Alert archive / Louisiana / Flash Flood Watches in 2021

Flash Flood Watch 4, NWS New Orleans, LA

May 1, 202115 parishes in Louisiana; 5 counties in Mississippi

NWS New Orleans, LA issued this flash flood watch at May 1, 2021, 2:46 PM CDT for 15 parishes in Louisiana; 5 counties in Mississippi. It took effect at May 2, 2021, 1:00 AM CDT. It was in force for 14 hr.

The area

The counties it named.

The facts

Issued
May 1, 2021, 2:46 PM CDT (19:46 UTC)
In effect from
May 2, 2021, 1:00 AM CDT
Expired
May 2, 2021, 3:00 PM CDT
In force
14 hr
Issued by
NWS New Orleans, LA
Flood severity
None

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, 7.8 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 12:00Z on 2021-05-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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 2021-05-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1869 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
99 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

080 
WGUS64 KLIX 011946
FFALIX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New Orleans LA
246 PM CDT Sat May 1 2021

LAZ034>037-039-046>050-056>058-071-072-075-076-MSZ068>071-077-
080>082-020400-
/O.NEW.KLIX.FF.A.0004.210502T0600Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
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-Northern Tangipahoa-
Southern Tangipahoa-Northwest St. Tammany-Southeast St. Tammany-
Wilkinson-Amite-Pike-Walthall-Pearl River-Hancock-Harrison-Jackson-
Including the cities of Gillsberg, Dolorosa, Donaldsonville, 
Hammond, Jackson, Spillman, Gonzales, Robert, Bogalusa, Dexter, 
Liberty, Denham Springs, Lacombe, Covington, Port Allen, 
Poplarville, Tylertown, Lutcher, Plaquemine, Centreville, Watson, 
Pascagoula, Fort Adams, Brusly, Bayou Sorrel, Roseland, Gramercy, 
Amite, Baton Rouge, Lettsworth, Pierre Part, New Roads, Salem, 
Franklinton, Addis, Paincourtville, Reserve, Ponchatoula, Kentwood, 
Moss Point, St. Francisville, Greensburg, Felps, Wakefield, Enon, 
Gloster, Slidell, Picayune, Diamondhead, Easleyville, Gautier, 
Gulfport, Ocean Springs, Walker, Woodville, Crossroads, 
Labadieville, Laplace, White Castle, Bay St. Louis, Clinton, McComb, 
Mandeville, Convent, Prairieville, Montpelier, Waveland, Livonia, 
Darlington, St. Martin, Wilmer, Smithdale, and McNeil
246 PM CDT Sat May 1 2021

...FLASH FLOOD WATCH IN EFFECT FROM LATE TONIGHT THROUGH LATE SUNDAY 
NIGHT...

The National Weather Service in New Orleans has issued a

* Flash Flood Watch for portions of southeast Louisiana and 
  Mississippi, including the following areas, in southeast 
  Louisiana, Ascension, Assumption, East Baton Rouge, East 
  Feliciana, Iberville, Livingston, Northern Tangipahoa, Northwest 
  St. Tammany, Pointe Coupee, Southeast St. Tammany, Southern 
  Tangipahoa, St. Helena, St. James, St. John The Baptist, 
  Washington, West Baton Rouge and West Feliciana. In Mississippi, 
  Amite, Hancock, Harrison, Jackson, Pearl River, Pike, Walthall and 
  Wilkinson.

* From 1 AM CDT Sunday through late Sunday night

* Rainfall totals of 1 to 3 inches with locally higher amounts are 
  forecast late tonight through Sunday night.

* High rainfall rates could overwhelm drainage capacity. Ponding of 
  water in low lying and poor drainage areas can be expected, with 
  flash flooding possible where the heaviest rain falls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

Be sure to have multiple ways to receive flash flood warnings should 
they become necessary for your area. And remember, never drive 
through flooded roadways as the water may be too deep for safe 
passage.

