Alert archive / Mississippi / Heat Advisories in 2021

Heat Advisory 11, NWS Jackson, MS

August 24, 202134 counties in Mississippi; 9 parishes in Louisiana; Ashley County, Chicot County, Arkansas

NWS Jackson, MS issued this heat advisory at Aug 24, 2021, 3:01 PM CDT for 34 counties in Mississippi; 9 parishes in Louisiana; Ashley County, Chicot County, Arkansas. It took effect at Aug 25, 2021, 10:00 AM CDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Aug 24, 2021, 3:01 PM CDT (20:01 UTC)
In effect from
Aug 25, 2021, 10:00 AM CDT
Expired
Aug 25, 2021, 7:00 PM CDT
In force
9 hr
Issued by
NWS Jackson, MS
All 45 counties

Ashley County, AR, Chicot County, AR, Catahoula Parish, LA, Concordia Parish, LA, East Carroll Parish, LA, Franklin Parish, LA, Madison Parish, LA, Morehouse Parish, LA, Richland Parish, LA, Tensas Parish, LA, West Carroll Parish, LA, Adams County, MS, Attala County, MS, Bolivar County, MS, Carroll County, MS, Claiborne County, MS, Copiah County, MS, Covington County, MS, Forrest County, MS, Franklin County, MS, Grenada County, MS, Hinds County, MS, Holmes County, MS, Humphreys County, MS, Issaquena County, MS, Jefferson County, MS, Jefferson Davis County, MS, Jones County, MS, Lamar County, MS, Lawrence County, MS, Leake County, MS, Leflore County, MS, Lincoln County, MS, Madison County, MS, Marion County, MS, Montgomery County, MS, Rankin County, MS, Scott County, MS, Sharkey County, MS, Simpson County, MS, Smith County, MS, Sunflower County, MS, Warren County, MS, Washington County, MS, Yazoo County, MS

The radar

The Jackson/Brandon,MS radar (KDGX), 53 km from the middle of the area, began a volume at 20:05 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Jackson, MS (KJAN), launched 12:00Z, 8.0 hours before the alert went out and 43 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 2021-08-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 751 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 2021-08-24The 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
751 J/kg
Mixed-layer CIN
-70 J/kg
Mixed-layer LCL
1224 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
15 m²/s²
0-3 km storm-relative helicity
61 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

107 
WWUS74 KJAN 242001
NPWJAN

URGENT - WEATHER MESSAGE
National Weather Service Jackson MS
301 PM CDT Tue Aug 24 2021

ARZ074-075-LAZ007>009-015-016-023-025-MSZ018-019-025-034-035-
040>042-047-048-053-054-059-061>063-250415-
/O.NEW.KJAN.HT.Y.0011.210825T1500Z-210826T0000Z/
/O.CON.KJAN.EH.W.0002.000000T0000Z-210825T0000Z/
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Tensas-Bolivar-Sunflower-Leflore-
Washington-Humphreys-Issaquena-Sharkey-Yazoo-Warren-Hinds-
Claiborne-Copiah-Jefferson-Franklin MS-Lincoln-Lawrence-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Bastrop, Oak Grove,
Epps, Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, 
Newellton, St. Joseph, Waterproof, Cleveland, Indianola, 
Ruleville, Greenwood, Greenville, Belzoni, Isola, Mayersville, 
Rolling Fork, Anguilla, Yazoo City, Vicksburg, Jackson, 
Port Gibson, Crystal Springs, Hazlehurst, Wesson, Fayette, Bude, 
Roxie, Meadville, Brookhaven, Monticello, and New Hebron
301 PM CDT Tue Aug 24 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...HEAT ADVISORY IN EFFECT FROM 10 AM TO 7 PM CDT WEDNESDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot
  conditions with heat index values up to 115. For the Heat
  Advisory, heat index values up to 110 expected.

* WHERE...Portions of northeast Louisiana, central, north 
  central, northwest, south central, southwest and west central 
  Mississippi and southeast Arkansas.

* WHEN...For the Excessive Heat Warning, until 7 PM CDT this 
  evening. For the Heat Advisory, from 10 AM to 7 PM CDT 
  Wednesday.

* 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.

&&

$$

LAZ024-026-MSZ060-250415-
/O.NEW.KJAN.HT.Y.0011.210825T1500Z-210826T0000Z/
/O.CON.KJAN.EH.W.0003.000000T0000Z-210825T0000Z/
Catahoula-Concordia-Adams-
Including the cities of Jonesville, Harrisonburg, Vidalia, 
Ferriday, West Ferriday, and Natchez
301 PM CDT Tue Aug 24 2021

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 7 PM CDT THIS
EVENING...
...HEAT ADVISORY IN EFFECT FROM 10 AM TO 7 PM CDT WEDNESDAY...

