Alert archive / Mississippi / Mesoscale Discussions in 2004

Mesoscale Discussion 549

May 1, 20049 parishes in Louisiana; 11 counties in Mississippi

The Storm Prediction Center issued this mesoscale discussion at May 1, 2004, 1:45 PM CDT for 9 parishes in Louisiana; 11 counties in Mississippi. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: May 1, 2004, 1:45 PM CDT (18:45 UTC)
Expired: May 1, 2004, 4:15 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center

Counties East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Livingston Parish, LA, Saint Helena Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, Amite County, MS, Forrest County, MS, George County, MS, Greene County, MS, Lamar County, MS, Marion County, MS, Pearl River County, MS, Perry County, MS, Pike County, MS, Stone County, MS, Walthall County, MS

The watches that followed

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

Severe Thunderstorm Watch 145May 1, 4:00 PM CDT

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 6.8 hours before the alert went out and 85 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: 332 J/kg
Mixed-layer CIN: -166 J/kg
Mixed-layer LCL: 931 m above ground
0-6 km bulk shear: 13 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 76 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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
Apr 30, 11:56 PM CDT	Mesoscale Discussion	SPC	Beauregard, Calcasieu, Cameron, Jefferson Davis	94 min
May 1, 12:50 AM CDT	Severe Thunderstorm Watch	SPC	Bossier, Caddo	6 hr
May 1, 2:38 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Caldwell, Claiborne, De Soto and 10 more	37 min
May 1, 3:10 AM CDT	Severe Thunderstorm Watch	SPC	Bienville, Bossier, Claiborne, De Soto, Jackson, Lincoln and 7 more	6 hr
May 1, 5:13 AM CDT	Mesoscale Discussion	SPC	Bienville, Bossier, Caddo, Claiborne, De Soto, Jackson and 6 more	92 min
May 1, 7:24 AM CDT	Mesoscale Discussion	SPC	Natchitoches, Sabine, Winn	96 min
May 1, 9:45 AM CDT	Tornado Watch	SPC	Allen, Beauregard, Calcasieu, Cameron, Jefferson Davis, Vernon	5 hr
May 1, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	Washington	5 hr

Nearby

Mesoscale Discussions in Mississippi, 2004 Mesoscale Discussions in Louisiana, 2004 Every mesoscale discussion in 2004

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.