Alert archive / Louisiana / Special Weather Statements in 2021

Special Weather Statement, NWS New Orleans, LA

May 11, 2021Tangipahoa Parish, Louisiana

NWS New Orleans, LA issued this special weather statement at May 11, 2021, 9:21 AM CDT for Tangipahoa Parish, Louisiana. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
May 11, 2021, 9:21 AM CDT (14:21 UTC)
Expired
May 11, 2021, 10:00 AM CDT
In force
39 min
Issued by
NWS New Orleans, LA

County Tangipahoa Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 2.4 hours before the alert went out and 66 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 12:00Z on 2021-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2600 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, Slidell Radar S, LA at 12:00Z on 2021-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 square meters per square second.19395878Sfc1 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
2600 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
469 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
56 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.1

Open this sounding in Storm Lab

The text

As transmitted.

195 
WWUS84 KLIX 111421
SPSLIX

Special Weather Statement
National Weather Service New Orleans LA
921 AM CDT Tue May 11 2021

LAZ039-071-072-075-111500-
Washington-Northern Tangipahoa-Northwest St. Tammany-Southern
Tangipahoa-
921 AM CDT Tue May 11 2021

...A STRONG THUNDERSTORM WILL AFFECT NORTHWESTERN ST. TAMMANY...
CENTRAL TANGIPAHOA AND SOUTHWESTERN WASHINGTON PARISHES...

At 921 AM CDT, a strong thunderstorm was located near Robert, or 10
miles west of Covington, moving north at 25 mph.

Wind gusts up to 50 mph are possible with this storm.

Locations impacted include...
Hammond, Franklinton, Amite, Ponchatoula, Amite City, Independence,
Roseland, Folsom, Enon, Wilmer, Natalbany, Robert and Tickfaw.

This includes the following Interstates...
 Interstate 12 between mile markers 39 and 57.
 Interstate 55 in Louisiana between mile markers 25 and 26, and
between mile markers 46 and 55.

LAT...LON 3042 9020 3042 9046 3085 9057 3084 8992
TIME...MOT...LOC 1421Z 174DEG 22KT 3052 9027 

$$

MEFFER

The office that day

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

IssuedProductOfficeCountiesLasted
May 10, 8:57 PM CDTRiver Flood WarningLIXTangipahoa5 days
May 10, 8:58 PM CDTRiver Flood WarningLIXSaint Tammany61 hr
May 10, 9:33 PM CDTAreal Flood AdvisoryLIXLafourche, Terrebonne48 min
May 11, 3:11 AM CDTFlash Flood WatchLIXAssumption, East Baton Rouge, East Feliciana, Iberville, Orleans, Pointe Coupee and 9 more39 hr
May 11, 7:11 AM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines32 min
May 11, 7:43 AM CDTFlash Flood WarningLIXJefferson, Orleans, Plaquemines77 min
May 11, 7:49 AM CDTAreal Flood AdvisoryLIXJefferson, Orleans116 min
May 11, 8:49 AM CDTAreal Flood AdvisoryLIXOrleans, Saint Tammany116 min
May 11, 9:14 AM CDTSevere Thunderstorm WarningLIXSaint Tammany, Washington29 min
May 11, 9:17 AM CDTSevere Thunderstorm WarningLIXEast Baton Rouge, East Feliciana, Livingston, Saint Helena43 min
May 11, 9:25 AM CDTSpecial Marine WarningLIX65 min
May 11, 9:53 AM CDTSpecial Weather StatementLIXEast Baton Rouge, Iberville, West Baton Rouge67 min
May 11, 10:06 AM CDTRiver Flood WarningLIXSaint Tammany6 days
May 11, 10:20 AM CDTAreal Flood AdvisoryLIXAscension, Assumption, East Baton Rouge, Iberville, Livingston, Saint James and 1 more115 min
May 11, 10:25 AM CDTSpecial Marine WarningLIX65 min
May 11, 10:26 AM CDTRiver Flood WarningLIXSaint Tammany61 hr
May 11, 10:26 AM CDTRiver Flood WarningLIXSaint Helena24 hr
May 11, 10:34 AM CDTSpecial Weather StatementLIXWashington56 min
May 11, 11:25 AM CDTAreal Flood AdvisoryLIXSaint Tammany, Tangipahoa, Washington3 hr
May 11, 11:38 AM CDTSpecial Marine WarningLIX67 min
May 11, 11:50 AM CDTAreal Flood WarningLIXSaint Tammany, Tangipahoa115 min
May 11, 12:10 PM CDTSpecial Weather StatementLIXSaint Charles35 min
May 11, 12:28 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Bernard, Saint Charles, Saint John the Baptist2 hr
May 11, 12:35 PM CDTSpecial Marine WarningLIX55 min
May 11, 1:04 PM CDTTornado WarningLIXOrleans14 min
May 11, 1:24 PM CDTAreal Flood AdvisoryLIXSaint Tammany66 min
May 11, 3:05 PM CDTSpecial Marine WarningLIX55 min
May 11, 3:52 PM CDTSpecial Marine WarningLIX53 min
May 11, 9:47 AM CDTSpecial Weather StatementLIXPearl River43 min
May 11, 10:10 AM CDTRiver Flood WarningLIXPearl River34 hr
May 11, 10:10 AM CDTRiver Flood WarningLIXPearl River33 hr
May 11, 10:13 AM CDTSpecial Weather StatementLIXHancock47 min
May 11, 10:54 AM CDTSevere Thunderstorm WarningLIXJackson51 min
May 11, 10:57 AM CDTSevere Thunderstorm WarningLIXHarrison, Jackson48 min
May 11, 11:42 AM CDTSpecial Weather StatementLIXJackson63 min

Nearby

Special Weather Statements in Louisiana, 2021Every special weather statement in 2021

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.