* WHAT...For the Excessive Heat Warning, dangerously hot
  conditions with heat index values up to 115. For the Heat
  Advisory, heat index values up to 110 expected.

* WHERE...In Mississippi, Adams County. In Louisiana, Catahoula 
  and Concordia Counties.

* WHEN...For the Excessive Heat Warning, until 7 PM CDT this 
  evening. For the Heat Advisory, from 10 AM to 7 PM CDT 
  Wednesday.

* 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.

&&

$$

MSZ026>028-036-037-043-044-049-050-055-056-064>066-072>074-250415-
/O.NEW.KJAN.HT.Y.0011.210825T1500Z-210826T0000Z/
/O.CON.KJAN.HT.Y.0010.000000T0000Z-210825T0000Z/
Grenada-Carroll-Montgomery-Holmes-Attala-Madison MS-Leake-Rankin-
Scott-Simpson-Smith-Jefferson Davis-Covington-Jones-Marion-Lamar-
Forrest-
Including the cities of Grenada, Vaiden, North Carrollton, 
Carrollton, Winona, Durant, Tchula, Lexington, Pickens, Goodman, 
Kosciusko, Ridgeland, Madison, Canton, Carthage, Pearl, Brandon, 
Richland, Forest, Morton, Magee, Mendenhall, Taylorsville, 
Raleigh, Prentiss, Bassfield, Collins, Mount Olive, Laurel, 
Columbia, West Hattiesburg, Lumberton, Purvis, and Hattiesburg
301 PM CDT Tue Aug 24 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 10 AM TO 7 PM CDT WEDNESDAY...

* WHAT...For the Heat Advisory, heat index values up to 110. 

* WHERE...Portions of central, north central, south central and 
  southeast Mississippi.

* WHEN...For the first Heat Advisory, until 7 PM CDT this 
  evening. For the second Heat Advisory, from 10 AM to 7 PM CDT 
  Wednesday.

* 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.

&&

$$
4 follow-up statements
595 
WWUS74 KJAN 250205
NPWJAN

URGENT - WEATHER MESSAGE
National Weather Service Jackson MS
905 PM CDT Tue Aug 24 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>028-034>037-
040>044-047>050-053>056-059>066-072>074-251015-
/O.CON.KJAN.HT.Y.0011.210825T1500Z-210826T0000Z/
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Montgomery-Washington-Humphreys-
Holmes-Attala-Issaquena-Sharkey-Yazoo-Madison MS-Leake-Warren-
Hinds-Rankin-Scott-Claiborne-Copiah-Simpson-Smith-Jefferson-Adams-
Franklin MS-Lincoln-Lawrence-Jefferson Davis-Covington-Jones-
Marion-Lamar-Forrest-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Bastrop, Oak Grove,
Epps, Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, 
Jonesville, Harrisonburg, Newellton, St. Joseph, Waterproof, 
Vidalia, Ferriday, West Ferriday, Cleveland, Indianola, 
Ruleville, Greenwood, Grenada, Vaiden, North Carrollton, 
Carrollton, Winona, Greenville, Belzoni, Isola, Durant, Tchula, 
Lexington, Pickens, Goodman, Kosciusko, Mayersville, 
Rolling Fork, Anguilla, Yazoo City, Ridgeland, Madison, Canton, 
Carthage, Vicksburg, Jackson, Pearl, Brandon, Richland, Forest, 
Morton, Port Gibson, Crystal Springs, Hazlehurst, Wesson, Magee, 
Mendenhall, Taylorsville, Raleigh, Fayette, Natchez, Bude, Roxie,
Meadville, Brookhaven, Monticello, New Hebron, Prentiss, 
Bassfield, Collins, Mount Olive, Laurel, Columbia, 
West Hattiesburg, Lumberton, Purvis, and Hattiesburg
905 PM CDT Tue Aug 24 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 10 AM TO 7 PM CDT
WEDNESDAY...

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

* WHERE...Portions of northeast Louisiana, southeast Arkansas and
  much of central Mississippi.

* WHEN...10 AM to 7 PM CDT Wednesday.

* 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.

