Alert archive / Alabama / Mesoscale Discussions in 2014

Mesoscale Discussion 479

April 29, 20144 states

The Storm Prediction Center issued this mesoscale discussion at Apr 29, 2014, 3:27 PM CDT for 4 states. It was in force for 33 min.

The area

The outline as issued.

The facts

Issued: Apr 29, 2014, 3:27 PM CDT (20:27 UTC)
Expired: Apr 29, 2014, 4:00 PM CDT
In force: 33 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 34 counties

Bibb County, AL, Blount County, AL, Choctaw County, AL, Colbert County, AL, Cullman County, AL, DeKalb County, AL, Fayette County, AL, Franklin County, AL, Greene County, AL, Hale County, AL, Jackson County, AL, Jefferson County, AL, Lamar County, AL, Lauderdale County, AL, Lawrence County, AL, Limestone County, AL, Madison County, AL, Marengo County, AL, Marion County, AL, Marshall County, AL, Morgan County, AL, Pickens County, AL, Sumter County, AL, Tuscaloosa County, AL, Walker County, AL, Winston County, AL, Dade County, GA, Itawamba County, MS, Monroe County, MS, Franklin County, TN, Giles County, TN, Lincoln County, TN, Marion County, TN, Moore County, TN

The radar

The Columbus AFB radar (KGWX), 86 km from the middle of the area, began a volume at 20:30 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 118Apr 29, 3:55 PM CDT

The nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 8.5 hours before the alert went out and 85 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: 22 J/kg
Mixed-layer CIN: -219 J/kg
Mixed-layer LCL: 1562 m above ground
0-6 km bulk shear: 80 kt
0-1 km storm-relative helicity: 3 m²/s²
0-3 km storm-relative helicity: 36 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
Apr 28, 7:12 PM CDT	Mesoscale Discussion	SPC	Colbert, Cullman, Fayette, Franklin, Jackson, Lamar and 10 more	93 min
Apr 28, 7:59 PM CDT	Tornado Watch	SPC	Autauga, Baldwin, Barbour, Bibb, Blount, Bullock and 51 more	11 hr
Apr 28, 9:34 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Calhoun, Cherokee, Chilton and 23 more	86 min
Apr 28, 10:53 PM CDT	Mesoscale Discussion	SPC	Bibb, Blount, Etowah, Jefferson, Marshall, St. Clair and 2 more	97 min
Apr 28, 11:20 PM CDT	Mesoscale Discussion	SPC	Autauga, Bibb, Blount, Calhoun, Cherokee, Chilton and 21 more	85 min
Apr 29, 1:38 AM CDT	Mesoscale Discussion	SPC	Baldwin, Barbour, Bullock, Butler, Chambers, Coffee and 18 more	67 min
Apr 29, 1:56 AM CDT	Tornado Watch	SPC	Coffee, Dale, Geneva, Henry, Houston	9 hr
Apr 29, 4:01 AM CDT	Mesoscale Discussion	SPC	Barbour, Chambers, Dale, Geneva, Henry, Houston and 3 more	89 min
Apr 29, 12:46 PM CDT	Tornado Watch	SPC	Baldwin, Mobile, Washington	10 hr
Apr 29, 3:56 PM CDT	Tornado Watch	SPC	Bibb, Blount, Calhoun, Cherokee, Chilton, Colbert and 27 more	4 hr
Apr 29, 3:58 PM CDT	Mesoscale Discussion	SPC	Clarke, Conecuh, Covington, Escambia, Monroe	92 min
Apr 29, 6:01 PM CDT	Mesoscale Discussion	SPC	Choctaw, Washington	89 min
Apr 29, 6:55 PM CDT	Mesoscale Discussion	SPC	Bibb, Blount, Calhoun, Cullman, DeKalb, Etowah and 17 more	95 min
Apr 28, 10:29 PM CDT	Mesoscale Discussion	SPC	Banks, Habersham, Hall, Rabun, Stephens, Towns and 1 more	61 min
Apr 28, 11:30 PM CDT	Tornado Watch	SPC	Banks, Dawson, Forsyth, Franklin, Habersham, Hall and 7 more	7 hr
Apr 29, 7:13 AM CDT	Mesoscale Discussion	SPC	Ben Hill, Bleckley, Brooks, Colquitt, Cook, Crisp and 13 more	92 min
Apr 29, 10:13 AM CDT	Mesoscale Discussion	SPC	Atkinson, Berrien, Brooks, Clinch, Colquitt, Cook and 5 more	62 min
Apr 29, 12:02 PM CDT	Mesoscale Discussion	SPC	Adams, Amite, Attala, Carroll, Choctaw, Claiborne and 41 more	88 min
Apr 28, 9:10 PM CDT	Mesoscale Discussion	SPC	Anderson, Campbell, Claiborne, Grainger, Morgan, Scott and 1 more	65 min
Apr 29, 2:10 PM CDT	Mesoscale Discussion	SPC	Cannon, Cheatham, Clay, Davidson, DeKalb, Jackson and 8 more	65 min

Nearby

Mesoscale Discussions in Alabama, 2014 Mesoscale Discussions in Tennessee, 2014 Mesoscale Discussions in Mississippi, 2014 Every mesoscale discussion in 2014

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.