Alert archive / Alabama / Mesoscale Discussions in 2014

Mesoscale Discussion 468

April 28, 20148 counties in Alabama

The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2014, 10:53 PM CDT for 8 counties in Alabama. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued: Apr 28, 2014, 10:53 PM CDT (03:53 UTC)
Expired: Apr 29, 2014, 12:30 AM CDT
In force: 97 min
Issued by: the Storm Prediction Center

Counties Bibb County, AL, Blount County, AL, Etowah County, AL, Jefferson County, AL, Marshall County, AL, Shelby County, AL, St. Clair County, AL, Tuscaloosa County, AL

The radar

The Birmingham radar (KBMX), 36 km from the middle of the area, began a volume at 03:56 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, 3.9 hours before the alert went out and 35 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: 1160 J/kg
Mixed-layer CIN: -40 J/kg
Mixed-layer LCL: 1240 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 236 m²/s²
0-3 km storm-relative helicity: 361 m²/s²
Significant tornado parameter: 1.6
Supercell composite: 9.6

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, 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, 3:27 PM CDT	Mesoscale Discussion	SPC	Bibb, Blount, Choctaw, Colbert, Cullman, DeKalb and 20 more	33 min
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

Nearby

Mesoscale Discussions in Alabama, 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.