&&

$$
609 
WWUS74 KJAN 250704 AAA
NPWJAN

URGENT - WEATHER MESSAGE...UPDATED
National Weather Service Jackson MS
204 AM CDT Wed Aug 25 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>028-034>037-
040>044-047>050-053>056-059>066-072>074-251515-
/O.CON.KJAN.HT.Y.0011.210825T1500Z-210826T0000Z/
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Montgomery-Washington-Humphreys-
Holmes-Attala-Issaquena-Sharkey-Yazoo-Madison MS-Leake-Warren-
Hinds-Rankin-Scott-Claiborne-Copiah-Simpson-Smith-Jefferson-Adams-
Franklin MS-Lincoln-Lawrence-Jefferson Davis-Covington-Jones-
Marion-Lamar-Forrest-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Bastrop, Oak Grove,
Epps, Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, 
Jonesville, Harrisonburg, Newellton, St. Joseph, Waterproof, 
Vidalia, Ferriday, West Ferriday, Cleveland, Indianola, 
Ruleville, Greenwood, Grenada, Vaiden, North Carrollton, 
Carrollton, Winona, Greenville, Belzoni, Isola, Durant, Tchula, 
Lexington, Pickens, Goodman, Kosciusko, Mayersville, 
Rolling Fork, Anguilla, Yazoo City, Ridgeland, Madison, Canton, 
Carthage, Vicksburg, Jackson, Pearl, Brandon, Richland, Forest, 
Morton, Port Gibson, Crystal Springs, Hazlehurst, Wesson, Magee, 
Mendenhall, Taylorsville, Raleigh, Fayette, Natchez, Bude, Roxie,
Meadville, Brookhaven, Monticello, New Hebron, Prentiss, 
Bassfield, Collins, Mount Olive, Laurel, Columbia, 
West Hattiesburg, Lumberton, Purvis, and Hattiesburg
204 AM CDT Wed Aug 25 2021

...HEAT ADVISORY REMAINS IN EFFECT FROM 10 AM THIS MORNING TO
7 PM CDT THIS EVENING...

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

* WHERE...Portions of northeast Louisiana, southeast Arkansas 
  and much of central Mississippi.

* WHEN...10 AM to 7 PM CDT Wednesday.

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

&&

$$

DC
205 
WWUS74 KJAN 251500
NPWJAN

URGENT - WEATHER MESSAGE
National Weather Service Jackson MS
1000 AM CDT Wed Aug 25 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>028-034>037-
040>044-047>050-053>056-059>066-072>074-252300-
/O.CON.KJAN.HT.Y.0011.000000T0000Z-210826T0000Z/
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Montgomery-Washington-Humphreys-
Holmes-Attala-Issaquena-Sharkey-Yazoo-Madison MS-Leake-Warren-
Hinds-Rankin-Scott-Claiborne-Copiah-Simpson-Smith-Jefferson-Adams-
Franklin MS-Lincoln-Lawrence-Jefferson Davis-Covington-Jones-
Marion-Lamar-Forrest-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Bastrop, Oak Grove,
Epps, Lake Providence, Rayville, Delhi, Tallulah, Winnsboro, 
Jonesville, Harrisonburg, Newellton, St. Joseph, Waterproof, 
Vidalia, Ferriday, West Ferriday, Cleveland, Indianola, 
Ruleville, Greenwood, Grenada, Vaiden, North Carrollton, 
Carrollton, Winona, Greenville, Belzoni, Isola, Durant, Tchula, 
Lexington, Pickens, Goodman, Kosciusko, Mayersville, 
Rolling Fork, Anguilla, Yazoo City, Ridgeland, Madison, Canton, 
Carthage, Vicksburg, Jackson, Pearl, Brandon, Richland, Forest, 
Morton, Port Gibson, Crystal Springs, Hazlehurst, Wesson, Magee, 
Mendenhall, Taylorsville, Raleigh, Fayette, Natchez, Bude, Roxie,
Meadville, Brookhaven, Monticello, New Hebron, Prentiss, 
Bassfield, Collins, Mount Olive, Laurel, Columbia, 
West Hattiesburg, Lumberton, Purvis, and Hattiesburg
1000 AM CDT Wed Aug 25 2021

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

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

* WHERE...Portions of northeast Louisiana, southeast Arkansas 
  and much of central Mississippi.

* WHEN...10 AM to 7 PM CDT Wednesday.

