Alert archive / Mississippi / Mesoscale Discussions in 2009

Mesoscale Discussion 161

February 27, 20094 states

The Storm Prediction Center issued this mesoscale discussion at Feb 27, 2009, 10:15 AM CST for 4 states. It was in force for 90 min.

The area

The outline as issued.

The facts

Issued: Feb 27, 2009, 10:15 AM CST (16:15 UTC)
Expired: Feb 27, 2009, 11:45 AM CST
In force: 90 min
Issued by: the Storm Prediction Center

All 50 counties

Greene County, AL, Pickens County, AL, Sumter County, AL, Ashley County, AR, Bradley County, AR, Calhoun County, AR, Chicot County, AR, Clark County, AR, Cleveland County, AR, Columbia County, AR, Dallas County, AR, Desha County, AR, Drew County, AR, Hempstead County, AR, Lafayette County, AR, Lincoln County, AR, Nevada County, AR, Ouachita County, AR, Union County, AR, East Carroll Parish, LA, Morehouse Parish, LA, West Carroll Parish, LA, Attala County, MS, Bolivar County, MS, Calhoun County, MS, Carroll County, MS, Chickasaw County, MS, Choctaw County, MS, Clay County, MS, Grenada County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Kemper County, MS, Leake County, MS, Leflore County, MS, Lowndes County, MS, Madison County, MS, Montgomery County, MS, Neshoba County, MS, Noxubee County, MS, Oktibbeha County, MS, Sharkey County, MS, Sunflower County, MS, Tallahatchie County, MS, Washington County, MS, Webster County, MS, Winston County, MS, Yalobusha County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 147 km from the middle of the area, began a volume at 16:18 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 38Feb 27, 12:40 PM CST

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 4.3 hours before the alert went out and 139 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: 822 J/kg
Mixed-layer CIN: -9 J/kg
Mixed-layer LCL: 529 m above ground
0-6 km bulk shear: 50 kt
0-1 km storm-relative helicity: 293 m²/s²
0-3 km storm-relative helicity: 400 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.0

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
Feb 27, 8:29 AM CST	Mesoscale Discussion	SPC	Bibb, Blount, Chilton, Cullman, Fayette, Greene and 12 more	31 min
Feb 27, 8:40 AM CST	Severe Thunderstorm Watch	SPC	Autauga, Bibb, Chilton, Dallas, Fayette, Greene and 11 more	6 hr
Feb 27, 12:16 PM CST	Mesoscale Discussion	SPC	Sumter	89 min
Feb 27, 12:38 PM CST	Tornado Watch	SPC	Autauga, Barbour, Bibb, Bullock, Chilton, Choctaw and 20 more	7 hr
Feb 27, 2:04 PM CST	Mesoscale Discussion	SPC	Barbour, Bullock, Crenshaw, Lee, Macon, Montgomery and 2 more	56 min
Feb 27, 3:38 PM CST	Mesoscale Discussion	SPC	Greene, Hale, Perry, Sumter	97 min
Feb 27, 5:29 PM CST	Mesoscale Discussion	SPC	Autauga, Barbour, Bibb, Bullock, Butler, Chilton and 22 more	2 hr
Feb 26, 6:12 PM CST	Severe Thunderstorm Watch	SPC	Baxter, Benton, Boone, Carroll, Clark, Cleburne and 40 more	8 hr
Feb 26, 7:42 PM CST	Mesoscale Discussion	SPC	Baxter, Boone, Carroll, Clark, Clay, Cleburne and 41 more	93 min
Feb 26, 8:29 PM CST	Mesoscale Discussion	SPC	Hempstead, Lafayette, Little River, Miller, Nevada	2 hr
Feb 26, 9:09 PM CST	Mesoscale Discussion	SPC	Arkansas, Clay, Craighead, Crittenden, Cross, Grant and 12 more	96 min
Feb 26, 9:40 PM CST	Severe Thunderstorm Watch	SPC	Arkansas, Bradley, Calhoun, Clay, Cleveland, Craighead and 20 more	5 hr
Feb 26, 10:36 PM CST	Mesoscale Discussion	SPC	Arkansas, Baxter, Bradley, Calhoun, Clark, Clay and 46 more	114 min
Feb 27, 1:45 AM CST	Mesoscale Discussion	SPC	Arkansas, Cleveland, Craighead, Crittenden, Cross, Dallas and 18 more	30 min
Feb 27, 2:40 PM CST	Mesoscale Discussion	SPC	Arkansas, Clark, Cleveland, Conway, Dallas, Desha and 21 more	65 min

Nearby

Mesoscale Discussions in Mississippi, 2009 Mesoscale Discussions in Arkansas, 2009 Mesoscale Discussions in Alabama, 2009 Every mesoscale discussion in 2009

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.