Alert archive / Louisiana / Excessive Heat Warnings in 2021

Excessive Heat Warning 2, NWS New Orleans, LA

July 30, 202115 parishes in Louisiana; 5 counties in Mississippi

NWS New Orleans, LA issued this excessive heat warning at Jul 30, 2021, 3:55 PM CDT for 15 parishes in Louisiana; 5 counties in Mississippi. It took effect at Jul 31, 2021, 9:00 AM CDT. It was in force for 7 hr. 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 30, 2021, 3:55 PM CDT (20:55 UTC)
In effect from
Jul 31, 2021, 9:00 AM CDT
Expired
Jul 31, 2021, 3:57 PM CDT
In force
7 hr
Issued by
NWS New Orleans, LA

Counties Assumption Parish, LA, East Baton Rouge Parish, LA, East Feliciana Parish, LA, Iberville Parish, LA, Orleans Parish, LA, Pointe Coupee Parish, LA, Saint Bernard Parish, LA, Saint Helena Parish, LA, Saint James Parish, LA, Saint John the Baptist Parish, LA, Saint Tammany Parish, LA, Tangipahoa Parish, LA, Washington Parish, LA, West Baton Rouge Parish, LA, West Feliciana Parish, LA, Amite County, MS, Pearl River County, MS, Pike County, MS, Walthall County, MS, Wilkinson County, MS

The nearest sounding before it

Slidell Radar S, LA (KSIL), launched 12:00Z, 8.9 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 12:00Z on 2021-07-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1204 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°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 2021-07-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 18 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
1204 J/kg
Mixed-layer CIN
-67 J/kg
Mixed-layer LCL
1075 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
18 m²/s²
0-3 km storm-relative helicity
23 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

430 
WWUS74 KLIX 302055
NPWLIX

URGENT - WEATHER MESSAGE
National Weather Service New Orleans LA
355 PM CDT Fri Jul 30 2021

LAZ037-039-050-058-060-061-063-064-071-072-075>078-MSZ070-071-077-
080>082-310500-
/O.UPG.KLIX.EH.A.0001.210731T1400Z-210801T0000Z/
/O.NEW.KLIX.EH.W.0002.210731T1400Z-210801T0000Z/
/O.CON.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
St. Helena-Washington-Livingston-St. John The Baptist-St. Charles-
Upper Jefferson-Upper Plaquemines-Upper St. Bernard-
Northern Tangipahoa-Southern Tangipahoa-Northwest St. Tammany-
Southeast St. Tammany-Western Orleans-Eastern Orleans-Pike-
Walthall-Pearl River-Hancock-Harrison-Jackson-
Including the cities of Darlington, Easleyville, Greensburg, 
Montpelier, Bogalusa, Enon, Franklinton, Denham Springs, Watson, 
Walker, Laplace, Reserve, Destrehan, Norco, Metairie, Kenner, 
Belle Chasse, Chalmette, Violet, Amite, Kentwood, Roseland, 
Wilmer, Hammond, Robert, Ponchatoula, Mandeville, Covington, 
Lacombe, Slidell, New Orleans, East New Orleans, McComb, Dexter, 
Salem, Tylertown, Crossroads, McNeil, Poplarville, Picayune, 
Bay St. Louis, Waveland, Diamondhead, Gulfport, Pascagoula, 
Ocean Springs, Moss Point, Gautier, and St. Martin
355 PM CDT Fri Jul 30 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...EXCESSIVE HEAT WARNING IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...

* WHAT...Dangerously hot conditions with heat index values in 
  excess of 112 degrees possible.

* WHERE...Portions of southeast and southern Mississippi and 
  southeast Louisiana.

* WHEN...9 AM to 7 PM each day

* IMPACTS...Extreme heat and humidity will significantly increase
  the potential for heat related illnesses, particularly for those
  working or participating in outdoor activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ036-MSZ068-069-310500-
/O.UPG.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
/O.NEW.KLIX.EH.W.0002.210731T1400Z-210801T0000Z/
/O.CON.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
East Feliciana-Wilkinson-Amite-
Including the cities of Jackson, Clinton, Felps, Centreville, 
Dolorosa, Fort Adams, Woodville, Gillsberg, Gloster, Smithdale, 
and Liberty
355 PM CDT Fri Jul 30 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...EXCESSIVE HEAT WARNING IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...

