577
FXUS64 KLIX 250915
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
415 AM CDT Sat May 25 2024

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

.SHORT TERM...
(Today through Sunday)
Issued at 400 AM CDT Sat May 25 2024

Upper ridge centered over Mexico early this morning with a
shortwave moving eastward across Mississippi north of Interstate
20. Convection associated with that shortwave is well north of the
local area and isn`t expected to become a factor in today`s
weather other than to produce cirrus across the area. Light
southerly flow continues across the area, making for a rather warm
and humid night. Temperatures at 3 AM CDT were in the mid 70s to
lower 80s, with dew points only a degree or two lower at best for
most areas.

Main concern with this forecast package in the short term will be
heat related. High temperatures should be in the lower to middle
90s across most of the area both today and Sunday, although a sea
breeze cold hold areas right at the coast to the upper 80s if the
sea breeze kicks in soon enough. Maximum heat index values are
expected to top out generally in the 100 to 105F range both days.
This is short of our advisory criteria (108F), but with it being
the first time this season that much of the area will be
experiencing those levels of discomfort, having a way to keep
hydrated and cool off will be helpful. Overnight lows will be in
the 70s, which is about 5-10F above normal for late May.

&&

.LONG TERM...
(Sunday night through Friday)
Issued at 400 AM CDT Sat May 25 2024

While ridging remains centered over Mexico, changes around the
periphery of the ridge will be dictating the weather across the
local area. Unfortunately, the global models aren`t in
particularly good agreement on the details. A northern stream
shortwave is expected to push a cold front southward toward the
local area over the next few days, but the ECMWF operational
solution is much more aggressive with this feature, bringing
precipitation chances into northern portions of the area Sunday
night. The GFS solution is much drier, and the majority of ECMWF
ensemble members favor a drier solution, with the NBM numbers
supporting this. We`ll keep the forecast dry until Monday
afternoon, when soundings are at least a bit more supportive of
convective development. Beyond that point, the operational global
models essentially flip their positions when it comes to rain
chances, with the GFS solution being more favorable to development
than the ECMWF. A majority of ECMWF ensemble members show no
significant precipitation chances for most of the CWA beyond
Monday. NBM numbers produce at least low end chances for afternoon
convection through midweek, which isn`t a major departure from
what was in previous package.

We will continue to see uncomfortable humidity levels on Memorial
Day, with maximum heat index values pushing pretty close to
advisory levels across western portions of the area if convection
fails to develop. With a trough deepening across the eastern third
of the country early in the week, the northwesterly mid level flow
across the area should push somewhat drier air into the area. This
may happen as early as Tuesday, with more agreement on it
occurring Wednesday and beyond. This should at least knock down
humidity levels with dew points falling into the 60s on Wednesday
through Friday. That will result in cooler overnight lows, as well
as possibly knocking a degree or two off of high temperatures.
However, temperatures will still remain near or above normal.
Didn`t see an obvious target of opportunity to diverge from NBM
numbers.

&&

.AVIATION...
(06Z TAFS)
Issued at 1131 PM CDT Fri May 24 2024

VFR conditions will eventually drop to MVFR respectively. MCB
continues to have a lower VIS signal closer to sunrise. Flight
categories will improve shortly after sunrise on Saturday. Winds
will again remain southerly or perhaps a little west of due south
and light generally less than 10 knots. (Frye)

&&

.MARINE...
Issued at 400 AM CDT Sat May 25 2024

Onshore flow likely to predominate for much of at least the first
half of the forecast period. As the frontal boundary pushes
southward toward the waters, the gradient may tighten just enough
to necessitate Small Craft Exercise Caution headlines late Sunday
night into Monday across a large portion of the waters. It doesn`t
appear that the open waters will see a clear frontal passage on
Tuesday (and might not for the next 4 months or so). As the front
washes out, the pressure gradient becomes weak enough that winds
will be driven by differential heating processes that we normally
see during the summer.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  91  71  92  73 /  10   0   0  10
BTR  95  76  95  78 /  10   0   0   0
ASD  93  75  93  77 /   0   0   0   0
MSY  93  77  92  78 /   0   0   0   0
GPT  89  76  90  77 /   0   0   0   0
PQL  91  73  91  76 /  10   0   0   0

&&

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

$$

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