Alert archive / Louisiana / Mesoscale Discussions in 2023

Mesoscale Discussion 99

January 24, 202312 parishes in Louisiana

The Storm Prediction Center issued this mesoscale discussion at Jan 24, 2023, 6:11 PM CST for 12 parishes in Louisiana. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jan 24, 2023, 6:11 PM CST (00:11 UTC)
Expired
Jan 24, 2023, 8:15 PM CST
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Tornado watch 28

Counties Acadia Parish, LA, Avoyelles Parish, LA, Iberia Parish, LA, Iberville Parish, LA, Lafayette Parish, LA, Pointe Coupee Parish, LA, Saint Landry Parish, LA, Saint Martin Parish, LA, St. Mary Parish, LA, Vermilion Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA

The radar

The Lake Charles radar (KLCH), 94 km from the middle of the area, began a volume at 00:16 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

Slidell Radar S, LA (KSIL), launched 00:00Z, 0.2 hours before the alert went out and 253 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-pSkew-T log-p diagram, Slidell Radar S, LA at 00:00Z on 2023-01-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Slidell Radar S, LA at 00:00Z on 2023-01-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 805 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
550 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
805 m²/s²
0-3 km storm-relative helicity
1093 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

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.

IssuedProductOfficeCountiesLasted
Jan 24, 10:12 PM CSTMesoscale DiscussionSPCJefferson, Lafourche, Orleans, Saint Bernard, Saint Tammany93 min

Nearby

Mesoscale Discussions in Louisiana, 2023Every mesoscale discussion in 2023

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.