Alert archive / Mississippi / Mesoscale Discussions in 2023

Mesoscale Discussion 72

January 18, 20234 states

The Storm Prediction Center issued this mesoscale discussion at Jan 18, 2023, 12:30 PM CST for 4 states. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Jan 18, 2023, 12:30 PM CST (18:30 UTC)
Expired: Jan 18, 2023, 2:00 PM CST
In force: 90 min
Issued by: the Storm Prediction Center
Concerning: Severe potential...tornado watch likely
Chance of a watch: 80%

All 44 counties

Ashley County, AR, Chicot County, AR, Crittenden County, AR, Cross County, AR, Lee County, AR, Phillips County, AR, St. Francis County, AR, Caldwell Parish, LA, Catahoula Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Grant Parish, LA, LaSalle Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Ouachita Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Winn Parish, LA, Bolivar County, MS, Carroll County, MS, Coahoma County, MS, DeSoto County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Lafayette County, MS, Leflore County, MS, Marshall County, MS, Panola County, MS, Quitman County, MS, Sharkey County, MS, Sunflower County, MS, Tallahatchie County, MS, Tate County, MS, Tunica County, MS, Warren County, MS, Washington County, MS, Yalobusha County, MS, Yazoo County, MS, Fayette County, TN, Shelby County, TN

The radar

The Jackson/Brandon,MS radar (KDGX), 166 km from the middle of the area, began a volume at 18:32 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 25Jan 18, 2:35 PM CST

The nearest sounding before it

Little Rock, AR (KLZK), launched 12:00Z, 6.5 hours before the alert went out and 194 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: 597 J/kg
Mixed-layer CIN: -22 J/kg
Mixed-layer LCL: 487 m above ground
0-6 km bulk shear: 76 kt
0-1 km storm-relative helicity: 249 m²/s²
0-3 km storm-relative helicity: 244 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.7

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
Jan 18, 7:28 AM CST	Mesoscale Discussion	SPC	Clark, Columbia, Hempstead, Howard, Lafayette, Little River and 5 more	2 hr
Jan 18, 9:02 AM CST	Tornado Watch	SPC	Arkansas, Bradley, Calhoun, Clark, Cleveland, Columbia and 25 more	9 hr
Jan 18, 11:48 AM CST	Mesoscale Discussion	SPC	Bradley, Calhoun, Cleveland, Columbia, Dallas, Grant and 3 more	87 min
Jan 18, 2:34 PM CST	Tornado Watch	SPC	Ashley, Chicot, Crittenden, Lee, Phillips, St. Francis	7 hr
Jan 18, 3:31 PM CST	Mesoscale Discussion	SPC	Ashley, Chicot, Desha	89 min
Jan 18, 5:47 PM CST	Mesoscale Discussion	SPC	Catahoula, Concordia, East Carroll, Franklin, Madison, Tensas	118 min

Nearby

Mesoscale Discussions in Mississippi, 2023 Mesoscale Discussions in Louisiana, 2023 Mesoscale Discussions in Arkansas, 2023 Every mesoscale discussion in 2023

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.