Alert archive / Alabama / Mesoscale Discussions in 2015

Mesoscale Discussion 2105

December 28, 2015Barbour County, Russell County, Alabama; Muscogee County, Georgia

The Storm Prediction Center issued this mesoscale discussion at Dec 28, 2015, 3:31 PM CST for Barbour County, Russell County, Alabama; Muscogee County, Georgia. It was in force for 29 min.

The area

The outline as issued.

The facts

Issued: Dec 28, 2015, 3:31 PM CST (21:31 UTC)
Expired: Dec 28, 2015, 4:00 PM CST
In force: 29 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

Counties Barbour County, AL, Russell County, AL, Muscogee County, GA

The radar

The Maxwell AFB radar (KMXX), 65 km from the middle of the area, began a volume at 21:30 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 nearest sounding before it

Birmingham, AL (KBMX), launched 12:00Z, 9.5 hours before the alert went out and 182 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: 144 J/kg
Mixed-layer CIN: -13 J/kg
Mixed-layer LCL: 584 m above ground
0-6 km bulk shear: 41 kt
0-1 km storm-relative helicity: 330 m²/s²
0-3 km storm-relative helicity: 377 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.3

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
Dec 28, 6:41 AM CST	Tornado Watch	SPC	Autauga, Baldwin, Bibb, Butler, Chilton, Choctaw and 27 more	5 hr
Dec 28, 8:38 AM CST	Mesoscale Discussion	SPC	Colbert, Franklin, Lauderdale, Lawrence, Limestone, Madison and 1 more	67 min
Dec 28, 10:21 AM CST	Mesoscale Discussion	SPC	Autauga, Barbour, Bibb, Blount, Bullock, Butler and 34 more	84 min
Dec 28, 11:04 AM CST	Tornado Watch	SPC	Butler, Coffee, Conecuh, Covington, Crenshaw, Dale and 4 more	7 hr
Dec 28, 2:27 PM CST	Mesoscale Discussion	SPC	Barbour, Bullock, Coffee, Dale, Geneva, Pike	33 min
Dec 28, 5:07 PM CST	Mesoscale Discussion	SPC	Houston	53 min

Nearby

Mesoscale Discussions in Alabama, 2015 Mesoscale Discussions in Georgia, 2015 Every mesoscale discussion in 2015

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.