Alert archive / Alabama / Mesoscale Discussions in 2020

Mesoscale Discussion 85

February 5, 202015 counties in Alabama; Washington Parish, Louisiana; 14 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Feb 5, 2020, 11:15 PM CST for 15 counties in Alabama; Washington Parish, Louisiana; 14 counties in Mississippi. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Feb 5, 2020, 11:15 PM CST (05:15 UTC)
Expired: Feb 6, 2020, 1:15 AM CST
In force: 2 hr
Issued by: the Storm Prediction Center

All 30 counties

Bibb County, AL, Chilton County, AL, Choctaw County, AL, Clarke County, AL, Dallas County, AL, Greene County, AL, Hale County, AL, Jefferson County, AL, Marengo County, AL, Perry County, AL, Shelby County, AL, Sumter County, AL, Tuscaloosa County, AL, Washington County, AL, Wilcox County, AL, Washington Parish, LA, Clarke County, MS, Covington County, MS, Forrest County, MS, Greene County, MS, Jasper County, MS, Jefferson Davis County, MS, Jones County, MS, Kemper County, MS, Lamar County, MS, Lauderdale County, MS, Marion County, MS, Perry County, MS, Walthall County, MS, Wayne County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 136 km from the middle of the area, began a volume at 05:15 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 25Feb 5, 11:50 PM CST

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 5.3 hours before the alert went out and 146 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: 847 J/kg
Mixed-layer CIN: -69 J/kg
Mixed-layer LCL: 592 m above ground
0-6 km bulk shear: 66 kt
0-1 km storm-relative helicity: 298 m²/s²
0-3 km storm-relative helicity: 390 m²/s²
Significant tornado parameter: 1.9
Supercell composite: 10.5

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.

Issued	Product	Office	Counties	Lasted
Feb 5, 6:33 PM CST	Mesoscale Discussion	SPC	Jackson, Limestone, Madison	117 min
Feb 5, 9:43 PM CST	Mesoscale Discussion	SPC	Choctaw, Greene, Hale, Marengo, Perry, Pickens and 2 more	2 hr
Feb 5, 11:48 PM CST	Tornado Watch	SPC	Autauga, Baldwin, Bibb, Calhoun, Cherokee, Chilton and 18 more	8 hr
Feb 6, 2:02 AM CST	Mesoscale Discussion	SPC	Baldwin, Barbour, Bullock, Butler, Chambers, Coffee and 18 more	88 min
Feb 6, 3:27 AM CST	Tornado Watch	SPC	Autauga, Baldwin, Barbour, Bullock, Butler, Chambers and 20 more	9 hr
Feb 6, 4:33 AM CST	Mesoscale Discussion	SPC	Chilton, Clarke, Dallas, Monroe, Perry, Washington and 1 more	87 min
Feb 6, 6:40 AM CST	Mesoscale Discussion	SPC	Chambers, Clay, Cleburne, Coosa, Elmore, Randolph and 2 more	95 min
Feb 6, 10:00 AM CST	Mesoscale Discussion	SPC	Barbour, Bullock, Chambers, Coffee, Covington, Crenshaw and 9 more	2 hr
Feb 6, 11:17 AM CST	Tornado Watch	SPC	Coffee, Dale, Geneva, Henry, Houston	8 hr

Nearby

Mesoscale Discussions in Alabama, 2020 Mesoscale Discussions in Mississippi, 2020 Mesoscale Discussions in Louisiana, 2020 Every 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.