Alert archive / Alabama / Mesoscale Discussions in 2019

Mesoscale Discussion 2242

December 29, 20194 counties in Alabama; Noxubee County, Mississippi

The Storm Prediction Center issued this mesoscale discussion at Dec 29, 2019, 6:27 PM CST for 4 counties in Alabama; Noxubee County, Mississippi. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Dec 29, 2019, 6:27 PM CST (00:27 UTC)
Expired
Dec 29, 2019, 8:00 PM CST
In force
93 min
Issued by
the Storm Prediction Center

Counties Fayette County, AL, Pickens County, AL, Tuscaloosa County, AL, Walker County, AL, Noxubee County, MS

The radar

The Columbus AFB radar (KGWX), 73 km from the middle of the area, began a volume at 00:29 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, 0.5 hours before the alert went out and 96 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-pSkew-T log-p diagram, Birmingham, AL at 00:00Z on 2019-12-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 320 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Birmingham, AL at 00:00Z on 2019-12-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 417 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
320 J/kg
Mixed-layer CIN
-26 J/kg
Mixed-layer LCL
767 m above ground
0-6 km bulk shear
67 kt
0-1 km storm-relative helicity
417 m²/s²
0-3 km storm-relative helicity
502 m²/s²
Significant tornado parameter
1.0
Supercell composite
6.5

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.

IssuedProductOfficeCountiesLasted
Dec 29, 6:05 PM CSTMesoscale DiscussionSPCBibb, Blount, Cherokee, Choctaw, Colbert, Cullman and 25 more85 min

Nearby

Mesoscale Discussions in Alabama, 2019Mesoscale Discussions in Mississippi, 2019Every mesoscale discussion in 2019

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.