Flash Flood Warning 99, NWS New Orleans, LA

Area Forecast Discussion
National Weather Service New Orleans LA
1254 PM CDT Sun Jul 5 2026

...New SHORT TERM, LONG TERM, MARINE...

.KEY MESSAGES...
Updated at 1244 PM CDT Sun Jul 5 2026

- Very normal summer pattern with warm days and scattered to
  numerous daily showers and thunderstorms expected through the
  next several days. Chances of severe weather will be marginal,
  but a few storms each day could become strong to severe with
  gusty winds and/or locally heavy rainfall.

- Waterspout activity will be possible over the coastal waters,
  especially in the early morning hours in conjunction with the
  diurnal cycle.

- Heat stress will be an impact throughout the forecast period
  with near heat advisory conditions each afternoon. The hottest
  timeframe looks to be the latter half of this week.

&&

.SHORT TERM...
(Now through Wednesday night)
Issued at 1244 PM CDT Sun Jul 5 2026

Storm coverage will be more widespread for the next several days.
We always give the when, where and how much, but this is the place
we can give the why. We will discuss features at the H3 level
since this is where one can see the things best that are causing
our weather to occur this week. This is ofcourse reflected
downward, but we will keep it as simple as possible. A very minor
upper short wave trough is rotating through currently causing
moisture to stack vertically wich in turn causes the PW values to
increase. And the higher the PW values, the heavier and more
widespread the rainfall can be. Normally, this feature moving
through would only give one maybe two days of widespread storm
activity, but the larger synoptic upper trough will then come in
behind this, since the short wave is actually moving through the
long wave trough, helping to continue the higher PW values. The
upper trough stands in the flow(like a standing wave), which makes
it stall or actually move very slowly eastward Monday through
Tuesday. The axis of this trough actually moves near our area Wed.
This means it takes 3 full days for this trough axis to move from
the Texarkana region to here. The stronger winds finally round
the base of this trough and cause it to become progressive,
speeding it up toward the east coast. Wed will be our transfer day
meaning our PW values will fall and there won't be any dynamic
load aloft to help storms flourish. This will cause only one thing
to kickstart kinematics for storm development...buoyancy. This is
what we have been working with over the last few days until
today. But this single driver will be back possibly by Wed but
surely as we move into the latter half of this week bringing out
daily ration of storms to around the 30% level once again. Each
day will bring with it the possibility of strong to severe storms.
The chances are low for any one location, but dry air near the H7
level will definitely lend to one or two of these storms having
strong to severe downdrafts causing wet microbursts. Waterspouts
are almost a given in these environments, and this has been the
case lately. But with added help aloft, some of these could form
over marine areas and move inland before dissipating. When
buoyancy is the only driver, waterspouts will normally weaken
once they "feel" land, which is to say the flow is
disturbed/disrupted due to the land mass causing friction to the
flow. With more upper dynamics involved, waterspouts can actually
hold togther long enough to reach the coast before decaying. This
greatly depends on how strong the dynamic load upstairs is, and
today through Wed, it is weak but it is there which means if they
reach the coast, they are almost always weak vorticies but can
still cause havoc a short distance inland. [TE/DSS]

&&

.LONG TERM...
(Thursday through Saturday night)
Issued at 1244 PM CDT Sun Jul 5 2026

Later in the week an H5 ridge will reside over the western portions
of the Atlantic, across Florida and into the northeast Gulf. This
will place our region in a more active southwesterly flow aloft. The
period starts with a weakness over the Midsouth and lower MS River
Valley, which signals an uptick in diurnally driven convection
across the region. POPs for this time will be slightly above typical
CLIMO, especially across southwest MS. And again with the relatively
close proximity to the upper ridge temperatures will likely be a
couple of degrees higher than average. Within the southwesterly flow
aloft, a series of impulses may slide north and east just north of
the CWA. Timing will help keep POPs going during peak heating
through the start of next weekend. Overall, the summer pattern
remains roughly unchanged through the entire long term period.
(Frye/Schlotz)

&&

.AVIATION...
(18Z TAFS)
Issued at 1224 PM CDT Sun Jul 5 2026

TSRA today will be timed in PROB30 groups will keep the
prevailing groups since there will be more coverage today. Most if
not all terminals will be impacted at some time today by TSRA
producing at most MVFR conditions temporarily. SHRA and TSRA
activity will begin to decay with the loss of daytime heating.
Outside TSRA, VFR will be the rule.

&&

.MARINE...
Issued at 1244 PM CDT Sun Jul 5 2026

High pressure in the area bringing WSW to SW winds generally in
the 5-10 knot range; these winds will only generate seas in the
1-2 foot range. Summertime diurnal cycling will bring offshore
thunderstorms that will almost assuredly carry waterspout activity
as well as increased winds and associated localized heavier seas.

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&

SHORT TERM...DS
LONG TERM....DS
AVIATION...DS
MARINE...DS

Special Weather Statement
National Weather Service New Orleans LA
233 PM CDT Sun Jul 5 2026

LAZ081-083-084-051945-
Central Tangipahoa LA-Northern Livingston LA-Southern Livingston LA-
233 PM CDT Sun Jul 5 2026

...A STRONG THUNDERSTORM WILL IMPACT PORTIONS OF NORTHEASTERN
LIVINGSTON AND WEST CENTRAL TANGIPAHOA PARISHES THROUGH 245 PM CDT
...