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

&&

$$

AJ
511 
WWUS74 KJAN 252010
NPWJAN

URGENT - WEATHER MESSAGE
National Weather Service Jackson MS
310 PM CDT Wed Aug 25 2021

ARZ074-075-LAZ007>009-015-016-MSZ018-019-025>027-034>036-040>043-
047-048-260415-
/O.NEW.KJAN.HT.Y.0012.210826T1500Z-210827T0000Z/
/O.CON.KJAN.HT.Y.0011.000000T0000Z-210826T0000Z/
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Bolivar-Sunflower-Leflore-Grenada-Carroll-Washington-
Humphreys-Holmes-Issaquena-Sharkey-Yazoo-Madison MS-Warren-Hinds-
Including the cities of Crossett, North Crossett, Hamburg, 
West Crossett, Dermott, Lake Village, Eudora, Bastrop, Oak Grove,
Epps, Lake Providence, Rayville, Delhi, Tallulah, Cleveland, 
Indianola, Ruleville, Greenwood, Grenada, Vaiden, 
North Carrollton, Carrollton, Greenville, Belzoni, Isola, Durant,
Tchula, Lexington, Pickens, Goodman, Mayersville, Rolling Fork, 
Anguilla, Yazoo City, Ridgeland, Madison, Canton, Vicksburg, 
and Jackson
310 PM CDT Wed Aug 25 2021

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM CDT THIS EVENING...
...HEAT ADVISORY IN EFFECT FROM 10 AM TO 7 PM CDT THURSDAY...

* WHAT...Heat index values between 105 and 110 degrees expected.

* WHERE...Portions of northeast Louisiana, central, north 
  central, northwest and west central Mississippi and southeast 
  Arkansas.

* WHEN...For the first Heat Advisory, until 7 PM CDT this 
  evening. For the second Heat Advisory, from 10 AM to 7 PM CDT 
  Thursday.

* 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.

&&

$$

LAZ023>026-MSZ028-037-044-049-050-053>056-059>066-072>074-260000-
/O.CON.KJAN.HT.Y.0011.000000T0000Z-210826T0000Z/
Franklin LA-Catahoula-Tensas-Concordia-Montgomery-Attala-Leake-
Rankin-Scott-Claiborne-Copiah-Simpson-Smith-Jefferson-Adams-
Franklin MS-Lincoln-Lawrence-Jefferson Davis-Covington-Jones-
Marion-Lamar-Forrest-
Including the cities of Winnsboro, Jonesville, Harrisonburg, 
Newellton, St. Joseph, Waterproof, Vidalia, Ferriday, 
West Ferriday, Winona, Kosciusko, Carthage, Pearl, Brandon, 
Richland, Forest, Morton, Port Gibson, Crystal Springs, 
Hazlehurst, Wesson, Magee, Mendenhall, Taylorsville, Raleigh, 
Fayette, Natchez, Bude, Roxie, Meadville, Brookhaven, Monticello,
New Hebron, Prentiss, Bassfield, Collins, Mount Olive, Laurel, 
Columbia, West Hattiesburg, Lumberton, Purvis, and Hattiesburg
310 PM CDT Wed Aug 25 2021

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

* WHAT...Heat index values between 105 and 110 degrees expected.

* WHERE...Portions of northeast Louisiana, southeast Arkansas 
  and much of central Mississippi.

* WHEN...until 7 PM CDT Today.

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

&&

$$

AJ

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 Jackson, MS wrote its last area forecast discussion before this heat advisory went out at Aug 24, 12:12 PM CDT, 2 hours 49 minutes earlier.

Area forecast discussion, Aug 24, 12:12 PM CDT, 2 hours 49 minutes before
Area Forecast Discussion
National Weather Service Jackson MS
1212 PM CDT Tue Aug 24 2021

.UPDATE...
Updated for 18Z aviation discussion

&&

.AVIATION...
18Z TAF discussion:
Expect VFR and light winds for most of the period. VCTS will be
possible for the southeast this afternoon and evening where better
chances for convection will exist. MVFR vis will be possible late
tonight for KGTR/KHBG/KPIB. /27/

&&

.DISCUSSION...
Hot and humid conditions will continue today as highs reach the mid
90s east to near 100 west. Heat index values will range from around
100 east to near 115 in the west. An Excessive Heat Warning remains
in effect for portions of the west and central, with a Heat Advisory
in effect for portions of the central and east. Isolated showers and
storms will be possible this afternoon and evening across much of
the area. No major changes were needed to the current forecast. /27/

Prior discussion below:

Today & tonight...

Dangerous heat stress is expected today with some chances for
iso-sct aftn rain & storms across the S.

