Alert archive / Alabama / Mesoscale Discussions in 2020

Mesoscale Discussion 374

April 12, 20204 states

The Storm Prediction Center issued this mesoscale discussion at Apr 12, 2020, 10:28 PM CDT for 4 states. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued
Apr 12, 2020, 10:28 PM CDT (03:28 UTC)
Expired
Apr 13, 2020, 12:00 AM CDT
In force
92 min
Issued by
the Storm Prediction Center
All 80 counties

Autauga County, AL, Baldwin County, AL, Barbour County, AL, Bullock County, AL, Butler County, AL, Calhoun County, AL, Chambers County, AL, Chilton County, AL, Clarke County, AL, Clay County, AL, Cleburne County, AL, Coffee County, AL, Conecuh County, AL, Coosa County, AL, Covington County, AL, Crenshaw County, AL, Dale County, AL, Dallas County, AL, Elmore County, AL, Escambia County, AL, Geneva County, AL, Henry County, AL, Houston County, AL, Lee County, AL, Lowndes County, AL, Macon County, AL, Mobile County, AL, Monroe County, AL, Montgomery County, AL, Pike County, AL, Randolph County, AL, Russell County, AL, Shelby County, AL, St. Clair County, AL, Talladega County, AL, Tallapoosa County, AL, Washington County, AL, Wilcox County, AL, Escambia County, FL, Holmes County, FL, Okaloosa County, FL, Santa Rosa County, FL, Walton County, FL, Butts County, GA, Carroll County, GA, Chattahoochee County, GA, Clay County, GA, Clayton County, GA, Cobb County, GA, Coweta County, GA, DeKalb County, GA, Douglas County, GA, Fayette County, GA, Fulton County, GA, Gwinnett County, GA, Haralson County, GA, Harris County, GA, Heard County, GA, Henry County, GA, Jasper County, GA, Lamar County, GA, Marion County, GA, Meriwether County, GA, Monroe County, GA, Morgan County, GA, Muscogee County, GA, Newton County, GA, Paulding County, GA, Pike County, GA, Polk County, GA, Quitman County, GA, Rockdale County, GA, Spalding County, GA, Stewart County, GA, Talbot County, GA, Taylor County, GA, Troup County, GA, Upson County, GA, Walton County, GA, George County, MS

The radar

The Maxwell AFB radar (KMXX), 7 km from the middle of the area, began a volume at 03:29 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 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, 3.5 hours before the alert went out and 111 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 2020-04-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 533 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 2020-04-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 401 square meters per square second.1939587897117Sfc1 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
533 J/kg
Mixed-layer CIN
-55 J/kg
Mixed-layer LCL
847 m above ground
0-6 km bulk shear
63 kt
0-1 km storm-relative helicity
401 m²/s²
0-3 km storm-relative helicity
509 m²/s²
Significant tornado parameter
1.4
Supercell composite
8.4

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.

IssuedProductOfficeCountiesLasted
Apr 12, 7:36 PM CDTMesoscale DiscussionSPCAutauga, Bibb, Blount, Calhoun, Chilton, Choctaw and 16 more84 min
Apr 12, 8:50 PM CDTMesoscale DiscussionSPCBlount, Cullman, Etowah, Jefferson, St. Clair, Shelby and 2 more55 min
Apr 12, 10:45 PM CDTTornado WatchSPCAutauga, Baldwin, Barbour, Bullock, Butler, Calhoun and 26 more8 hr
Apr 12, 11:19 PM CDTMesoscale DiscussionSPCColbert, Franklin, Lamar, Lauderdale, Lawrence, Marion86 min
Apr 13, 2:20 AM CDTTornado WatchSPCBaker, Columbia, Duval, Franklin, Gadsden, Hamilton and 9 more8 hr
Apr 13, 5:17 AM CDTMesoscale DiscussionSPCHamilton, Jefferson, Leon, Madison88 min
Apr 13, 3:06 PM CDTMesoscale DiscussionSPCAlachua, Bradford, Clay, Levy, Marion, Putnam and 1 more84 min
Apr 12, 7:41 PM CDTMesoscale DiscussionSPCBartow, Catoosa, Cherokee, Dawson, Fannin, Floyd and 13 more64 min
Apr 12, 7:57 PM CDTTornado WatchSPCRabun6 hr
Apr 12, 10:17 PM CDTMesoscale DiscussionSPCBanks, Barrow, Bartow, Catoosa, Chattooga, Cherokee and 36 more88 min
Apr 13, 12:51 AM CDTTornado WatchSPCElbert, Franklin, Habersham, Hart, Rabun, Stephens6 hr
Apr 13, 1:39 AM CDTMesoscale DiscussionSPCBaker, Baldwin, Ben Hill, Bleckley, Burke, Calhoun and 37 more96 min
Apr 12, 7:56 PM CDTMesoscale DiscussionSPCBolivar, Carroll, Coahoma, DeSoto, Grenada, Holmes and 14 more2 hr
Apr 12, 8:19 PM CDTSevere Thunderstorm WatchSPCAlcorn, Benton, Calhoun, Chickasaw, Coahoma, DeSoto and 16 more4 hr
Apr 12, 9:44 PM CDTMesoscale DiscussionSPCAlcorn, Attala, Benton, Bolivar, Calhoun, Carroll and 37 more91 min

Nearby

Mesoscale Discussions in Alabama, 2020Mesoscale Discussions in Georgia, 2020Mesoscale Discussions in Florida, 2020Every mesoscale discussion in 2020

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.