* WHAT...Dangerously hot conditions with heat index values in
  excess of 112 possible.

* WHERE...In Mississippi, Wilkinson and Amite Counties. In 
  Louisiana, East Feliciana Parish.

* WHEN...9 AM through 7 PM each day

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ049-056-057-059-065-070-310500-
/O.UPG.KLIX.EH.A.0001.210731T1400Z-210801T0000Z/
/O.EXA.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
/O.CON.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
Ascension-Assumption-St. James-Upper Lafourche-Upper Terrebonne-
Lower St. Bernard-
Including the cities of Gonzales, Donaldsonville, Prairieville, 
Pierre Part, Labadieville, Paincourtville, Convent, Lutcher, 
Gramercy, Thibodaux, Raceland, Larose, Houma, Bayou Cane, 
and Yscloskey
355 PM CDT Fri Jul 30 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...HEAT ADVISORY IN EFFECT FROM 9 AM TO 7 PM CDT SATURDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot
  conditions with heat index values in excess of 112 possible. 
  For the Heat Advisory, heat index values up to 109 expected.

* WHERE...Upper Terrebonne County, and Ascension, Assumption, 
  St. James, Upper Lafourche and Lower St. Bernard Parishes.

* WHEN...For the Excessive Heat Warning, until 7 PM CDT this 
  evening. For the Heat Advisory, from 9 AM to 7 PM CDT Saturday.

* IMPACTS...Extreme heat and humidity will significantly increase
  the potential for heat related illnesses, particularly for those
  working or participating in outdoor activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ034-035-046>048-310500-
/O.CON.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
/O.CON.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
Pointe Coupee-West Feliciana-Iberville-West Baton Rouge-
East Baton Rouge-
Including the cities of New Roads, Lettsworth, Livonia, Spillman,
St. Francisville, Wakefield, Bayou Sorrel, Plaquemine, 
White Castle, Port Allen, Addis, Brusly, and Baton Rouge
355 PM CDT Fri Jul 30 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...HEAT ADVISORY REMAINS IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot
  conditions with heat index values in excess of 112 degrees
  possible. For the Heat Advisory, heat index values up to 109 
  expected.

* WHERE...Pointe Coupee, West Feliciana, Iberville, West Baton
  Rouge and East Baton Rouge Parishes in southeast Louisiana.

* WHEN...From 9am until 7pm each day.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ066>069-310500-
/O.EXA.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
/O.CON.KLIX.HT.Y.0011.000000T0000Z-210731T0000Z/
Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-
Including the cities of Chauvin, Cocodrie, Dulac, Montegut, 
Galliano, Cut Off, Golden Meadow, Leeville, Buras, 
Pointe A La Hache, Port Sulphur, Boothville, Venice, Empire, 
and Myrtle Grove
355 PM CDT Fri Jul 30 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 9 AM TO 7 PM CDT SATURDAY...

* WHAT...Heat index values up to 108 possible.

* WHERE...Lower Terrebonne, Lower Lafourche, Lower Jefferson and 
  Lower Plaquemines Parishes.

* WHEN...From 9am until 7pm each day.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

95/DM
4 follow-up statements
497 
WWUS74 KLIX 310010
NPWLIX

URGENT - WEATHER MESSAGE
National Weather Service New Orleans LA
710 PM CDT Fri Jul 30 2021

LAZ036-037-039-050-058-060-061-063-064-071-072-075>078-MSZ068>071-
077-080>082-310930-
/O.EXP.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
/O.CON.KLIX.EH.W.0002.210731T1400Z-210801T0000Z/
East Feliciana-St. Helena-Washington-Livingston-
St. John The Baptist-St. Charles-Upper Jefferson-
Upper Plaquemines-Upper St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Northwest St. Tammany-Southeast St. Tammany-
Western Orleans-Eastern Orleans-Wilkinson-Amite-Pike-Walthall-
Pearl River-Hancock-Harrison-Jackson-
Including the cities of Jackson, Clinton, Felps, Darlington, 
Easleyville, Greensburg, Montpelier, Bogalusa, Enon, Franklinton,
Denham Springs, Watson, Walker, Laplace, Reserve, Destrehan, 
Norco, Metairie, Kenner, Belle Chasse, Chalmette, Violet, Amite, 
Kentwood, Roseland, Wilmer, Hammond, Robert, Ponchatoula, 
Mandeville, Covington, Lacombe, Slidell, New Orleans, 
East New Orleans, Centreville, Dolorosa, Fort Adams, Woodville, 
Gillsberg, Gloster, Smithdale, Liberty, McComb, Dexter, Salem, 
Tylertown, Crossroads, McNeil, Poplarville, Picayune, 
Bay St. Louis, Waveland, Diamondhead, Gulfport, Pascagoula, 
Ocean Springs, Moss Point, Gautier, and St. Martin
710 PM CDT Fri Jul 30 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...
...EXCESSIVE HEAT WARNING TODAY HAS EXPIRED...