At 233 PM CDT, Doppler radar was tracking a strong thunderstorm near
Springfield, or 12 miles southwest of Hammond, moving southeast at 20
mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Livingston, Albany, Springfield, Natalbany, and Killian.

This includes the following Interstates...
 Interstate 12 between mile markers 23 and 34.
 Interstate 55 in Louisiana between mile markers 33 and 34.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

If on or near marine areas, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles from
the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not be
caught on the water in a thunderstorm.

&&

LAT...LON 3055 9047 3049 9055 3036 9053 3038 9083
      3057 9068
TIME...MOT...LOC 1933Z 300DEG 18KT 3043 9064

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

KLG

Special Weather Statement
National Weather Service New Orleans LA
249 PM CDT Sun Jul 5 2026

LAZ057-058-084-086-098>100-052015-
Central St. Charles LA-Southern Livingston LA-Upper St. Charles LA-
St. John The Baptist LA-St. James LA-Lower St. Charles LA-
Eastern Ascension LA-
249 PM CDT Sun Jul 5 2026

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF ST. JOHN THE BAPTIST,
EAST CENTRAL ASCENSION, NORTHEASTERN ST. JAMES, NORTHWESTERN ST.
CHARLES AND SOUTHEASTERN LIVINGSTON PARISHES THROUGH 315 PM CDT
...

At 249 PM CDT, Doppler radar was tracking a cluster of strong
thunderstorms 8 miles north of Garyville, or 8 miles north of
Reserve, moving southeast at 15 mph.

HAZARD...Wind gusts up to 40 to 50 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Reserve, Hahnville, Laplace, Gramercy, Lutcher, Killona, Norco,
Montz, Edgard, North Vacherie, Garyville, Wallace, Taft, New Sarpy,
Whitehall, Destrehan, and Killian.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 191 and 217.
 Interstate 55 in Louisiana between mile markers 1 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

If on or near marine areas, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles from
the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not be
caught on the water in a thunderstorm.

&&

LAT...LON 3021 9074 3033 9068 3036 9060 3029 9054
      3021 9055 3021 9048 3023 9046 3017 9039
      3010 9038 3008 9033 2997 9035 2994 9056
      3002 9077
TIME...MOT...LOC 1949Z 322DEG 13KT 3019 9059

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...50 MPH

KLG

Special Weather Statement
National Weather Service New Orleans LA
256 PM CDT Sun Jul 5 2026

LAZ076-079-080-082-MSZ077-083-084-086-087-052045-
Southeast St. Tammany LA-Lower Tangipahoa LA-Northern St. Tammany LA-
Southwestern St. Tammany LA-Southern Harrison MS-Northern Hancock MS-
Southern Hancock MS-Northern Harrison MS-Pearl River MS-
256 PM CDT Sun Jul 5 2026

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF ST. TAMMANY AND
SOUTHEASTERN TANGIPAHOA PARISHES, NORTHWESTERN HARRISON, HANCOCK AND
SOUTHERN PEARL RIVER COUNTIES THROUGH 345 PM CDT
...

At 256 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Picayune to 8 miles southwest of
Mandeville. Movement was southeast at 35 mph.

HAZARD...Wind gusts up to 40 to 50 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Slidell, Mandeville, Picayune, Bay St. Louis, Covington, Waveland,
Eden Isle, Diamondhead, Pearl River, Abita Springs, Madisonville,
Kiln, Pearlington, Lacombe, Shoreline Park, Stennis Space Center, and
Slidell Airport.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 259 and 273.
 Interstate 10 in Mississippi between mile markers 1 and 21.
 Interstate 12 between mile markers 58 and 84.
 Interstate 59 in Louisiana between mile markers 1 and 11.
 Interstate 59 in Mississippi between mile markers 1 and 18.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

If on or near marine areas, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles from
the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not be
caught on the water in a thunderstorm.

&&

LAT...LON 3065 8934 3065 8928 3051 8925 3026 8935
      3024 8940 3017 8943 3013 8958 3013 8964
      3015 8963 3017 8968 3015 8975 3023 8988
      3024 8999 3030 9003 3036 9019 3034 9024
      3043 9032 3050 8995 3071 8955 3072 8934
TIME...MOT...LOC 1956Z 315DEG 29KT 3050 8966 3027 9015

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

KLG

Special Weather Statement
National Weather Service New Orleans LA
319 PM CDT Sun Jul 5 2026

LAZ056>058-085-086-094-098>100-052100-
Central St. Charles LA-Western Ascension LA-Assumption LA-
Upper St. Charles LA-St. John The Baptist LA-St. James LA-
Upper Lafourche LA-Lower St. Charles LA-Eastern Ascension LA-
319 PM CDT Sun Jul 5 2026

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF SOUTHWESTERN ST. JOHN
THE BAPTIST, SOUTHWESTERN ASCENSION, ST. JAMES, ST. CHARLES, NORTH
CENTRAL LAFOURCHE AND NORTHEASTERN ASSUMPTION PARISHES THROUGH 400 PM
CDT
...

