940
FXUS64 KLIX 071721
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1221 PM CDT Mon Jul 7 2025

...New AVIATION...

.SHORT TERM...
(Today through Wednesday night)
Issued at 1106 PM CDT Sun Jul 6 2025

Late afternoon and evening rainfall across southwest Mississippi
and the Pearl River basin may locally enhance low-level RH values
which in combination with clearing skies and near-calm winds could
result in light patchy fog development across areas near water
bodies and low-lying areas. However, dense fog is unlikely to
develop given current guidance. McComb is already 69/68 and
Bogalusa is 74/71 from the rain-cooled air with calm winds which
could lend a bit more confidence we`ll see these patchy fog
conditions, but nonetheless significant impacts are not
anticipated.

A weak upper trough centered just off the coast of Louisiana is
the primary feature that locally enhanced more scattered storm
coverage on Sunday, and we can expect relatively more of the same
today. The key difference today does appear to be that the best
forcing with this upper trough will continue to gradually move
away which could limit coverage ever so slightly compared to
yesterday, but HREF guidance continues to pinpoint highest PoPs of
60-70% focused along the Atchafalaya Basin extending east to the
I-55 corridor. Though there was some showers and storms that
attempted to fire up along the lake/sea breeze in St. Tammany and
coastal MS on Sunday, the lake shadow and drier air filtering in
from the northeast was an inhibitor and this should still be true
today so PoPs are closer to 30-50%.

By Tuesday, the upper trough will have backed away and weakened
over the northwest Gulf allowing rising mid-level heights and high
pressure to nose itself farther west over the northern Gulf coast.
Latest 00z guidance continues to suggest Tuesday will carry the
least amount of storm coverage and thus PoPs have been dropped
10-15% below NBM guidance to reflect the lower confidence in
measurable precipitation. That said, PoPs are still in the 40-60%
range, especially along and west of the I-55 corridor where
moisture and less suppressive atmospheric conditions will still be
present.

Our attention then turns to a weak shortwave trough currently
situated over the Prairie Provinces of Canada which will dip down
around the eastern periphery of the rebuilding SW CONUS ridge on
Tuesday. This weak shortwave will arrive to the Mid Mississippi
River Valley by Wednesday, slow down as it gets stuck in between
the ridges on either side of it, and begin to lose its coherence.
As it does so. This will begin the gradual trend back up in PoPs
each afternoon starting Wednesday afternoon and continuing into
the latter half of the week.

&&

.LONG TERM...
(Thursday through Sunday night)
Issued at 1106 PM CDT Sun Jul 6 2025

During the second half of the week, deep moisture will increase
across the area with precipitable water forecast to be near or
just above 2 inches across most of the area. This should lead to
a further increase in convective coverage with storms becoming
more numerous to widespread Thursday and Friday. The increase in
moisture will also lead to potential for more efficient rainfall.
While widespread heavy rain is not forecast, individual storms
will be capable of producing high rainfall rates with a couple
inches of accumulation in a relatively short period of time.

By the weekend, it`s less clear whether we`ll see this troughing
linger and continue to enhance afternoon PoPs or if the ridge will
nose back in enough to allow temperatures to nudge back closer to
the mid to upper 90s. Regardless, the muscle memory of this
pattern continues to support persistence forecasts of near or
slightly above normal temperatures with elevated chances for
afternoon storms each day, and that will continue until we see a
considerable shift to the longwave weather pattern at a time TBD.

&&

.AVIATION...
(18Z TAFS)
Issued at 1216 PM CDT Mon Jul 7 2025

Currently VFR conditions across all terminals, expected to remain
so through the period. Exception will be areas of convection in
the vicinity of terminals that may lower CIGs and VIS to MVFR for
the duration of the convection.

&&

.MARINE...
Issued at 1106 PM CDT Sun Jul 6 2025

Marine conditions will be benign through the period outside of any
localized impacts from convection. Winds will remain light out of
the south to southwest in an onshore direction through the work
week. A fairly typical summertime convective pattern is expected
with showers and storms developing during the late night, peaking
during the morning hours, and diminishing through the afternoon and
evening. Storm coverage over the waters will increase in coverage
during the morning hours each morning starting Wednesday into the
weekend with widespread storms most likely on Thursday.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  71  92  72  92 /  20  50  10  70
BTR  73  92  74  93 /  10  50  10  70
ASD  73  93  73  92 /  10  40  10  70
MSY  77  93  78  93 /  10  50  10  70
GPT  75  91  75  92 /  10  30  10  60
PQL  73  92  73  92 /  10  30  20  60

&&

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

$$

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