497
FXUS64 KLIX 201635
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1135 AM CDT Mon Jul 20 2026

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

.KEY MESSAGES...
Updated at 1133 AM CDT Mon Jul 20 2026

- Hot and dry today through much of Tuesday. Highs in the mid 90s
  to near 100 with heat indicies 105-112. Heat headlines for
  Wednesday and Thursday will be contingent on the path of TD2.

- Tropical Depression 2 is forecast to move westward toward our
  general area through midweek. Impacts are still low confidence,
  but an increase in rainfall (mainly south of I-10) with breezy
  conditions along with potential coastal flooding are becoming
  more and more possible with time.

&&

.SHORT TERM...
(Now through Thursday)
Issued at 1133 AM CDT Mon Jul 20 2026

The local area remains on the northwest side of Tropical Depression
Two over the northeastern Gulf and along the southeastern periphery
of an upper ridge centered well to the northwest. Subsidence between
these features, along with dry-air entrainment around the
depression, has maintained mostly clear skies and little radar
activity across the CWA. A few outer bands from TD2 could sneak in
from the west later today, so carrying slight chance to chance POPs
in far easter zones. Surface winds remain generally north to
northwest at 5 to 10 mph which is actually aided in higher than
normal temps as southerly winds increase moisture limits warming.
That combo allows for temps to climb into the middle and upper 90s
this afternoon. Those temperatures and the moisture rich boundary
layer will produce heat index values generally from 105 to 112
degrees. Similar conditions are expected Tuesday, thus have issued a
heat advisory for tomorrow as well.

TD2 is expected to gradually become Tropical Storm Bertha while
moving slowly northwest today, then turn west-northwest as the ridge
to its northwest becomes the dominant steering feature. The
depressions broad circulation, mid level dry air, and limited
organized convection should keep strengthening gradual. Northerly
shear is forecast to increase Tuesday night and Wednesday, likely
halting additional intensification and displacing the deeper
convection and heaviest rainfall south of the circulation center.

On Tuesday, thin outer rainbands may begin reaching eastern portions
of the CWA during the afternoon, although the more organized
rainfall should remain over the coastal waters. The current forecast
brings the circulation across the CWA, generally south of I10
Wednesday afternoon into the overnight period. The timing of TD2 is
still such that still outside the window for TC watches but if any
portion of the CWA gets one, it`ll most likely be the southshore.
For rain, as mentioned earlier, increasing northerly shear and
continued dry-air entrainment are expected to maintain a pronounced
southward displacement of the primary rain shield. The greatest rain
coverage and locally heavy-rain potential should therefore remain
over the Gulf or maybe the immediate southeastern Louisiana coastal
Parishes as the storm passes through. Could even see a scenario
where more of the CWA sees no rain than those that see 1 inch. The
caveat is small changes in the track, shear orientation, or
organization of the cyclone could still shift a heavier band inland.

Water levels will also need to be watched as the system approaches
and local winds strengthen and change direction. A rise of roughly 1
to 3 feet above normal tide levels appears possible in vulnerable
coastal areas and around the tidal lakes, although the location and
timing of the greatest rise will be highly dependent on the exact
track.

MEFFER
&&

.LONG TERM...
(Thursday night through Sunday)
Issued at 1133 AM CDT Mon Jul 20 2026

The tropical system is forecast to continue west across southern
Louisiana Thursday before moving toward southeast Texas. Lingering
bands may continue to rotate across portions of the CWA, especially
coastal Louisiana and areas west of I-55. POPs are generally in the
30 to 50 percent range, but coverage will be uneven and strongly
tied to the placement of individual bands. Winds should also
diminish from east to west as the circulation pulls away.

By Friday, the tropical system should be weakening to the west while
the upper ridge centered to the northwest expands southeastward
across the Gulf Coast. Increasing subsidence should reduce rain
coverage, with only isolated to scattered afternoon convection
expected Friday. Temperatures will respond by returning to the
middle 90s across most inland areas, with lower 90s near the
immediate coast. The ridge is forecast to remain the dominant
feature through the weekend. It may not completely suppress the sea-
breeze and outflow-driven convection typical of late July, so
scattered afternoon storms remain reasonable Saturday and Sunday.
Heat may again become a concern by next weekend. Current blended
guidance supports highs in the middle 90s. Confidence is not yet
high enough to determine whether heat headlines will be needed, as
cloud cover, residual tropical moisture, and the strength and
placement of the ridge remain uncertain.

MEFFER
&&

.AVIATION...
(18Z TAFS)
Issued at 1133 AM CDT Mon Jul 20 2026

CAMs and medium range models indicate that a few rain bands from TD2
may begin passing across eastern portions of the local area.
Therefore, will have PROB30s in those TAFs east of I-55. Otherwise,
VFR and light winds through this taf cycle at all sites.

&&

.MARINE...
Issued at 1133 AM CDT Mon Jul 20 2026

TD2 will be the primary marine concern through Thursday. Northwest
winds of 10 to 15 knots will continue today and tonight with seas 3-
5ft , although isolated showers and thunderstorms could produce
locally higher winds and waves. Conditions will deteriorate from
east to west Tuesday and Tuesday night as the TC begins moving west-
northwest across the north-central Gulf. Winds should increase to 20
to 30 knots, with tropical-storm conditions becoming possible over
the eastern waters Tuesday night and spreading across most marine
zones Wednesday and Wednesday night. Tropical-storm conditions will
be most likely near the circulation center and over the open Gulf
waters. Seas should build to 5 to 10 feet across much of the open
Gulf, with 10 to 15 feet possible near the track of the center.
Conditions over the tidal lakes and protected waters will be lower
than over the open Gulf but may still become quite rough, with
strong gusts near the circulation and within rainbands. The system
should move west of the area Thursday, allowing winds and seas to
diminish considerably from east to west during the afternoon and
evening. By Friday and through the weekend, winds should generally
return to 5 to 10 knots with seas subsiding to around 1 to 3 feet.

MEFFER
&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Tropical Storm Watch for LAZ070-076-078-091.

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

     Heat Advisory from noon to 7 PM CDT Tuesday for LAZ034>037-039-
     046>048-056>058-064-070-071-076>087-089>100.

     Storm Surge Watch for LAZ070-076-078-091.

GM...Tropical Storm Watch for GMZ532-534>536-554-557-575-577.

MS...Tropical Storm Watch for MSZ086>088.

     Heat Advisory until 7 PM CDT this evening for MSZ068>071-077-
     083>088.

     Heat Advisory from noon to 7 PM CDT Tuesday for MSZ068>071-077-
     083>088.

     Storm Surge Watch for MSZ086>088.

GM...Tropical Storm Watch for GMZ534>536-554-557-575-577.

&&

$$

SHORT TERM...ME
LONG TERM....ME
AVIATION...ME
MARINE...ME