At 319 PM CDT, Doppler radar was tracking strong thunderstorms
capable of producing waterspouts over marine areas along a line
extending from near Convent to near Luling. Movement was southeast at
15 mph.

HAZARD...Waterspouts, wind gusts up to 40 to 50 mph, and half inch
         hail.

SOURCE...Radar indicated.

IMPACT...Waterspouts can easily overturn boats and create locally
         hazardous waters. Gusty winds could knock down tree limbs
         and blow around unsecured objects. Minor damage to outdoor
         objects is possible.

Locations impacted include...
Gonzales, Donaldsonville, Napoleonville, Hahnville, Reserve, Laplace,
Gramercy, Lutcher, Sorrento, Montz, Luling, Garyville, Boutte,
Chackbay, Destrehan, Killona, Norco, Paradis, Des Allemands, and
Edgard.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 180 and 187.
 Interstate 310 between mile markers 4 and 11.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

If on or near marine areas, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles from
the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not be
caught on the water in a thunderstorm.

&&

LAT...LON 3015 9103 3020 9093 3008 9059 3004 9038
      2984 9023 2977 9021 2976 9023 2974 9036
      2986 9093 2992 9112
TIME...MOT...LOC 2019Z 317DEG 15KT 3005 9084 2989 9031

WATERSPOUT...POSSIBLE
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH

KLG

Special Weather Statement
National Weather Service New Orleans LA
321 PM CDT Sun Jul 5 2026

LAZ064-070-077-078-087-089-090-092-098>100-052100-
Central Plaquemines LA-Western Orleans LA-Upper St. Bernard LA-
Central Jefferson LA-Eastern Orleans LA-Central St. Charles LA-
Upper Plaquemines LA-Lower St. Bernard LA-Upper St. Charles LA-
Upper Jefferson LA-Lower St. Charles LA-
321 PM CDT Sun Jul 5 2026

...STRONG THUNDERSTORMS WILL IMPACT PORTIONS OF NORTHWESTERN ST.
BERNARD, NORTHEASTERN ST. CHARLES, ORLEANS, NORTHERN JEFFERSON AND
NORTHWESTERN PLAQUEMINES PARISHES THROUGH 400 PM CDT
...

At 321 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Eden Isle to 7 miles east of Laplace.
Movement was southeast at 25 mph.

HAZARD...Wind gusts up to 40 to 50 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
New Orleans, Kenner, Chalmette, Avondale, Metairie, Marrero, Harvey,
East New Orleans, Timberlane, Belle Chasse, Jefferson, Gretna,
Harahan, Westwego, Lake Catherine, River Ridge, Ama, St. Rose,
Elmwood, and Violet.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 216 and 256.
 Interstate 310 between mile markers 1 and 3.
 Interstate 510 between mile markers 1 and 3.
 Interstate 610 between mile markers 1 and 4.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

If on or near marine areas, get out of the water and move indoors or
inside a vehicle. Remember, lightning can strike out to 10 miles from
the parent thunderstorm. If you can hear thunder, you are close
enough to be struck by lightning. Move to safe shelter now! Do not be
caught on the water in a thunderstorm.

&&

LAT...LON 3004 9038 3008 9025 3005 9006 3009 8997
      3018 8988 3014 8982 3018 8975 3017 8972
      3017 8962 3014 8960 3005 8969 3001 8970
      3001 8982 2996 8980 2996 8969 2989 8978
      2984 9023
TIME...MOT...LOC 2021Z 303DEG 22KT 3016 8977 3010 9035

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...50 MPH

KLG

Special Weather Statement
National Weather Service New Orleans LA
324 PM CDT Sun Jul 5 2026

LAZ034-047-048-052100-
Pointe Coupee LA-West Baton Rouge LA-East Baton Rouge LA-
324 PM CDT Sun Jul 5 2026

...A STRONG THUNDERSTORM WILL IMPACT PORTIONS OF WEST BATON ROUGE,
SOUTHEASTERN POINTE COUPEE AND SOUTHWESTERN EAST BATON ROUGE PARISHES
THROUGH 400 PM CDT
...

At 324 PM CDT, Doppler radar was tracking a strong thunderstorm over
Port Allen, moving southeast at 15 mph.

HAZARD...Winds in excess of 40 mph and pea size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Baton Rouge, Baker, Port Allen, Brusly, Livonia, Maringouin,
Westminster, Merrydale, Erwinville, Brownfields, Gardere, Inniswold,
and Baton Rouge Airport.

This includes the following Interstates...
 Interstate 10 in Louisiana between mile markers 144 and 162.
 Interstate 12 between mile markers 1 and 4.
 Interstate 110 in Louisiana between mile markers 1 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3058 9153 3065 9132 3051 9103 3041 9106
      3034 9117 3046 9144 3050 9148 3049 9152
      3051 9156
TIME...MOT...LOC 2024Z 320DEG 14KT 3046 9119

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

KLG