* WHAT...Dangerously hot conditions with heat index values up to
  113 expected.

* WHERE...Portions of southeast and southern Mississippi and 
  southeast Louisiana.

* WHEN...9 AM to 7 PM Saturday.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ034-035-046>049-056-057-059-065-070-310930-
/O.EXP.KLIX.EH.W.0001.000000T0000Z-210731T0000Z/
/O.CON.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
Pointe Coupee-West Feliciana-Iberville-West Baton Rouge-
East Baton Rouge-Ascension-Assumption-St. James-Upper Lafourche-
Upper Terrebonne-Lower St. Bernard-
Including the cities of New Roads, Lettsworth, Livonia, Spillman,
St. Francisville, Wakefield, Bayou Sorrel, Plaquemine, 
White Castle, Port Allen, Addis, Brusly, Baton Rouge, Gonzales, 
Donaldsonville, Prairieville, Pierre Part, Labadieville, 
Paincourtville, Convent, Lutcher, Gramercy, Thibodaux, Raceland, 
Larose, Houma, Bayou Cane, and Yscloskey
710 PM CDT Fri Jul 30 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...
...EXCESSIVE HEAT WARNING HAS EXPIRED TODAY...

* WHAT...Heat index values up to 109 expected.

* WHERE...Upper Terrebonne County, and Ascension, Assumption, 
  St. James, Upper Lafourche and Lower St. Bernard Parishes.

* WHEN...9 AM to 7 PM CDT Saturday.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ066>069-310930-
/O.EXP.KLIX.HT.Y.0011.000000T0000Z-210731T0000Z/
/O.CON.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-
Including the cities of Chauvin, Cocodrie, Dulac, Montegut, 
Galliano, Cut Off, Golden Meadow, Leeville, Buras, 
Pointe A La Hache, Port Sulphur, Boothville, Venice, Empire, 
and Myrtle Grove
710 PM CDT Fri Jul 30 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 9 AM TO 7 PM CDT
SATURDAY...
...HEAT ADVISORY HAS EXPIRED TODAY...

* WHAT...Heat index values up to 109 expected.

* WHERE...Lower Terrebonne, Lower Lafourche, Lower Jefferson and 
  Lower Plaquemines Parishes.

* WHEN...From 9 AM until 7 PM.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
049 
WWUS74 KLIX 310855
NPWLIX

URGENT - WEATHER MESSAGE
National Weather Service New Orleans LA
355 AM CDT Sat Jul 31 2021

LAZ034-035-046>049-056-057-059-065-311700-
/O.UPG.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
/O.EXA.KLIX.EH.W.0002.210731T1400Z-210801T0000Z/
Pointe Coupee-West Feliciana-Iberville-West Baton Rouge-
East Baton Rouge-Ascension-Assumption-St. James-Upper Lafourche-
Upper Terrebonne-
Including the cities of New Roads, Lettsworth, Livonia, Spillman,
St. Francisville, Wakefield, Bayou Sorrel, Plaquemine, 
White Castle, Port Allen, Addis, Brusly, Baton Rouge, Gonzales, 
Donaldsonville, Prairieville, Pierre Part, Labadieville, 
Paincourtville, Convent, Lutcher, Gramercy, Thibodaux, Raceland, 
Larose, Houma, and Bayou Cane
355 AM CDT Sat Jul 31 2021

...EXCESSIVE HEAT WARNING IN EFFECT FROM 9 AM THIS MORNING TO
7 PM CDT THIS EVENING...

* WHAT...Dangerously hot conditions with heat index values 110 to
  to 115 expected.

