Severe Thunderstorm Warning 91, NWS New Orleans, LA

Area Forecast Discussion
National Weather Service New Orleans LA
157 PM CDT Fri Jun 19 2026

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

.KEY MESSAGES...
Updated at 1242 PM CDT Fri Jun 19 2026

- Extreme heat is expected this weekend and into next week. Heat
  advisories have been issued for heat index values of around 110
  degrees for today. Heat advisories may be re-issued over the
  weekend and into next week.

&&

.SHORT TERM...
(Now through Monday night)
Issued at 1242 PM CDT Fri Jun 19 2026

Through Monday night, the forecast area will remain on the
northern periphery of a broad deep layer ridge centered over the
central and northern Gulf. The influence of this ridging will be
felt in two ways, overall lower rain chances each day and much
warmer temperatures. Going into the rain chances, there will be a
fairly defined north to south oriented gradient as stronger mid-
level capping aloft prohibits convective development for areas
mainly to the south of Lake Pontchartrain. The only chance for
these areas to see any additional rainfall in the coming days
looks to be on Saturday when an outflow driven convective complex
descends southward from the Lower Mississippi Valley. However, the
intensity of the convective complex in terms of rainfall coverage
will begin to wane as it moves into coastal Louisiana and the
offshore waters due to the significantly drier air aloft it will
encounter.

For areas north of the I-10/12 corridor, PWATS will be
closer to average through the weekend and a weaker mid-level cap
will allow for some modest MLCAPE of 1000 to 1500 J/KG to develop
each afternoon. Any convective activity will develop late in the
afternoon and evening hours when the convective temperature in the
mid 90s is finally reached. This will be true for today, Saturday,
and Sunday with the highest rain chances occurring on Saturday
when a weak mid to upper level vort max riding along the northern
periphery of the ridge passes through the Lower Mississippi
Valley. The latest CAMS indicate that a mesoscale convective
system will develop over the ArkLaMiss region and then follow the
theta-e gradient south-southeast into the CWA by Saturday evening.
The biggest concern from the complex of storms will be
damaging wind gusts and locally heavy rainfall falling on already
saturated soils, leading to flash flooding issues late Saturday.
Once the MCS dies off Saturday evening, conditions will begin to
trend much drier overall as the influence of the ridge grows.
Sunday will see scattered diurnally forced convection north of
I-10/12 that will occasionally produce a strong wind gust or
brief downpour, but overall the trend will be for weaker updrafts
and storms. By Monday, PWATS will fall below average across the
entire region and any convection will struggle to break the
increasingly strengthening mid-level capping inversion in place. A
largely dry forecast is in place for Monday.

The other issue of concern is the growing threat of an extended
period of extreme heat. Temperatures will easily climb into the
low to mid 90s each day and dewpoints will remain fairly high in
the upper 70s and lower 80s through Monday. These high dewpoints
will allow heat index values to climb to between 105 and 110 each
day through Monday. Although a heat advisory has not been issued
for tomorrow, there is a high likelihood that one will be issued
for Saturday with the overnight forecast package. HeatRisk will
also be in the moderate to major range each day and this indicates
an increased risk of heat illnesses for those conducting outdoor
activities.

&&

.LONG TERM...
(Tuesday through Thursday night)
Issued at 1242 PM CDT Fri Jun 19 2026

Tuesday will see little overall change from the weekend with
continued hot temperatures and low rain chances as a broad deep
layer ridge remains in firm control of the Gulf South. Heat index
values will once again climb to between 105 and 110 and only some
isolated afternoon convection will develop as temperatures climb
into the low to mid 90s. Any convection will be most likely across
the northern third of the CWA where the mid-level cap will be the
weakest, although still quite strong.

Wednesday and Thursday will see the influence of the ridge begin
to decrease as a broad northern stream longwave trough axis digs
into the eastern half of the CONUS. This will help to flatten out
the ridge in the Gulf and reduce the strength of the mid-level
cap over the area. A north-south gradient of rain chances will
continue to remain in place, but overall convective coverage will
increase back to more typical levels for late June. Rain chances
will range from 20 to 30 percent south of New Orleans to 40 to 50
percent north of the I-10/12 corridor each day. The convection
will be very diurnal with coverage peaking in the afternoon hours
as highs climb into the lower 90s. Lingering mid-level dry air
entrainment into a few of the storms could lead to a few damaging
wind events associated with wet microbursts both days. The
slightly cooler temperatures should also help to push heat index
values back to around 105 degrees, or just below heat advisory
levels on Wednesday and Thursday.

&&

.AVIATION...
(18Z TAFS)
Issued at 1242 PM CDT Fri Jun 19 2026

Outside of convective concerns late tonight at MCB where some MVFR
visibility impacts and gusty winds could briefly occur, prevailing
VFR conditions will be the rule through the evening hours. Later
tonight, between 10z and 13z, a brief period of low stratus could
produce ceilings near 1000 feet at MCB and possibly HDC as weak
elevated inversion forms. This inversion will quickly mix out
after 13z with prevailing VFR conditions returning.

&&

.MARINE...
Issued at 1242 PM CDT Fri Jun 19 2026

A prevailing southerly flow will be in place through the middle of
next week as a broad surface high pressure system dominates the
Gulf.  Winds will generally range from 10 to 15 knots through the
period and seas will range from 2 to 4 feet.  Overall, no
significant impacts to maritime activities are anticipated through
the middle of next week.

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory until 7 PM CDT this evening for LAZ034>037-039-
     046>048-056>058-064-070-071-076>087-089>100.

GM...None.
MS...Heat Advisory until 7 PM CDT this evening for MSZ068>071-077-
     083>088.

GM...None.
&&

SHORT TERM...PG
LONG TERM....PG
AVIATION...PG
MARINE...PG

Special Weather Statement
National Weather Service New Orleans LA
458 PM CDT Fri Jun 19 2026

MSZ085-192215-
Northern Jackson MS-
458 PM CDT Fri Jun 19 2026

...A STRONG THUNDERSTORM WILL IMPACT PORTIONS OF NORTHEASTERN JACKSON
COUNTY THROUGH 515 PM CDT
...

At 458 PM CDT, Doppler radar was tracking a strong thunderstorm near
Hurley, or 15 miles northeast of Escatawpa, moving east at 20 mph.

HAZARD...Wind gusts up to 50 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects.

Locations impacted include...
Hurley.

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 3061 8853 3073 8850 3074 8842 3072 8841
      3057 8841
TIME...MOT...LOC 2158Z 281DEG 17KT 3069 8843

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...50 MPH

CAB