Alert archive / Louisiana / Flash Flood Warnings in 1999

Flash Flood Warning 17, NWS New Orleans, LA

August 9, 1999Jefferson Parish, Orleans Parish, Louisiana

NWS New Orleans, LA issued this flash flood warning at Aug 9, 1999, 4:49 PM CDT for Jefferson Parish, Orleans Parish, Louisiana. It was in force for 91 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
Aug 9, 1999, 4:49 PM CDT (21:49 UTC)
Expired
Aug 9, 1999, 6:20 PM CDT
In force
91 min
Issued by
NWS New Orleans, LA
Area
Whole counties

Counties Jefferson Parish, LA, Orleans Parish, LA

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 9.8 hours before the alert went out and 272 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 1999-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3127 joules per kilogram.LCLLFCEL10008507005003002001001 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 1999-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 10 square meters per square second.193958Sfc1 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
3127 J/kg
Mixed-layer CIN
-56 J/kg
Mixed-layer LCL
1041 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
10 m²/s²
0-3 km storm-relative helicity
24 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 1:44 PM CDTSevere Thunderstorm WarningLIXJefferson31 min
Aug 9, 2:10 PM CDTSevere Thunderstorm WarningLIXPlaquemines, Saint Bernard30 min
Aug 9, 2:21 PM CDTSevere Thunderstorm WarningLIXSaint Tammany34 min
Aug 9, 4:55 PM CDTSevere Thunderstorm WarningLIXSaint Charles, Saint John the Baptist65 min
Aug 9, 4:55 PM CDTSevere Thunderstorm WarningLIXJefferson65 min
Aug 9, 6:14 PM CDTSevere Thunderstorm WarningLIXEast Feliciana36 min
Aug 9, 6:38 PM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, Iberville, West Baton Rouge47 min
Aug 9, 2:49 PM CDTSevere Thunderstorm WarningLIXPearl River31 min

Nearby

Flash Flood Warnings in Louisiana, 1999Every flash flood warning in 1999

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.