&&

$$

DM
4 follow-up statements
489 
WGUS64 KLIX 020130
FFALIX

Flood Watch
National Weather Service New Orleans LA
830 PM CDT Sat May 1 2021

LAZ034>037-039-046>050-056>058-071-072-075-076-MSZ068>071-077-
080>082-021030-
/O.CON.KLIX.FF.A.0004.210502T0600Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
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-Northern Tangipahoa-
Southern Tangipahoa-Northwest St. Tammany-Southeast St. Tammany-
Wilkinson-Amite-Pike-Walthall-Pearl River-Hancock-Harrison-Jackson-
Including the cities of Gillsberg, Dolorosa, Donaldsonville, 
Hammond, Jackson, Spillman, Gonzales, Robert, Bogalusa, Dexter, 
Liberty, Denham Springs, Lacombe, Covington, Port Allen, 
Poplarville, Tylertown, Lutcher, Plaquemine, Centreville, Watson, 
Pascagoula, Fort Adams, Brusly, Bayou Sorrel, Roseland, Gramercy, 
Amite, Baton Rouge, Lettsworth, Pierre Part, New Roads, Salem, 
Franklinton, Addis, Paincourtville, Reserve, Ponchatoula, Kentwood, 
Moss Point, St. Francisville, Greensburg, Felps, Wakefield, Enon, 
Gloster, Slidell, Picayune, Diamondhead, Easleyville, Gautier, 
Gulfport, Ocean Springs, Walker, Woodville, Crossroads, 
Labadieville, Laplace, White Castle, Bay St. Louis, Clinton, McComb, 
Mandeville, Convent, Prairieville, Montpelier, Waveland, Livonia, 
Darlington, St. Martin, Wilmer, Smithdale, and McNeil
830 PM CDT Sat May 1 2021

...FLASH FLOOD WATCH IN EFFECT FROM LATE TONIGHT THROUGH LATE SUNDAY 
NIGHT...

The Flash Flood Watch continues for

* Portions of southeast Louisiana and Mississippi, including the 
  following areas, in southeast Louisiana, Ascension, Assumption, 
  East Baton Rouge, East Feliciana, Iberville, Livingston, Northern 
  Tangipahoa, Northwest St. Tammany, Pointe Coupee, Southeast St. 
  Tammany, Southern Tangipahoa, St. Helena, St. James, St. John The 
  Baptist, Washington, West Baton Rouge and West Feliciana. In 
  Mississippi, Amite, Hancock, Harrison, Jackson, Pearl River, Pike, 
  Walthall and Wilkinson.

* From 1 AM CDT Sunday through late Sunday night

* Rainfall totals of 1 to 3 inches with locally higher amounts are 
  forecast late tonight through Sunday night.

* High rainfall rates could overwhelm drainage capacity. Ponding of 
  water in low lying and poor drainage areas can be expected, with 
  flash flooding possible where the heaviest rain falls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

Be sure to have multiple ways to receive flash flood warnings should 
they become necessary for your area. And remember, never drive 
through flooded roadways as the water may be too deep for safe 
passage.

&&

$$

PG
162 
WGUS64 KLIX 020829
FFALIX

Flood Watch
National Weather Service New Orleans LA
329 AM CDT Sun May 2 2021

LAZ059>061-063>070-077-078-022030-
/O.EXA.KLIX.FF.A.0004.000000T0000Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Upper Lafourche-St. Charles-Upper Jefferson-Upper Plaquemines-Upper
St. Bernard-Upper Terrebonne-Lower Terrebonne-Lower Lafourche-Lower
Jefferson-Lower Plaquemines-Lower St. Bernard-Western Orleans-
Eastern Orleans-
Including the cities of Cocodrie, Venice, Chalmette, Larose, 
Galliano, Buras, Golden Meadow, Cut Off, Belle Chasse, Destrehan, 
East New Orleans, Bayou Cane, Metairie, Houma, Thibodaux, 
Boothville, Leeville, Kenner, Chauvin, Raceland, Norco, Empire, 
Pointe A La Hache, Port Sulphur, Yscloskey, Myrtle Grove, New 
Orleans, Montegut, Violet, and Dulac
329 AM CDT Sun May 2 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH LATE TONIGHT...

The National Weather Service in New Orleans has expanded the

* Flash Flood Watch to include a portion of southeast Louisiana, 
  including the following areas, Eastern Orleans, Lower Jefferson, 
  Lower Lafourche, Lower Plaquemines, Lower St. Bernard, Lower 
  Terrebonne, St. Charles, Upper Jefferson, Upper Lafourche, Upper 
  Plaquemines, Upper St. Bernard, Upper Terrebonne and Western 
  Orleans.

