252
FXUS64 KLIX 032048
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
348 PM CDT Mon Jun 3 2024

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

.SHORT TERM...
(This evening through Tuesday night)
Issued at 335 PM CDT Mon Jun 3 2024

Upper pattern is a bit west-northwesterly across the area with a
shortwave to the northwest across Kansas, and a stronger trough
across the Pacific Northwest. Isolated precipitation tried to
develop around 18z, but with low level flow from the south and
upper flow from the northwest, it appears that shear has stopped
most or all of the updrafts from becoming deep up to this point.
Temperatures at 3 PM CDT were generally in the upper 80s with dew
points in the lower and middle 70s.

Main concerns over the next 36 hours will be the potential for
mesoscale convective systems to the northwest of the area to
travel southeastward and reach the area. One such area is
currently over Kansas. Most guidance dissipates this complex
during the evening, but the runs of the HRRR since 12z bring it
pretty close to the CWA before dissipating it around midnight.
While we currently aren`t carrying precipitation mention across
southwest Mississippi late this evening, threat is not zero.

A somewhat more significant threat appears to be possibly shaping
up for the afternoon hours tomorrow, as a second complex is
forecast to develop over Oklahoma after midnight tonight and
follow much of the same track southeastward. While most guidance
doesn`t indicate this system reaching the area tomorrow, the
recent runs of the HRRR have it reaching the area around midday
tomorrow, and this does have the support of the ECMWF operational
model. Forecast soundings from the GFS do show potential for the
cap to be broken with CAPE values exceeding 3000 J/kg, low level
lapse rates of 7.5 to 8C/km and DCAPE values exceeding 1300 across
northern portions of the area. SPC on their midday Day 2 update
spread the Marginal Risk into our area, and can`t really discount
it. So, we will continue carrying thunderstorm chances for
tomorrow across the area, although the GFS/NAM solutions argue
dry. The HRRR solution has it through the CWA by about 02z
Wednesday, but tends to be a bit slow, especially if it becomes
cold pool dominant, so a dry forecast for Tuesday night isn`t
totally unreasonable.

Don`t see much need to diverge much from NBM temperature numbers,
although might nudge overnight lows up a bit based on
verification.

&&

.LONG TERM...
(Wednesday through Sunday night)
Issued at 335 PM CDT Mon Jun 3 2024

As has been the case for the last week or more, ridging to the
west of the local area and troughing to the east, global models
have struggled to agree. Timing of shortwaves and/or convective
complexes lead to a low confidence in details. The operational
ECMWF is the wetter solution for Wednesday and Thursday, then
dries out for the weekend. The operational GFS is comparatively
dry for Wednesday and Thursday, then becomes the wetter model for
the weekend. The current NBM deterministic numbers trend toward
the ECMWF solution, but it is not a high confidence forecast at
this time.

Until a definitive trend regarding precipitation chances becomes
apparent, can`t see making large changes in the NBM deterministic
temperature forecast.

&&

.AVIATION...
(18Z TAFS)
Issued at 1226 PM CDT Mon Jun 3 2024

Fairly well developed cumulus field this afternoon may
occasionally produce ceilings near FL025 or FL030. Cloud streets
are moving northward, and radar echoes are primarily north and
east of a low level convergence boundary extending from near KMOB
to the north-northwest across extreme eastern MS. Will carry VCTS
at the western terminals (KBTR, KMCB, KHDC, KHUM) this afternoon,
but the threat is non-zero elsewhere. Any convection that develops
should dissipate toward sunset.

Some concern about additional convection as at least a few CAMs
bring mesoscale convective complexes southeastward late this
evening and again during the day on Tuesday. The models showing
one this evening would mainly impact KMCB, with the 2nd on Tuesday
afternoon potentially impacting most terminals. At this time,
confidence in those solutions is much too low to include in
forecast at this time. Any flight restrictions below MVFR
overnight would primarily be at KMCB, where IFR ceilings are
possible. Any restrictions should improve by mid-morning Tuesday.

&&

.MARINE...
Issued at 335 PM CDT Mon Jun 3 2024

Main marine concern over the next few days is likely to be the
potential for thunderstorms, with one such period possible
tomorrow afternoon. Confidence in timing is fairly low. There
could be brief periods where Small Craft Exercise Caution
headlines are necessary. One would be around sunrise tomorrow over
the western waters. That one is rather borderline, so we`ll let
the evening shift take a look at that one before a final decision.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  70  89  71  90 /  20  40   0  40
BTR  76  93  76  94 /  10  30   0  30
ASD  75  91  75  93 /  10  40   0  30
MSY  77  90  77  92 /  10  30   0  30
GPT  77  88  77  89 /  20  40  10  30
PQL  74  90  75  91 /  20  30   0  20

&&

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

$$

SHORT TERM...RW
LONG TERM....RW
AVIATION...RW
MARINE...RW