Alert archive / Tennessee / Mesoscale Discussions in 2011

Mesoscale Discussion 2346

November 21, 20114 states

The Storm Prediction Center issued this mesoscale discussion at Nov 21, 2011, 3:40 AM CST for 4 states. It was in force for 95 min.

The area

The outline as issued.

The facts

Issued: Nov 21, 2011, 3:40 AM CST (09:40 UTC)
Expired: Nov 21, 2011, 5:15 AM CST
In force: 95 min
Issued by: the Storm Prediction Center

All 38 counties

Lauderdale County, AL, Crittenden County, AR, Cross County, AR, Lee County, AR, St. Francis County, AR, Alcorn County, MS, Benton County, MS, DeSoto County, MS, Marshall County, MS, Tunica County, MS, Benton County, TN, Carroll County, TN, Chester County, TN, Crockett County, TN, Davidson County, TN, Decatur County, TN, Dickson County, TN, Fayette County, TN, Gibson County, TN, Giles County, TN, Hardeman County, TN, Hardin County, TN, Haywood County, TN, Henderson County, TN, Hickman County, TN, Humphreys County, TN, Lauderdale County, TN, Lawrence County, TN, Lewis County, TN, Madison County, TN, Marshall County, TN, Maury County, TN, McNairy County, TN, Perry County, TN, Shelby County, TN, Tipton County, TN, Wayne County, TN, Williamson County, TN

The radar

The Memphis radar (KNQA), 102 km from the middle of the area, began a volume at 09:40 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

Nashville Metro, TN (KBNA), launched 00:00Z, 9.7 hours before the alert went out and 214 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 0 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 213 m²/s²
0-3 km storm-relative helicity: 259 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

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
Nov 20, 8:02 PM CST	Mesoscale Discussion	SPC	Howard, Little River, Logan, Montgomery, Pike, Polk and 4 more	58 min

Nearby

Mesoscale Discussions in Tennessee, 2011 Mesoscale Discussions in Mississippi, 2011 Mesoscale Discussions in Arkansas, 2011 Every mesoscale discussion in 2011

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.