* WHERE...Upper Terrebonne County, and Pointe Coupee, West 
  Feliciana, Iberville, West Baton Rouge, East Baton Rouge, 
  Ascension, Assumption, St. James and Upper Lafourche Parishes.

* WHEN...From 9 AM this morning to 7 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ036-037-039-050-058-060-061-063-064-071-072-075>078-MSZ068>071-
077-080>082-311700-
/O.CON.KLIX.EH.W.0002.210731T1400Z-210801T0000Z/
East Feliciana-St. Helena-Washington-Livingston-
St. John The Baptist-St. Charles-Upper Jefferson-
Upper Plaquemines-Upper St. Bernard-Northern Tangipahoa-
Southern Tangipahoa-Northwest St. Tammany-Southeast St. Tammany-
Western Orleans-Eastern Orleans-Wilkinson-Amite-Pike-Walthall-
Pearl River-Hancock-Harrison-Jackson-
Including the cities of Jackson, Clinton, Felps, Darlington, 
Easleyville, Greensburg, Montpelier, Bogalusa, Enon, Franklinton,
Denham Springs, Watson, Walker, Laplace, Reserve, Destrehan, 
Norco, Metairie, Kenner, Belle Chasse, Chalmette, Violet, Amite, 
Kentwood, Roseland, Wilmer, Hammond, Robert, Ponchatoula, 
Mandeville, Covington, Lacombe, Slidell, New Orleans, 
East New Orleans, Centreville, Dolorosa, Fort Adams, Woodville, 
Gillsberg, Gloster, Smithdale, Liberty, McComb, Dexter, Salem, 
Tylertown, Crossroads, McNeil, Poplarville, Picayune, 
Bay St. Louis, Waveland, Diamondhead, Gulfport, Pascagoula, 
Ocean Springs, Moss Point, Gautier, and St. Martin
355 AM CDT Sat Jul 31 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT FROM 9 AM THIS
MORNING TO 7 PM CDT THIS EVENING...

* WHAT...Dangerously hot conditions with heat index values 110 to
  115 expected.

* WHERE...Portions of southeast and southern Mississippi and 
  southeast Louisiana.

* WHEN...9 AM to 7 PM today.

* IMPACTS...Extreme heat and humidity will significantly 
  increase the potential for heat related illnesses, 
  particularly for those working or participating in outdoor 
  activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ066>070-311700-
/O.CON.KLIX.HT.Y.0010.210731T1400Z-210801T0000Z/
Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-
Including the cities of Chauvin, Cocodrie, Dulac, Montegut, 
Galliano, Cut Off, Golden Meadow, Leeville, Buras, 
Pointe A La Hache, Port Sulphur, Boothville, Venice, Empire, 
Myrtle Grove, and Yscloskey
355 AM CDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 9 AM THIS MORNING TO 7 PM
CDT THIS EVENING...

* WHAT...Heat index values up to 110 expected.

* WHERE...Lower Terrebonne, Lower Lafourche, Lower Jefferson and 
  Lower Plaquemines Parishes.

* WHEN...From 9 AM until 7 PM today.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
895 
WWUS74 KLIX 311616
NPWLIX

URGENT - WEATHER MESSAGE
National Weather Service New Orleans LA
1116 AM CDT Sat Jul 31 2021