* Through late tonight

* Rainfall totals of 1 to 3 inches with locally higher amounts are 
  forecast through tonight.

$$

LAZ034>037-039-046>050-056>058-071-072-075-076-MSZ068>071-077-
080>082-022030-
/O.CON.KLIX.FF.A.0004.000000T0000Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
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-Northern Tangipahoa-
Southern Tangipahoa-Northwest St. Tammany-Southeast St. Tammany-
Wilkinson-Amite-Pike-Walthall-Pearl River-Hancock-Harrison-Jackson-
Including the cities of Gillsberg, Dolorosa, Donaldsonville, 
Hammond, Jackson, Spillman, Gonzales, Robert, Bogalusa, Dexter, 
Liberty, Denham Springs, Lacombe, Covington, Port Allen, 
Poplarville, Tylertown, Lutcher, Plaquemine, Centreville, Watson, 
Pascagoula, Fort Adams, Brusly, Bayou Sorrel, Roseland, Gramercy, 
Amite, Baton Rouge, Lettsworth, Pierre Part, New Roads, Salem, 
Franklinton, Addis, Paincourtville, Reserve, Ponchatoula, Kentwood, 
Moss Point, St. Francisville, Greensburg, Felps, Wakefield, Enon, 
Gloster, Slidell, Picayune, Diamondhead, Easleyville, Gautier, 
Gulfport, Ocean Springs, Walker, Woodville, Crossroads, 
Labadieville, Laplace, White Castle, Bay St. Louis, Clinton, McComb, 
Mandeville, Convent, Prairieville, Montpelier, Waveland, Livonia, 
Darlington, St. Martin, Wilmer, Smithdale, and McNeil
329 AM CDT Sun May 2 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of southeast Louisiana and Mississippi, including the 
  following areas, in southeast Louisiana, Ascension, Assumption, 
  East Baton Rouge, East Feliciana, Iberville, Livingston, Northern 
  Tangipahoa, Northwest St. Tammany, Pointe Coupee, Southeast St. 
  Tammany, Southern Tangipahoa, St. Helena, St. James, St. John The 
  Baptist, Washington, West Baton Rouge and West Feliciana. In 
  Mississippi, Amite, Hancock, Harrison, Jackson, Pearl River, Pike, 
  Walthall and Wilkinson.

* Through late tonight

* Rainfall totals of 1 to 3 inches with locally higher amounts are 
  forecast through tonight.

$$

CAB
039 
WGUS64 KLIX 021500
FFALIX

Flood Watch
National Weather Service New Orleans LA
1000 AM CDT Sun May 2 2021

LAZ034>037-039-046>050-056>061-063>072-075>078-MSZ068>071-077-
080>082-022300-
/O.CON.KLIX.FF.A.0004.000000T0000Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
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-Lower Terrebonne-Lower Lafourche-Lower Jefferson-Lower
Plaquemines-Lower 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 Convent, Gonzales, Dexter, Chalmette, 
Covington, Buras, Cut Off, Belle Chasse, White Castle, East New 
Orleans, Gramercy, Bayou Cane, Amite, Pascagoula, Raceland, 
Wakefield, Gloster, Waveland, Easleyville, McComb, McNeil, 
Montpelier, Livonia, Darlington, Gillsberg, Gulfport, Jackson, 
Spillman, Greensburg, Liberty, Port Allen, Diamondhead, Roseland, 
Hammond, Metairie, Salem, Boothville, Galliano, Chauvin, Kenner, St. 
Francisville, Enon, St. Martin, Clinton, Labadieville, Dulac, 
Thibodaux, Yscloskey, Myrtle Grove, Mandeville, Prairieville, 
Violet, Dolorosa, Donaldsonville, Lutcher, Ocean Springs, Robert, 
Bogalusa, Larose, Poplarville, Tylertown, Centreville, Destrehan, 
Baton Rouge, New Roads, Lettsworth, Picayune, Paincourtville, Pointe 
A La Hache, Bay St. Louis, Leeville, Franklinton, Gautier, Slidell, 
Walker, Felps, Laplace, Woodville, Denham Springs, New Orleans, 
Montegut, Wilmer, Golden Meadow, Cocodrie, Venice, Lacombe, 
Plaquemine, Fort Adams, Brusly, Bayou Sorrel, Kentwood, Pierre Part, 
Watson, Houma, Addis, Smithdale, Moss Point, Ponchatoula, 
Crossroads, Norco, Reserve, Port Sulphur, and Empire
1000 AM CDT Sun May 2 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of southeast Louisiana and Mississippi, including the 
  following areas, in southeast Louisiana, Ascension, Assumption, 
  East Baton Rouge, East Feliciana, Eastern Orleans, Iberville, 
  Livingston, Lower Jefferson, Lower Lafourche, Lower Plaquemines, 
  Lower St. Bernard, Lower Terrebonne, Northern Tangipahoa, 
  Northwest St. Tammany, Pointe Coupee, Southeast St. Tammany, 
  Southern Tangipahoa, St. Charles, St. Helena, St. James, St. John 
  The Baptist, Upper Jefferson, Upper Lafourche, Upper Plaquemines, 
  Upper St. Bernard, Upper Terrebonne, Washington, West Baton Rouge, 
  West Feliciana and Western Orleans. In Mississippi, Amite, 
  Hancock, Harrison, Jackson, Pearl River, Pike, Walthall and 
  Wilkinson.