Tues: Expansive mid-level ridge axis is centered over the S Plains &
E-NE flow aloft in the ArkLaMiss. 00Z upper air analysis & GOES E
imagery this morning indicate drier air over N central AL is
advecting to the SW & will gradually move into the area. PWs in GOES
E obs & 00Z BMX sounding indicate less than an inch & a half PWs.
This drier air is progged to advect SW, which will keep rain & iso-
sct storm chances somewhat suppressed to the S & W, generally along
the MS River & along & S of I-20 corridor. With anomalous low-level
thermal warmth, persistence for highs could get in mid-upper 90s &
heat indices similar to Mon. "Significant"/dangerous heat stress
will continue for areas generally along & W of I-55 corridor. Due to
that, kept the ongoing Excessive Heat Warning & exterior Heat
Advisory configuration & timing the same. Some drier low-level air
could help dewpoints mix out a little better to the E & keep heat
stress potential more spotty. Stay cool, hydrated & take all of your
heat safety precautions.

Tonight: Synoptic & sfc pattern will persist, with a retrograding
upper low moving into the Bahamas, while persistent ridge axis will
remain to the W-NW. With increased low-level moisture, lows will
remain above normal in the low-mid 70s. Deeper moisture & mass
convergence will move in late in the SE & a rogue shower or so can't
be ruled out. However, potential will increase more into the aftn
Wed. /DC/

Tomorrow through Tuesday:

The forecast period starts off tomorrow with stout upper ridging
retrograding into the Central Plains to the south of active
westerlies draped along the International Border. Heights will
finally begin to lower across the area which will bring a gradual
end to the oppressive heat conditions. One more day of heat
advisories is likely on Wednesday with heat index values ranging
from 105-110 degrees, especially across the Delta. The ongoing
elevated and limited areas in the HWO/graphics will also be
continued as is. Isolated to scattered coverage of showers and
thunderstorms will also slowly return on Wednesday with the greatest
chances confined to the Pine Belt as seabreeze convection and their
respective boundaries penetrate inland.

Heading into Thursday through the weekend, global guidance continues
to peg the arrival of a Tropical Upper Tropospheric Trough (TUTT)
and associated closed low. This feature is forecast to cross the
Florida peninsula on Thursday morning and into the Lower Mississippi
Valley by the weekend. At the same time, stout sub-tropical ridging
originating from Bermuda will slide west into the coastal plain of
the Carolinas. Resulting southeasterly flow on the western periphery
of the ridge will bring several bouts of deep tropical moisture into
the area. This moisture, in conjunction with the TUTT, will yield
scattered to numerous showers and thunderstorms each day. Friday may
see slightly reduced coverage as a PWAT minimum traverses the area,
but at least scattered coverage is still likely. Low heights and
increasing cloud cover and rain chances will keep temperatures in
check. Afternoon highs will range from the upper 80s to low 90s,
with heat indices remaining below advisory criteria.

By early next week, the synoptic pattern will remain generally
unchanged with a persistent warm and moist late summer pattern
continuing. However, attention will quickly shift to the tropics as
a wave emerges from the Tropical Atlantic into the Caribbean. The
National Hurricane Center gives this activity a 60% chance of
development as it moves into the Northwest Caribbean. Overnight
global model guidance and their respective ensembles are in
agreement with a tropical cyclone tracking across the Yucatan
Peninsula and into the Bay of Campeche by Sunday morning. Ensemble
track envelopes expand significantly beyond this point in time,
which coincides with the flattening of the Carolinas ridge as a
potent northern stream shortwave trough slides through the Northern
Plains and into the Great Lakes region. Ultimately, the track of any
tropical cyclone will depend on strength and placement of the ridge,
thus forecast confidence remains low at this time. /TW/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       96  75  95  74 /  16   4  43   8
Meridian      95  74  94  72 /  14   2  49  10
Vicksburg    100  77  97  75 /  16   4  27   5
Hattiesburg   96  75  92  73 /  30   8  62  19
Natchez       96  75  95  74 /  27   8  45   8
Greenville    98  75  96  74 /  13   2  13   2
Greenwood     97  74  97  74 /   8   2  15   3

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 7 PM CDT this evening for MSZ026>028-036-037-
     043-044-049-050-055-056-064>066-072>074.

     Excessive Heat Warning until 7 PM CDT this evening for MSZ018-
     019-025-034-035-040>042-047-048-053-054-059>063.

LA...Excessive Heat Warning until 7 PM CDT this evening for
     LAZ007>009-015-016-023>026.

AR...Excessive Heat Warning until 7 PM CDT this evening for ARZ074-
     075.