LAZ034>037-039-046>050-056>061-063>065-071-072-075>078-MSZ068>071-
077-080>082-010000-
/O.CON.KLIX.EH.W.0002.000000T0000Z-210801T0000Z/
Pointe Coupee-West Feliciana-East Feliciana-St. Helena-Washington-
Iberville-West Baton Rouge-East Baton Rouge-Ascension-Livingston-
Assumption-St. James-St. John The Baptist-Upper Lafourche-
St. Charles-Upper Jefferson-Upper Plaquemines-Upper St. Bernard-
Upper Terrebonne-Northern Tangipahoa-Southern Tangipahoa-
Northwest St. Tammany-Southeast St. Tammany-Western Orleans-
Eastern Orleans-Wilkinson-Amite-Pike-Walthall-Pearl River-Hancock-
Harrison-Jackson-
Including the cities of New Roads, Lettsworth, Livonia, Spillman,
St. Francisville, Wakefield, Jackson, Clinton, Felps, Darlington,
Easleyville, Greensburg, Montpelier, Bogalusa, Enon, Franklinton,
Bayou Sorrel, Plaquemine, White Castle, Port Allen, Addis, 
Brusly, Baton Rouge, Gonzales, Donaldsonville, Prairieville, 
Denham Springs, Watson, Walker, Pierre Part, Labadieville, 
Paincourtville, Convent, Lutcher, Gramercy, Laplace, Reserve, 
Thibodaux, Raceland, Larose, Destrehan, Norco, Metairie, Kenner, 
Belle Chasse, Chalmette, Violet, Houma, Bayou Cane, Amite, 
Kentwood, Roseland, Wilmer, Hammond, Robert, Ponchatoula, 
Mandeville, Covington, Lacombe, Slidell, New Orleans, 
East New Orleans, Centreville, Dolorosa, Fort Adams, Woodville, 
Gillsberg, Gloster, Smithdale, Liberty, McComb, Dexter, Salem, 
Tylertown, Crossroads, McNeil, Poplarville, Picayune, 
Bay St. Louis, Waveland, Diamondhead, Gulfport, Pascagoula, 
Ocean Springs, Moss Point, Gautier, and St. Martin
1116 AM CDT Sat Jul 31 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...

* WHAT...Dangerously hot conditions with heat index values 110 
  to to 115 expected.

* WHERE...Upper Terrebonne County, and Pointe Coupee, West 
  Feliciana, Iberville, West Baton Rouge, East Baton Rouge, 
  Ascension, Assumption, St. James and Upper Lafourche Parishes.

* WHEN...From 9 AM this morning to 7 PM CDT this evening.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ066>070-010000-
/O.CON.KLIX.HT.Y.0010.000000T0000Z-210801T0000Z/
Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-
Including the cities of Chauvin, Cocodrie, Dulac, Montegut, 
Galliano, Cut Off, Golden Meadow, Leeville, Buras, 
Pointe A La Hache, Port Sulphur, Boothville, Venice, Empire, 
Myrtle Grove, and Yscloskey
1116 AM CDT Sat Jul 31 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...

* WHAT...Heat index values up to 110 expected.

* WHERE...Lower Terrebonne, Lower Lafourche, Lower Jefferson and 
  Lower Plaquemines Parishes.

* WHEN...From 9 AM until 7 PM today.

* IMPACTS...Hot temperatures and high humidity may cause heat 
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$
934 
WWUS74 KLIX 312057
NPWLIX

URGENT - WEATHER MESSAGE
National Weather Service New Orleans LA
357 PM CDT Sat Jul 31 2021

LAZ034>037-039-046>048-050-071-MSZ068>071-077-080>082-010500-
/O.CAN.KLIX.EH.W.0002.000000T0000Z-210801T0000Z/
/O.NEW.KLIX.EH.W.0003.210731T2100Z-210801T0000Z/
/O.NEW.KLIX.HT.Y.0012.210801T1400Z-210802T0000Z/
Pointe Coupee-West Feliciana-East Feliciana-St. Helena-Washington-
Iberville-West Baton Rouge-East Baton Rouge-Livingston-
Northern Tangipahoa-Wilkinson-Amite-Pike-Walthall-Pearl River-
Hancock-Harrison-Jackson-
Including the cities of New Roads, Lettsworth, Livonia, Spillman,
St. Francisville, Wakefield, Jackson, Clinton, Felps, Darlington,
Easleyville, Greensburg, Montpelier, Bogalusa, Enon, Franklinton,
Bayou Sorrel, Plaquemine, White Castle, Port Allen, Addis, 
Brusly, Baton Rouge, Denham Springs, Watson, Walker, Amite, 
Kentwood, Roseland, Wilmer, Centreville, Dolorosa, Fort Adams, 
Woodville, Gillsberg, Gloster, Smithdale, Liberty, McComb, 
Dexter, Salem, Tylertown, Crossroads, McNeil, Poplarville, 
Picayune, Bay St. Louis, Waveland, Diamondhead, Gulfport, 
Pascagoula, Ocean Springs, Moss Point, Gautier, and St. Martin
357 PM CDT Sat Jul 31 2021

...EXCESSIVE HEAT WARNING IN EFFECT UNTIL 7 PM CDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 9 AM TO 7 PM CDT SUNDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot
  conditions with heat index values in excess of 110 degrees. For
  the Heat Advisory, heat index values up to 110 expected.

