Alert archive / Alabama / Mesoscale Discussions in 2016

Mesoscale Discussion 1846

November 29, 201612 counties in Alabama; 12 counties in Mississippi; Hardin County, Lawrence County, Wayne County, Tennessee

The Storm Prediction Center issued this mesoscale discussion at Nov 29, 2016, 6:43 PM CST for 12 counties in Alabama; 12 counties in Mississippi; Hardin County, Lawrence County, Wayne County, Tennessee. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Nov 29, 2016, 6:43 PM CST (00:43 UTC)
Expired: Nov 29, 2016, 8:15 PM CST
In force: 92 min
Issued by: the Storm Prediction Center

All 27 counties

Colbert County, AL, Fayette County, AL, Franklin County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Marion County, AL, Pickens County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Alcorn County, MS, Chickasaw County, MS, Clay County, MS, Itawamba County, MS, Lee County, MS, Lowndes County, MS, Monroe County, MS, Oktibbeha County, MS, Pontotoc County, MS, Prentiss County, MS, Tishomingo County, MS, Webster County, MS, Hardin County, TN, Lawrence County, TN, Wayne County, TN

The radar

The Columbus AFB radar (KGWX), 60 km from the middle of the area, began a volume at 00:46 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.

The nearest sounding before it

Birmingham, AL (KBMX), launched 00:00Z, 0.7 hours before the alert went out and 166 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: 606 J/kg
Mixed-layer CIN: -32 J/kg
Mixed-layer LCL: 698 m above ground
0-6 km bulk shear: 67 kt
0-1 km storm-relative helicity: 410 m²/s²
0-3 km storm-relative helicity: 477 m²/s²
Significant tornado parameter: 1.7
Supercell composite: 7.4

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
Nov 29, 6:47 PM CST	Tornado Watch	SPC	Cullman, DeKalb, Jackson, Lawrence, Limestone, Madison and 2 more	8 hr
Nov 29, 8:03 PM CST	Mesoscale Discussion	SPC	Choctaw, Fayette, Greene, Hale, Lamar, Pickens and 2 more	2 hr
Nov 29, 8:50 PM CST	Tornado Watch	SPC	Bibb, Blount, Fayette, Greene, Hale, Jefferson and 7 more	8 hr
Nov 29, 9:28 PM CST	Mesoscale Discussion	SPC	Cullman, DeKalb, Jackson, Lawrence, Limestone, Madison and 2 more	62 min
Nov 29, 10:28 PM CST	Tornado Watch	SPC	Colbert, Cullman, DeKalb, Franklin, Jackson, Lauderdale and 5 more	5 hr
Nov 29, 11:17 PM CST	Mesoscale Discussion	SPC	DeKalb, Jackson, Lawrence, Limestone, Madison, Morgan	118 min
Nov 29, 11:37 PM CST	Mesoscale Discussion	SPC	Fayette, Lamar, Pickens	113 min
Nov 30, 1:07 AM CST	Mesoscale Discussion	SPC	Blount, Cullman, DeKalb, Fayette, Jackson, Madison and 5 more	53 min
Nov 30, 2:54 AM CST	Tornado Watch	SPC	Bibb, Blount, Calhoun, Cherokee, Chilton, Cleburne and 22 more	7 hr
Nov 30, 4:57 AM CST	Tornado Watch	SPC	Choctaw, Clarke, Mobile, Washington	7 hr
Nov 30, 5:10 AM CST	Mesoscale Discussion	SPC	Bibb, Blount, Calhoun, Cherokee, Chilton, Clay and 27 more	95 min
Nov 30, 9:00 AM CST	Mesoscale Discussion	SPC	Autauga, Baldwin, Bibb, Blount, Bullock, Butler and 37 more	2 hr
Nov 30, 11:06 AM CST	Tornado Watch	SPC	Baldwin, Barbour, Bullock, Butler, Chambers, Coffee and 17 more	6 hr
Nov 30, 12:59 PM CST	Mesoscale Discussion	SPC	Barbour, Bullock, Coffee, Covington, Crenshaw, Dale and 7 more	2 hr
Nov 30, 1:55 PM CST	Mesoscale Discussion	SPC	Barbour, Coffee, Covington, Dale, Geneva, Henry and 2 more	2 hr
Nov 29, 6:06 PM CST	Mesoscale Discussion	SPC	Attala, Choctaw, Claiborne, Hinds, Holmes, Humphreys and 13 more	114 min
Nov 29, 9:47 PM CST	Mesoscale Discussion	SPC	Adams, Amite, Claiborne, Copiah, Franklin, Hinds and 5 more	58 min
Nov 30, 3:33 AM CST	Mesoscale Discussion	SPC	Amite, Clarke, Covington, Forrest, Hancock, Jasper and 17 more	87 min
Nov 29, 10:11 PM CST	Tornado Watch	SPC	Bledsoe, Bradley, Hamilton, McMinn, Marion, Meigs and 2 more	5 hr
Nov 29, 11:46 PM CST	Mesoscale Discussion	SPC	Anderson, Blount, Campbell, Claiborne, Grainger, Hamblen and 6 more	119 min

Nearby

Mesoscale Discussions in Alabama, 2016 Mesoscale Discussions in Mississippi, 2016 Mesoscale Discussions in Tennessee, 2016 Every mesoscale discussion in 2016

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.