS, Noxubee County, MS, Oktibbeha County, MS, Rankin County, MS, Scott County, MS, Winston County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 70 km from the middle of the area, began a volume at 18:43 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 110Apr 12, 4:40 PM CDT

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 6.7 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: 323 J/kg
Mixed-layer CIN: -279 J/kg
Mixed-layer LCL: 625 m above ground
0-6 km bulk shear: 51 kt
0-1 km storm-relative helicity: 379 m²/s²
0-3 km storm-relative helicity: 562 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.2

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
Apr 12, 7:18 AM CDT	Mesoscale Discussion	SPC	Warren	87 min
Apr 12, 10:24 AM CDT	Mesoscale Discussion	SPC	Adams, Attala, Calhoun, Carroll, Chickasaw, Choctaw and 42 more	96 min
Apr 12, 10:41 AM CDT	Tornado Watch PDS	SPC	Adams, Attala, Bolivar, Calhoun, Carroll, Chickasaw and 47 more	10 hr
Apr 12, 12:03 PM CDT	Mesoscale Discussion	SPC	Attala, Carroll, Hinds, Holmes, Humphreys, Issaquena and 6 more	87 min
Apr 12, 1:02 PM CDT	Mesoscale Discussion	SPC	Amite, Hancock, Lamar, Marion, Pearl River, Pike and 1 more	118 min
Apr 12, 1:24 PM CDT	Tornado Watch	SPC	Amite, Covington, Forrest, Franklin, Hancock, Harrison and 11 more	9 hr
Apr 12, 3:38 PM CDT	Mesoscale Discussion	SPC	Copiah, Covington, Jasper, Jefferson Davis, Kemper, Lauderdale and 14 more	97 min
Apr 12, 3:52 PM CDT	Mesoscale Discussion	SPC	Covington, Jefferson Davis, Jones, Marion	23 min
Apr 12, 3:53 PM CDT	Mesoscale Discussion	SPC	Greene, Perry, Wayne	97 min
Apr 12, 4:26 PM CDT	Mesoscale Discussion	SPC	Covington, Jasper, Jones	34 min
Apr 12, 4:38 PM CDT	Tornado Watch PDS	SPC	George, Greene, Perry, Stone, Wayne	7 hr
Apr 12, 4:54 PM CDT	Mesoscale Discussion	SPC	Clarke, Covington, Jasper, Jefferson Davis, Jones, Wayne	66 min
Apr 12, 5:27 PM CDT	Mesoscale Discussion	SPC	Amite, Pike, Walthall	63 min
Apr 12, 5:44 PM CDT	Mesoscale Discussion	SPC	Attala, Calhoun, Carroll, Chickasaw, Choctaw, Clay and 23 more	91 min

Nearby

Mesoscale Discussions in Mississippi, 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.