Alert archive / Louisiana / Flash Flood Warnings in 2023

Flash Flood Warning 18, NWS New Orleans, LA

April 29, 2023Saint Tammany Parish, Louisiana; Hancock County, Mississippi

NWS New Orleans, LA issued this flash flood warning at Apr 29, 2023, 3:36 PM CDT for Saint Tammany Parish, Louisiana; Hancock County, Mississippi. It was in force for 103 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
Apr 29, 2023, 3:36 PM CDT (20:36 UTC)
Expired
Apr 29, 2023, 5:19 PM CDT
In force
103 min
Issued by
NWS New Orleans, LA
Area
Storm-based polygon
Flood severity
None

Counties Saint Tammany Parish, LA, Hancock County, MS

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 8.6 hours before the alert went out and 216 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, Jackson, MS at 12:00Z on 2023-04-29Temperature 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, Jackson, MS at 12:00Z on 2023-04-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 251 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
1508 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
251 m²/s²
0-3 km storm-relative helicity
325 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 29, 4:17 AM CDTWind AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Bernard, Saint John the Baptist27 hr
Apr 29, 6:56 AM CDTSpecial Marine WarningLIX94 min
Apr 29, 8:30 AM CDTSpecial Marine WarningLIX90 min
Apr 29, 3:09 PM CDTAreal Flood AdvisoryLIXSaint Tammany27 min

Nearby

Flash Flood Warnings in Louisiana, 2023Flash Flood Warnings in Mississippi, 2023Every flash flood warning 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.