Alert archive / Texas / Mesoscale Discussions in 2019

Mesoscale Discussion 239

March 25, 201912 parishes in Louisiana; 15 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 25, 2019, 12:10 PM CDT for 12 parishes in Louisiana; 15 counties in Texas. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Mar 25, 2019, 12:10 PM CDT (17:10 UTC)
Expired: Mar 25, 2019, 2:45 PM CDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 27 counties

Acadia Parish, LA, Allen Parish, LA, Beauregard Parish, LA, Calcasieu Parish, LA, Cameron Parish, LA, Evangeline Parish, LA, Iberia Parish, LA, Jefferson Davis Parish, LA, Lafayette Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, Vermilion Parish, LA, Brazoria County, TX, Chambers County, TX, Galveston County, TX, Hardin County, TX, Harris County, TX, Jasper County, TX, Jefferson County, TX, Liberty County, TX, Montgomery County, TX, Newton County, TX, Orange County, TX, Polk County, TX, San Jacinto County, TX, Tyler County, TX, Walker County, TX

The radar

The Lake Charles radar (KLCH), 67 km from the middle of the area, began a volume at 17:11 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, 5.2 hours before the alert went out and 68 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: 295 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 515 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 109 m²/s²
0-3 km storm-relative helicity: 164 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.1

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
Mar 25, 1:47 AM CDT	Mesoscale Discussion	SPC	Bossier, Caddo, Webster	88 min
Mar 24, 10:11 PM CDT	Mesoscale Discussion	SPC	Bowie, Camp, Cass, Dallas, Delta, Franklin and 16 more	2 hr

Nearby

Mesoscale Discussions in Texas, 2019 Mesoscale Discussions in Louisiana, 2019 Every mesoscale discussion in 2019

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.