Alert archive / Louisiana / Heat Advisories in 2021

Heat Advisory 26, NWS New Orleans, LA

September 7, 20215 parishes in Louisiana

NWS New Orleans, LA issued this heat advisory at Sep 7, 2021, 3:47 AM CDT for 5 parishes in Louisiana. It took effect at Sep 7, 2021, 11:00 AM CDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Sep 7, 2021, 3:47 AM CDT (08:47 UTC)
In effect from
Sep 7, 2021, 11:00 AM CDT
Expired
Sep 7, 2021, 5:00 PM CDT
In force
6 hr
Issued by
NWS New Orleans, LA

Counties Assumption Parish, LA, Iberville Parish, LA, Orleans Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 00:00Z, 8.8 hours before the alert went out and 100 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 2021-09-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1597 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 00:00Z on 2021-09-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 15 square meters per square second.1939Sfc1 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
1597 J/kg
Mixed-layer CIN
-50 J/kg
Mixed-layer LCL
976 m above ground
0-6 km bulk shear
12 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
25 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this heat advisory 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 heat advisory went out at Sep 6, 11:16 PM CDT, 4 hours 31 minutes earlier.

Area forecast discussion, Sep 6, 11:16 PM CDT, 4 hours 31 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Sep 7, 4:13 AM CDTSpecial Marine WarningLIX67 min
Sep 7, 3:37 PM CDTAreal Flood AdvisoryLIXJefferson, Orleans, Plaquemines, Saint Charles95 min
Sep 7, 3:52 PM CDTHeat AdvisoryLIXSaint James, Saint John the Baptist25 hr
Sep 7, 3:57 PM CDTSpecial Weather StatementLIXSaint Tammany78 min
Sep 7, 4:52 PM CDTAreal Flood AdvisoryLIXAscension, Assumption, Saint James35 min
Sep 7, 2:02 PM CDTSpecial Weather StatementLIXHarrison58 min
Sep 7, 3:27 PM CDTSpecial Weather StatementLIXHancock78 min

Nearby

Heat Advisories in Louisiana, 2021Every heat advisory 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.