* Through late tonight

* Rainfall totals of 1 to 3 inches with locally higher amounts are 
  forecast through tonight.

* High rainfall rates could overwhelm drainage capacity. Ponding of 
  water in low lying and poor drainage areas can be expected, with 
  flash flooding possible where the heaviest rain falls.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

Be sure to have multiple ways to receive flash flood warnings should 
they become necessary for your area. And remember, never drive 
through flooded roadways as the water may be too deep for safe 
passage.

&&

$$

DM
397 
WGUS64 KLIX 022000
FFALIX

Flood Watch
National Weather Service New Orleans LA
300 PM CDT Sun May 2 2021

LAZ034>037-039-046>050-056>061-063>072-075>078-MSZ068>071-077-
080>082-022100-
/O.CAN.KLIX.FF.A.0004.000000T0000Z-210503T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
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-Lower Terrebonne-Lower Lafourche-Lower Jefferson-Lower
Plaquemines-Lower 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 Convent, Gonzales, Dexter, Chalmette, 
Covington, Buras, Cut Off, Belle Chasse, White Castle, East New 
Orleans, Gramercy, Bayou Cane, Amite, Pascagoula, Raceland, 
Wakefield, Gloster, Waveland, Easleyville, McComb, McNeil, 
Montpelier, Livonia, Darlington, Gillsberg, Gulfport, Jackson, 
Spillman, Greensburg, Liberty, Port Allen, Diamondhead, Roseland, 
Hammond, Metairie, Salem, Boothville, Galliano, Chauvin, Kenner, St. 
Francisville, Enon, St. Martin, Clinton, Labadieville, Dulac, 
Thibodaux, Yscloskey, Myrtle Grove, Mandeville, Prairieville, 
Violet, Dolorosa, Donaldsonville, Lutcher, Ocean Springs, Robert, 
Bogalusa, Larose, Poplarville, Tylertown, Centreville, Destrehan, 
Baton Rouge, New Roads, Lettsworth, Picayune, Paincourtville, Pointe 
A La Hache, Bay St. Louis, Leeville, Franklinton, Gautier, Slidell, 
Walker, Felps, Laplace, Woodville, Denham Springs, New Orleans, 
Montegut, Wilmer, Golden Meadow, Cocodrie, Venice, Lacombe, 
Plaquemine, Fort Adams, Brusly, Bayou Sorrel, Kentwood, Pierre Part, 
Watson, Houma, Addis, Smithdale, Moss Point, Ponchatoula, 
Crossroads, Norco, Reserve, Port Sulphur, and Empire
300 PM CDT Sun May 2 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for Southeast Louisiana and Southwest and 
Coastal Mississippi has been cancelled.

While Isolated showers and storms will continue to be possible 
through tonight, the flash flood threat will be low.

$$

DM

Nearby

Flash Flood Watches in Louisiana, 2021Flash Flood Watches in Mississippi, 2021Every flash flood watch 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.