* WHERE...Portions of southeast and southern Mississippi and 
  southeast Louisiana.

* WHEN...For the Excessive Heat Warning, until 7 PM CDT this 
  evening. For the Heat Advisory, from 9 AM to 7 PM CDT Sunday.

* IMPACTS...Extreme heat and humidity will significantly increase
  the potential for heat related illnesses, particularly for those
  working or participating in outdoor activities.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ049-056>061-063>065-072-075>078-010500-
/O.CAN.KLIX.EH.W.0002.000000T0000Z-210801T0000Z/
/O.NEW.KLIX.HT.Y.0012.210801T1400Z-210802T0000Z/
Ascension-Assumption-St. James-St. John The Baptist-
Upper Lafourche-St. Charles-Upper Jefferson-Upper Plaquemines-
Upper St. Bernard-Upper Terrebonne-Southern Tangipahoa-
Northwest St. Tammany-Southeast St. Tammany-Western Orleans-
Eastern Orleans-
Including the cities of Gonzales, Donaldsonville, Prairieville, 
Pierre Part, Labadieville, Paincourtville, Convent, Lutcher, 
Gramercy, Laplace, Reserve, Thibodaux, Raceland, Larose, 
Destrehan, Norco, Metairie, Kenner, Belle Chasse, Chalmette, 
Violet, Houma, Bayou Cane, Hammond, Robert, Ponchatoula, 
Mandeville, Covington, Lacombe, Slidell, New Orleans, 
and East New Orleans
357 PM CDT Sat Jul 31 2021

...HEAT ADVISORY IN EFFECT FROM 9 AM TO 7 PM CDT SUNDAY...
...EXCESSIVE HEAT WARNING IS CANCELLED...

* WHAT...Heat index values up to 110 expected.

* WHERE...Portions of southeast Louisiana.

* WHEN...From 9 AM to 7 PM CDT Sunday.

* IMPACTS...Hot temperatures and high humidity may cause heat
  illnesses to occur.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Drink plenty of fluids, stay in an air-conditioned room, stay out
of the sun, and check up on relatives and neighbors. Young
children and pets should never be left unattended in vehicles
under any circumstances.

Take extra precautions if you work or spend time outside. When
possible reschedule strenuous activities to early morning or
evening. Know the signs and symptoms of heat exhaustion and heat
stroke. Wear lightweight and loose fitting clothing when
possible. To reduce risk during outdoor work, the Occupational
Safety and Health Administration recommends scheduling frequent
rest breaks in shaded or air conditioned environments. Anyone
overcome by heat should be moved to a cool and shaded location.
Heat stroke is an emergency! Call 9 1 1.

&&

$$

LAZ066>070-312200-
/O.CAN.KLIX.HT.Y.0010.000000T0000Z-210801T0000Z/
Lower Terrebonne-Lower Lafourche-Lower Jefferson-
Lower Plaquemines-Lower St. Bernard-
Including the cities of Chauvin, Cocodrie, Dulac, Montegut, 
Galliano, Cut Off, Golden Meadow, Leeville, Buras, 
Pointe A La Hache, Port Sulphur, Boothville, Venice, Empire, 
Myrtle Grove, and Yscloskey
357 PM CDT Sat Jul 31 2021

...HEAT ADVISORY IS CANCELLED...

Rain cooled air has dropped heat index values below 100 degrees
most places and it is not likely to rebound before sunset.

$$

95/DM

What forecasters said that day

The local office's own words before this excessive heat 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 excessive heat warning went out at Jul 30, 12:40 PM CDT, 3 hours 15 minutes earlier.

Area forecast discussion, Jul 30, 12:40 PM CDT, 3 hours 15 minutes before
Area Forecast Discussion
National Weather Service New Orleans LA
1240 PM CDT Fri Jul 30 2021

.AVIATION...
VFR conditions will prevail through the period with light winds
and generally few to sct low level clouds. Isolated showers and
thunderstorms are expected this afternoon, but the chance of
occurrence within 10 miles of any individual terminal is too low
to mention. The terminals most likely to see shower/thunderstorm
activity are HUM, MSY and NEW, but even probabilities at those
terminals are still 30% or less.

&&

.PREV DISCUSSION... /issued 355 AM CDT Fri Jul 30 2021/

SYNOPSIS...

