Alert archive / Alabama / Mesoscale Discussions in 2020

Mesoscale Discussion 229

March 24, 20204 counties in Alabama; 4 counties in Tennessee

The Storm Prediction Center issued this mesoscale discussion at Mar 24, 2020, 5:35 PM CDT for 4 counties in Alabama; 4 counties in Tennessee. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Mar 24, 2020, 5:35 PM CDT (22:35 UTC)
Expired: Mar 24, 2020, 7:00 PM CDT
In force: 85 min
Issued by: the Storm Prediction Center

Counties Colbert County, AL, Lauderdale County, AL, Limestone County, AL, Madison County, AL, Giles County, TN, Lawrence County, TN, Lincoln County, TN, Moore County, TN

The radar

The Northeast Alabama radar (KHTX), 95 km from the middle of the area, began a volume at 22:38 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 12:00Z, 10.6 hours before the alert went out and 143 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: 862 m above ground
0-6 km bulk shear: 60 kt
0-1 km storm-relative helicity: 14 m²/s²
0-3 km storm-relative helicity: 86 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
Mar 24, 2:34 PM CDT	Mesoscale Discussion	SPC	Colbert, Franklin, Lauderdale, Lawrence, Limestone, Marion	116 min
Mar 24, 3:06 PM CDT	Tornado Watch	SPC	Colbert, Cullman, DeKalb, Franklin, Jackson, Lamar and 8 more	7 hr
Mar 24, 11:27 AM CDT	Mesoscale Discussion	SPC	Benton, Carroll, Cheatham, Chester, Crockett, Davidson and 29 more	2 hr

Nearby

Mesoscale Discussions in Alabama, 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.