Marrero, Louisianna 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

152
FXUS64 KLIX 172019
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
319 PM CDT Thu Apr 17 2025

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

.SHORT TERM...
(This evening through Saturday night)
Issued at 247 PM CDT Thu Apr 17 2025

Little change in thinking from the previous forecast package as a
strong deep layer ridge axis continues to dominate the Gulf South
through Saturday night. Persistent onshore flow from the Gulf will
advect in a warm and moist airmass in the low levels, but strong
subsidence aloft will keep the mid and upper levels warm and dry.
The end result will be a continued strong mid-level capping
inversion that will keep any rain chances at bay through Saturday
night. There will continue to be scattered to broken strato-
cumulus development beneath the elevated inversion with the
greatest cloud cover expected on Saturday. Temperatures will also
continue to run above average due to a combination of the deep
layer subsidence associated with the ridge and warm air advection
from the Gulf. Highs will easily climb into the mid to upper 80s
each day. Lows will warm from the upper 50s and 60s tonight into
the upper 60s and lower 70s by Saturday night as dewpoints
continue to rise. Friday and Saturday will see a return of more
muggy conditions across the region.


&&

.LONG TERM...
(Sunday through Wednesday night)
Issued at 247 PM CDT Thu Apr 17 2025

A vigorous shortwave trough will eject out of the southern Plains
and into the Midwest Sunday into Monday, and this will drive a
frontal boundary toward the forecast area over this period. As the
front moves into the area, the parent trough axis will quickly
pull to the northeast and a prevailing southwesterly flow pattern
will develop in the mid to upper levels. The end result will be
the front stalling across the area on Monday and then lingering
over the region through Wednesday. This pattern will bring a more
unsettled weather pattern to the area as the front serves as a
focusing mechanism for shower and thunderstorm development.

Sunday into Sunday night will be largely dry with only isolated
shower and thunderstorm activity expected for areas generally
north of I-10 and west of I-55. This region of the forecast area
will have the weakest capping aloft and just enough forcing
associated with the approaching trough and front to drive some
convective development. Otherwise, it a warm and muggy day with
highs climbing back into the mid 80s and lows only dipping to
around 70.

Monday will see the highest probability of shower and
thunderstorm activity as the aforementioned shortwave trough
slides through the region. Fortunately, shear profiles will remain
weak. This will keep any convective activity on the weaker side
with the main concerns being brief heavy downpours and lightning
strikes. Coverage will be fairly decent, especially north of I-10,
as periods of showers and thunderstorms move through. By Monday
night, the convective activity will shift to the east with only
isolated to widely scattered convection. This is due to the trough
axis departing to the east and some weak upper level negative
vorticity and dry air advection in the mid and upper levels taking
hold. Temperatures will also be slightly cooler with lows falling
into the mid to upper 60s.

Tuesday and Wednesday will see a series of weak upper level
impulses embedded within the broader southwest flow pattern pass
through the region. These impulses will interact with the
dissipating front stalled over the region to produce diurnal
convective activity each day. At this time, the boundary looks to
be stalled over the northern half of the CWA, and PoP values are
highest for this area. Temperatures will also be near to slightly
above average both days, but record heat is no longer anticipated
due to the increased cloud cover and convection.

&&

.AVIATION...
(18Z TAFS)
Issued at 247 PM CDT Thu Apr 17 2025

The CU field continues to develop across the region, however
ceilings are generally remaining VFR at around or just above 3K
FT. CU will dissipate as sunset approaches, however patchy MVFR
ceilings and thin BR may develop at inland terminals toward
sunrise only to dissipate a few hours later. Gusty winds will
decrease late this afternoon and overnight then increase again
through the morning hours Saturday while remaining south to SE.

&&

.MARINE...
Issued at 247 PM CDT Thu Apr 17 2025

A gradually tightening pressure gradient between a ridge over the
northern Gulf and a low deepening over the southern Rockies and
Plains will allow for increased winds starting tonight and
continuing through Sunday. These winds will climb to between 15 an
20 knots in the open Gulf waters and close to 15 knots in the
sounds and tidal lakes. Additionally, a decent fetch across the
Gulf will allow 1 to 2 feet of swell to add onto the wind waves
offshore, leading to seas of 6 to 8 feet over the weekend. These
conditions will produce fairly rough sea states on Saturday and
Sunday. The pressure gradient will ease on Monday as the low pulls
to the northeast, and this will allow onshore winds to fall back
below 10 knots. Seas will also gradually decrease to 2 to 3 feet
by Tuesday evening.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  61  87  65  85 /   0   0   0   0
BTR  65  88  69  86 /   0   0   0   0
ASD  64  83  68  83 /   0   0   0   0
MSY  67  83  70  83 /   0   0   0   0
GPT  65  78  69  79 /   0   0   0   0
PQL  63  79  66  79 /   0   0   0   0

&&

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

$$

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