Upper ridging continues to be centered over Kansas and Oklahoma,
extending southeastward toward Mobile. A weak frontal boundary is
well to the north of the area along Interstate 70. There is the
usual smattering of isolated nocturnal convection over the Gulf
of Mexico, with organized complexes over Missouri, and over the
Gulf well to the south of Pensacola. Temperatures at 3 AM
generally ranged from the mid 70s to lower 80s.

SHORT TERM (through Sunday night)...

Main concern over the next 48 hours or so will be the heat.
Convective threat for today appears to be rather limited, both in
areal coverage and duration. Convection allowing models don't
really show much development prior to about 21z, and the 20-30% we
have in the forecast may even be too high. This is likely to allow
high temperatures in the mid to upper 90s. Only question is
whether drier air mixes down to the surface to lower dew points
somewhat. Heat index values would be somewhat borderline for
Excessive Heat Warnings just on the face of things, but
considering we have been in advisories for about 5 days already,
the cumulative effect of heat stress argues for the higher threat
level. Have expanded the warning to include the Baton Rouge Metro
and areas to the north and west in coordination with the Lake
Charles and Jackson offices today. Have also opted to place the
lower portions of the Louisiana coastal parishes in the Heat
Advisory.

For Saturday, the heat will continue to be a problem, but won't
make any adjustments to advisories or watches for now until we see
how today plays out. Somewhat of a challenging forecast
convectively on Saturday, as the GFS solution carries considerably
more convection than the remaining solutions. GFS is considerably
further south than the remaining solutions. Moisture levels will
be higher tomorrow than today as noted by higher precipitable
water levels on forecast soundings. The GFS solution with it's
higher precipitation chances would not support heat
advisories/warnings, but the NAM/ECMWF/NBM solutions with their
lower chances would. Will trend below GFS PoP solution, thus
higher temperatures.

A little better rain chances on Sunday as upper troughing and
surface boundary move closer to the area. Should be enough to back
the temperatures down a couple degrees.

LONG TERM (Monday and beyond)...

A rather deep mid/upper longwave trough for early August will
amplify down into the southeast U.S. and northeast Gulf coast during
the early to middle of the upcoming week. This will send a weak cold
front down into the forecast area. This frontal boundary will likely
move slowly towards and into the area on Monday into Tuesday, so
that is likely to be two wetter days with high rain chances and
potential for locally heavy rainfall. The front may move far enough
south into coastal areas to actually bring drier conditions over at
least northern areas Tuesday night into Wednesday and possibly
Thursday as well, however the NBM guidance does not completely lower
the rain chances as aggressively as the operational runs of the
models. Have stayed very close to the NBM as it appears to be
factoring what is likely a bias of the operational runs showing too
much integrity to an early August front with regards to the lowering
of lower temperatures.

MARINE...

Main concern will remain the threat of convection through the
forecast period. Outside of convection, wind/wave conditions are
not expected to produce significant issues.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  96  77  96  76 /  20  10  30  10
BTR  96  78  95  77 /  20  10  40  10
ASD  96  79  97  79 /  20  10  40  20
MSY  97  83  97  82 /  30  10  50  20
GPT  96  80  95  79 /  20  10  40  20
PQL  97  79  97  79 /  20  10  40  20

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory until 7 PM CDT this evening for LAZ066>069.

     Excessive Heat Warning until 7 PM CDT this evening for
     LAZ034>037-039-046>050-056>061-063>065-070>072-075>078.

     Excessive Heat Watch from Saturday morning through Saturday
     evening for LAZ037-039-049-050-056>061-063>065-070>072-
     075>078.

     Heat Advisory from 9 AM to 7 PM CDT Saturday for LAZ034>036-
     046>048.

GM...None.
MS...Excessive Heat Warning until 7 PM CDT this evening for
     MSZ068>071-077-080>082.

     Excessive Heat Watch from Saturday morning through Saturday
     evening for MSZ070-071-077-080>082.

     Heat Advisory from 9 AM to 7 PM CDT Saturday for MSZ068-069.

GM...None.
&&

Aviation...95/DM
Prev short/marine...22/TD
Prev long...35

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 3:59 AM CDTHeat AdvisoryLIX15 hr

Nearby

Excessive Heat Warnings in Louisiana, 2021Excessive Heat Warnings in Mississippi, 2021Every excessive heat warning 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.