Alert archive / Mississippi / Mesoscale Discussions in 2020

Mesoscale Discussion 455

April 23, 20204 states

The Storm Prediction Center issued this mesoscale discussion at Apr 23, 2020, 2:28 AM CDT for 4 states. It was in force for 92 min.

The area

The outline as issued.

The facts

Issued: Apr 23, 2020, 2:28 AM CDT (07:28 UTC)
Expired: Apr 23, 2020, 4:00 AM CDT
In force: 92 min
Issued by: the Storm Prediction Center

All 63 counties

Baldwin County, AL, Choctaw County, AL, Clarke County, AL, Conecuh County, AL, Escambia County, AL, Mobile County, AL, Monroe County, AL, Washington County, AL, Escambia County, FL, Santa Rosa County, FL, Acadia Parish, LA, Ascension Parish, LA, Avoyelles Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Evangeline Parish, LA, Iberville Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Livingston Parish, LA, Orleans Parish, LA, Pointe Coupee Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Claiborne County, MS, Clarke County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, George County, MS, Greene County, MS, Hancock County, MS, Harrison County, MS, Jackson County, MS, Jasper County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Simpson County, MS, Smith County, MS, Stone County, MS, Walthall County, MS, Wayne County, MS, Wilkinson County, MS

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 139Apr 23, 4:05 AM CDT

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 7.5 hours before the alert went out and 97 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: 8 J/kg
Mixed-layer CIN: -206 J/kg
Mixed-layer LCL: 885 m above ground
0-6 km bulk shear: 66 kt
0-1 km storm-relative helicity: 337 m²/s²
0-3 km storm-relative helicity: 666 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Apr 23, 4:05 AM CDT	Tornado Watch	SPC	Baldwin, Barbour, Bullock, Butler, Choctaw, Clarke and 14 more	11 hr
Apr 23, 7:43 AM CDT	Mesoscale Discussion	SPC	Baldwin, Barbour, Butler, Coffee, Conecuh, Covington and 9 more	92 min
Apr 23, 9:29 AM CDT	Mesoscale Discussion	SPC	Houston	61 min
Apr 23, 1:37 PM CDT	Mesoscale Discussion	SPC	Choctaw, Clarke, Greene, Hale, Marengo, Perry and 3 more	113 min
Apr 23, 4:06 PM CDT	Severe Thunderstorm Watch	SPC	Autauga, Bibb, Chambers, Chilton, Choctaw, Clarke and 17 more	113 min
Apr 23, 9:52 AM CDT	Tornado Watch	SPC	Franklin, Gadsden, Gulf, Hamilton, Jefferson, Leon and 4 more	6 hr
Apr 23, 12:05 PM CDT	Mesoscale Discussion	SPC	Bay, Escambia, Okaloosa, Santa Rosa, Walton, Washington	55 min
Apr 23, 2:28 PM CDT	Mesoscale Discussion	SPC	Bay, Calhoun, Franklin, Gulf, Jefferson, Leon and 6 more	62 min
Apr 23, 2:47 PM CDT	Tornado Watch	SPC	Bay, Calhoun, Dixie, Franklin, Gadsden, Gulf and 11 more	6 hr
Apr 23, 5:09 PM CDT	Mesoscale Discussion	SPC	Alachua, Baker, Bradford, Calhoun, Clay, Columbia and 17 more	96 min
Apr 23, 5:52 PM CDT	Tornado Watch	SPC	Alachua, Baker, Bradford, Clay, Columbia, Duval and 7 more	5 hr
Apr 22, 7:01 PM CDT	Mesoscale Discussion	SPC	Beauregard, Vernon	89 min
Apr 22, 7:41 PM CDT	Mesoscale Discussion	SPC	Vernon	34 min
Apr 22, 8:26 PM CDT	Mesoscale Discussion	SPC	De Soto, Natchitoches, Sabine	94 min
Apr 22, 9:31 PM CDT	Mesoscale Discussion	SPC	Avoyelles, Concordia, East Feliciana, Pointe Coupee, Saint Helena, Washington and 1 more	89 min
Apr 22, 9:47 PM CDT	Tornado Watch	SPC	Ascension, Catahoula, Concordia, East Baton Rouge, East Feliciana, Franklin and 12 more	9 hr
Apr 22, 10:17 PM CDT	Mesoscale Discussion	SPC	Caldwell, Grant, LaSalle, Natchitoches, Sabine, Winn	88 min
Apr 22, 11:16 PM CDT	Mesoscale Discussion	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Caldwell and 15 more	89 min
Apr 23, 12:02 AM CDT	Tornado Watch	SPC	Acadia, Allen, Avoyelles, Beauregard, Calcasieu, Evangeline and 5 more	4 hr

Nearby

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