Alert archive / Mississippi / Mesoscale Discussions in 2014

Mesoscale Discussion 434

April 27, 201416 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2014, 7:03 PM CDT for 16 counties in Mississippi. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued: Apr 27, 2014, 7:03 PM CDT (00:03 UTC)
Expired: Apr 27, 2014, 8:30 PM CDT
In force: 87 min
Issued by: the Storm Prediction Center

Counties Calhoun County, MS, Chickasaw County, MS, Clay County, MS, Grenada County, MS, Itawamba County, MS, Lafayette County, MS, Lee County, MS, Monroe County, MS, Panola County, MS, Pontotoc County, MS, Quitman County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Union County, MS, Yalobusha County, MS

The radar

The Memphis radar (KNQA), 113 km from the middle of the area, began a volume at 00:06 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 (KBYH), launched 00:00Z, 0.1 hours before the alert went out and 61 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: 2449 J/kg
Mixed-layer CIN: -28 J/kg
Mixed-layer LCL: 619 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 480 m²/s²
0-3 km storm-relative helicity: 618 m²/s²
Significant tornado parameter: 8.8
Supercell composite: 40.3

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 28, 1:43 AM CDT	Tornado Watch	SPC	Alcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more	8 hr
Apr 28, 2:50 AM CDT	Mesoscale Discussion	SPC	Bolivar, Coahoma, Quitman, Tunica, Washington	115 min
Apr 28, 4:40 AM CDT	Tornado Watch	SPC	Bolivar, Carroll, Grenada, Holmes, Humphreys, Issaquena and 8 more	7 hr
Apr 28, 6:57 AM CDT	Mesoscale Discussion	SPC	Alcorn, Benton, Lafayette, Lee, Marshall, Pontotoc and 4 more	2 hr
Apr 28, 7:16 AM CDT	Mesoscale Discussion	SPC	Attala, Calhoun, Carroll, Choctaw, Claiborne, Grenada and 14 more	89 min
Apr 28, 9:53 AM CDT	Mesoscale Discussion	SPC	Adams, Amite, Attala, Calhoun, Carroll, Chickasaw and 40 more	97 min
Apr 28, 12:05 PM CDT	Mesoscale Discussion	SPC	Adams, Alcorn, Attala, Benton, Calhoun, Carroll and 40 more	115 min
Apr 28, 12:39 PM CDT	Tornado Watch PDS	SPC	Adams, Alcorn, Attala, Benton, Calhoun, Carroll and 48 more	8 hr
Apr 28, 2:09 PM CDT	Mesoscale Discussion	SPC	Alcorn, Attala, Calhoun, Carroll, Chickasaw, Choctaw and 32 more	66 min
Apr 28, 3:49 PM CDT	Mesoscale Discussion	SPC	Choctaw, Clay, Itawamba, Leake, Lowndes, Monroe and 4 more	86 min
Apr 28, 5:22 PM CDT	Mesoscale Discussion	SPC	Attala, Chickasaw, Choctaw, Clay, Hinds, Holmes and 18 more	83 min

Nearby

Mesoscale Discussions in Mississippi, 2014 Every mesoscale discussion in 2014

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.