Alert archive / Louisiana / Mesoscale Discussions in 2015

Mesoscale Discussion 296

April 14, 20156 parishes in Louisiana; 5 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 14, 2015, 3:19 PM CDT for 6 parishes in Louisiana; 5 counties in Texas. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: Apr 14, 2015, 3:19 PM CDT (20:19 UTC)
Expired: Apr 14, 2015, 4:15 PM CDT
In force: 56 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

Counties De Soto Parish, LA, Grant Parish, LA, Natchitoches Parish, LA, Red River Parish, LA, Sabine Parish, LA, Winn Parish, LA, Panola County, TX, Rusk County, TX, Sabine County, TX, San Augustine County, TX, Shelby County, TX

The radar

The Ft Polk radar (KPOE), 85 km from the middle of the area, began a volume at 20:19 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 nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 8.3 hours before the alert went out and 177 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: 986 J/kg
Mixed-layer CIN: -77 J/kg
Mixed-layer LCL: 1032 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 31 m²/s²
0-3 km storm-relative helicity: 123 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 3.0

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 13, 7:54 PM CDT	Mesoscale Discussion	SPC	Anderson, Bell, Bosque, Brown, Comanche, Coryell and 11 more	2 hr
Apr 13, 11:30 PM CDT	Mesoscale Discussion	SPC	Atascosa, Brooks, Dimmit, Duval, Frio, Jim Hogg and 7 more	3 hr

Nearby

Mesoscale Discussions in Louisiana, 2015 Mesoscale Discussions in Texas, 2015 Every mesoscale discussion in 2015

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.