Alert archive / Tennessee / Mesoscale Discussions in 2020

Mesoscale Discussion 1608

August 28, 20204 counties in Kentucky; 5 counties in Mississippi; 12 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Aug 28, 2020, 6:47 AM CDT for 4 counties in Kentucky; 5 counties in Mississippi; 12 counties in Tennessee. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued: Aug 28, 2020, 6:47 AM CDT (11:47 UTC)
Expired: Aug 28, 2020, 8:15 AM CDT
In force: 88 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...watch unlikely
Chance of a watch: 20%

All 21 counties

Carlisle County, KY, Fulton County, KY, Graves County, KY, Hickman County, KY, Benton County, MS, Lafayette County, MS, Marshall County, MS, Tippah County, MS, Union County, MS, Carroll County, TN, Chester County, TN, Crockett County, TN, Dyer County, TN, Fayette County, TN, Gibson County, TN, Hardeman County, TN, Haywood County, TN, Madison County, TN, McNairy County, TN, Obion County, TN, Weakley County, TN

The radar

The Memphis radar (KNQA), 66 km from the middle of the area, began a volume at 11:49 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 463Aug 28, 10:30 AM CDT

The nearest sounding before it

Little Rock, AR (KLZK), launched 00:00Z, 11.8 hours before the alert went out and 96 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: 582 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -48 m²/s²
0-3 km storm-relative helicity: 78 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
Aug 28, 1:04 PM CDT	Tornado Watch	SPC	Adair, Allen, Barren, Breckinridge, Butler, Clinton and 21 more	3 hr
Aug 28, 1:25 PM CDT	Mesoscale Discussion	SPC	Allen, Barren, Butler, Edmonson, Grayson, Hancock and 3 more	65 min
Aug 27, 8:29 PM CDT	Mesoscale Discussion	SPC	Marshall	2 hr
Aug 28, 10:09 AM CDT	Mesoscale Discussion	SPC	Alcorn, Lee, Prentiss, Tishomingo, Union	96 min
Aug 28, 10:31 AM CDT	Tornado Watch	SPC	Alcorn, Calhoun, Chickasaw, Itawamba, Lee, Monroe and 5 more	5 hr
Aug 28, 3:46 PM CDT	Tornado Watch	SPC	Itawamba, Monroe	4 hr
Aug 28, 5:19 PM CDT	Mesoscale Discussion	SPC	Franklin, Grundy, Hamilton, Lincoln, Marion, Moore	116 min
Aug 28, 6:50 PM CDT	Mesoscale Discussion	SPC	Johnson	2 hr

Nearby

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