Alert archive / Alabama / Mesoscale Discussions in 2020

Mesoscale Discussion 268

March 29, 202010 counties in Alabama; Lowndes County, Noxubee County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Mar 29, 2020, 2:17 AM CDT for 10 counties in Alabama; Lowndes County, Noxubee County, Mississippi. It was in force for 88 min.

The area

The outline as issued.

The facts

Issued: Mar 29, 2020, 2:17 AM CDT (07:17 UTC)
Expired: Mar 29, 2020, 3:45 AM CDT
In force: 88 min
Issued by: the Storm Prediction Center

Counties Blount County, AL, Cullman County, AL, Fayette County, AL, Jefferson County, AL, Lamar County, AL, Marion County, AL, Pickens County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Lowndes County, MS, Noxubee County, MS

The radar

The Columbus AFB radar (KGWX), 49 km from the middle of the area, began a volume at 07:21 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

Birmingham, AL (KBMX), launched 00:00Z, 7.3 hours before the alert went out and 116 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: 108 J/kg
Mixed-layer CIN: -329 J/kg
Mixed-layer LCL: 1672 m above ground
0-6 km bulk shear: 55 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 157 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

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 28, 8:25 PM CDT	Mesoscale Discussion	SPC	Colbert, Franklin, Lauderdale, Lawrence, Marion	95 min
Mar 28, 9:58 PM CDT	Tornado Watch	SPC	Blount, Colbert, Cullman, DeKalb, Fayette, Franklin and 16 more	7 hr
Mar 28, 11:27 PM CDT	Mesoscale Discussion	SPC	Colbert, Franklin, Lamar, Lauderdale, Lawrence, Limestone and 2 more	93 min
Mar 29, 1:50 AM CDT	Mesoscale Discussion	SPC	Jackson, Lawrence, Limestone, Madison	85 min
Mar 28, 7:46 PM CDT	Mesoscale Discussion	SPC	Attala, Claiborne, Hinds, Holmes, Humphreys, Issaquena and 7 more	89 min

Nearby

Mesoscale Discussions in Alabama, 2020 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.