Alert archive / Mississippi / Mesoscale Discussions in 2015

Mesoscale Discussion 15

January 3, 2015Choctaw County, Alabama; 5 parishes in Louisiana; 15 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Jan 3, 2015, 5:31 PM CST for Choctaw County, Alabama; 5 parishes in Louisiana; 15 counties in Mississippi. It was in force for 44 min.

The area

The outline as issued.

The facts

Issued: Jan 3, 2015, 5:31 PM CST (23:31 UTC)
Expired: Jan 3, 2015, 6:15 PM CST
In force: 44 min
Issued by: the Storm Prediction Center

All 21 counties

Choctaw County, AL, Livingston Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, Clarke County, MS, Covington County, MS, Forrest County, MS, Greene County, MS, Hancock County, MS, Jasper County, MS, Jones County, MS, Lamar County, MS, Lauderdale County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 122 km from the middle of the area, began a volume at 23:35 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

Jackson, MS (KJAN), launched 12:00Z, 11.5 hours before the alert went out and 130 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: 92 J/kg
Mixed-layer CIN: -86 J/kg
Mixed-layer LCL: 505 m above ground
0-6 km bulk shear: 49 kt
0-1 km storm-relative helicity: 353 m²/s²
0-3 km storm-relative helicity: 556 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 2.3

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
Jan 3, 12:00 PM CST	Mesoscale Discussion	SPC	Baldwin, Mobile	90 min
Jan 3, 1:43 PM CST	Mesoscale Discussion	SPC	Choctaw, Sumter, Washington	92 min
Jan 3, 2:54 PM CST	Mesoscale Discussion	SPC	Bibb, Choctaw, Clarke, Dallas, Fayette, Greene and 11 more	96 min
Jan 3, 3:18 PM CST	Tornado Watch	SPC	Autauga, Bibb, Blount, Chilton, Dallas, Fayette and 15 more	5 hr
Jan 3, 4:47 PM CST	Mesoscale Discussion	SPC	Autauga, Butler, Chilton, Conecuh, Coosa, Crenshaw and 6 more	58 min
Jan 3, 5:59 PM CST	Mesoscale Discussion	SPC	Bibb, Colbert, Cullman, Fayette, Franklin, Greene and 11 more	61 min
Jan 3, 10:24 AM CST	Mesoscale Discussion	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberville, Lafourche and 14 more	2 hr
Jan 3, 11:04 AM CST	Tornado Watch	SPC	Ascension, Assumption, East Baton Rouge, East Feliciana, Iberia, Iberville and 22 more	7 hr

Nearby

Mesoscale Discussions in Mississippi, 2015 Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Alabama, 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.