Alert archive / Louisiana / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 91, NWS New Orleans, LA

July 5, 2018Lafourche Parish, Louisiana

NWS New Orleans, LA issued this severe thunderstorm warning at Jul 5, 2018, 12:52 PM CDT for Lafourche Parish, Louisiana. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 5, 2018, 12:52 PM CDT (17:52 UTC)
Expired: Jul 5, 2018, 1:15 PM CDT
In force: 23 min
Issued by: NWS New Orleans, LA
Area: Storm-based polygon
Tornado: Possible
Hail: 0.75 in
Wind: 60.0 mph

County Lafourche Parish, LA

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 12:00Z, 5.9 hours before the alert went out and 279 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: 480 J/kg
Mixed-layer CIN: -104 J/kg
Mixed-layer LCL: 1069 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 23 m²/s²
Significant tornado parameter: -0.0
Supercell composite: -0.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS New Orleans, LA wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 5, 8:59 AM CDT, 3 hours 53 minutes earlier.

Area forecast discussion, Jul 5, 8:59 AM CDT, 3 hours 53 minutes before

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Hazardous weather outlook, Jul 5, 3:37 AM CDT, 9 hours 15 minutes before

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In the hours before

Special weather statement, Jul 5, 12:46 PM CDT, 6 minutes before

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The office that day

Everything else NWS New Orleans, LA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 4, 9:58 PM CDT	Special Marine Warning	LIX		62 min
Jul 4, 10:53 PM CDT	Special Marine Warning	LIX		43 min
Jul 5, 10:03 AM CDT	Special Marine Warning	LIX		57 min
Jul 5, 11:12 AM CDT	Special Marine Warning	LIX		63 min
Jul 5, 11:22 AM CDT	Special Marine Warning	LIX		53 min
Jul 5, 11:53 AM CDT	Special Marine Warning	LIX		22 min
Jul 5, 12:46 PM CDT	Special Weather Statement	LIX	Lafourche	44 min
Jul 5, 12:55 PM CDT	Special Weather Statement	LIX	Saint Charles	35 min
Jul 5, 3:06 PM CDT	Areal Flood Advisory	LIX	Ascension, East Baton Rouge, Iberville, West Baton Rouge	54 min
Jul 5, 3:38 PM CDT	Special Marine Warning	LIX		52 min
Jul 5, 5:15 PM CDT	Special Weather Statement	LIX	Saint Tammany	30 min
Jul 5, 3:40 PM CDT	Special Weather Statement	LIX	Harrison	50 min

Nearby

Severe Thunderstorm Warnings in Louisiana, 2018 Every severe thunderstorm warning in 2018

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.