&&
Hazardous weather outlook, Aug 24, 2:48 PM CDT, 13 minutes before
Hazardous Weather Outlook
National Weather Service Jackson MS
248 PM CDT Tue Aug 24 2021

ARZ074-075-LAZ007>009-015-016-023>026-MSZ018-019-025>027-034>036-
040>043-047-048-053>055-059>064-072-252000-
Ashley-Chicot-Morehouse-West Carroll-East Carroll-Richland-
Madison LA-Franklin LA-Catahoula-Tensas-Concordia-Bolivar-
Sunflower-Leflore-Grenada-Carroll-Washington-Humphreys-Holmes-
Issaquena-Sharkey-Yazoo-Madison MS-Warren-Hinds-Claiborne-Copiah-
Simpson-Jefferson-Adams-Franklin MS-Lincoln-Lawrence-
Jefferson Davis-Marion-
248 PM CDT Tue Aug 24 2021

This hazardous weather outlook is for portions of southeast
Arkansas, northeast Louisiana, central Mississippi, north central
Mississippi, northwest Mississippi, south central Mississippi,
southwest Mississippi, and west central Mississippi.

.DAY ONE...Tonight and Wednesday

DANGEROUS HEAT
THREAT...Elevated
TIMING...Wednesday

Wednesday, dangerous heat likely with peak heat index values
ranging from 106 to 110 degrees. Heat exhaustion will be likely
with outdoor activity.

(https://www.weather.gov/images/jan/graphicast/2.png)

.DAYS TWO THROUGH SEVEN...Wednesday night through Monday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations is not expected through next Monday.

MSZ028>033-037>039-044>046-049>052-056>058-065-066-073-074-252000-
Montgomery-Webster-Clay-Lowndes-Choctaw-Oktibbeha-Attala-Winston-
Noxubee-Leake-Neshoba-Kemper-Rankin-Scott-Newton-Lauderdale-Smith-
Jasper-Clarke-Covington-Jones-Lamar-Forrest-
248 PM CDT Tue Aug 24 2021

This hazardous weather outlook is for portions of central
Mississippi, east central Mississippi, north central Mississippi,
northeast Mississippi, and southeast Mississippi.

.DAY ONE...Tonight and Wednesday

DANGEROUS HEAT
THREAT...Limited
TIMING...Wednesday

Wednesday, caution is advised for possible dangerous heat as heat
index values peak near 105 degrees. Heat exhaustion will be
possible with outdoor activity.

(https://www.weather.gov/images/jan/graphicast/2.png)

.DAYS TWO THROUGH SEVEN...Wednesday night through Monday

The probability for widespread hazardous weather is low.

.SPOTTER CALL TO ACTION STATEMENT...
The activation of storm spotters, HAM radio operators, and
emergency management personnel in support of severe weather
operations is not expected through next Monday.

27

&&

...HAZARD LEGEND...

*DANGEROUS HEAT*
Extreme...Extreme heat is expected with peak heat index values
 in excess of 110 degrees for multiple days. Heat stroke continues
 to be a major concern.
Significant...Dangerous heat expected with peak heat index values
 in excess of 110 degrees. Heat stroke will be a significant
 concern.
Elevated...Dangerous heat likely with peak heat index values
 ranging from 106 to 110 degrees. Heat exhaustion will be likely.
Limited...Caution is advised for possible dangerous heat as
 heat index values peak near 105 degrees. Heat exhaustion will
 be possible.

...USEFUL WEATHER WEB PAGES (URLS)...

NWS JAN Home page...
   https://www.weather.gov/jan
Stay Aware, Stay Safe NWS JAN Briefing Page...
   https://www.weather.gov/jan/safe
Latest Weather Briefing...
   https://www.weather.gov/jan/weather_briefing

Tropical page...
   https://www.weather.gov/srh/tropical?office=jan
National Hurricane Center Home Page...
   https://www.nhc.noaa.gov/
Find NWS JAN on Facebook...
   https://www.facebook.com/NWSJacksonMS
Follow NWS JAN on Twitter...
   @NWSJacksonMS
Follow NWS JAN on Youtube...
   https://www.youtube.com/user/NWSJacksonMiss

The office that day

Everything else NWS Jackson, MS issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 24, 5:06 PM CDTSpecial Weather StatementJANFranklin24 min

Nearby

Heat Advisories in Mississippi, 2021Heat Advisories in Louisiana, 2021Heat Advisories in Arkansas, 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; radar from the NEXRAD Level II archive.