Alert archive / Mississippi / Mesoscale Discussions in 2005

Mesoscale Discussion 671

April 22, 200513 parishes in Louisiana; 16 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at Apr 22, 2005, 10:29 PM CDT for 13 parishes in Louisiana; 16 counties in Mississippi. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued: Apr 22, 2005, 10:29 PM CDT (03:29 UTC)
Expired: Apr 23, 2005, 12:00 AM CDT
In force: 91 min
Issued by: the Storm Prediction Center

All 29 counties

Ascension Parish, LA, Concordia Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Livingston Parish, LA, Pointe Coupee Parish, LA, Saint Helena Parish, LA, Saint Martin Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Adams County, MS, Amite County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, Jefferson Davis County, MS, Lamar County, MS, Lawrence County, MS, Lincoln County, MS, Marion County, MS, Pearl River County, MS, Pike County, MS, Simpson County, MS, Walthall County, MS, Wilkinson County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 00:00Z, 3.5 hours before the alert went out and 135 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: 2091 J/kg
Mixed-layer CIN: -11 J/kg
Mixed-layer LCL: 1047 m above ground
0-6 km bulk shear: 58 kt
0-1 km storm-relative helicity: 180 m²/s²
0-3 km storm-relative helicity: 207 m²/s²
Significant tornado parameter: 2.4
Supercell composite: 7.6

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
Apr 22, 11:20 PM CDT	Mesoscale Discussion	SPC	Ascension, Iberville, Livingston	55 min
Apr 22, 8:28 PM CDT	Mesoscale Discussion	SPC	Clarke, Forrest, George, Greene, Jasper, Jones and 4 more	2 hr
Apr 22, 8:50 PM CDT	Severe Thunderstorm Watch	SPC	George, Greene, Jones, Perry, Wayne	5 hr
Apr 22, 11:14 PM CDT	Mesoscale Discussion	SPC	Greene, Wayne	91 min

Nearby

Mesoscale Discussions in Mississippi, 2005 Mesoscale Discussions in Louisiana, 2005 Every mesoscale discussion in 2005

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.