Pearlington, Mississippi Weather Forecast Discussion

373
FXUS64 KLIX 070517
AFDLIX
Area Forecast Discussion
National Weather Service New Orleans LA
1217 AM CDT Sun Sep 7 2025
...New SHORT TERM, LONG TERM, AVIATION, MARINE...
.SHORT TERM...
(Tonight through Monday night)
Issued at 1153 PM CDT Sat Sep 6 2025
The weak surface frontal boundary continues to gradually sink south
across the northern Gulf Coast. Dew point temperatures are gradually
dropping as drier air gets ushered in by light northerly flow behind
the front. Dew points have fallen about 4-8 degrees north of the I-
10/12 corridor compared to 24 hours ago thus far. Dews fall into the
mid 60s to upper 50s through the day on Sunday as the continental
drier air mass sinks to the south. PWATs will be near the 25th
percentile for the area (0.8 to 1.0 inches) which will allow daytime
humidities to crater to near 50% on Sunday and into the 30-45% range
on Monday as diurnally-driven vertical mixing occurs. This will
suppress cu development and any cu development will predominantly be
limited in growth by dry air despite modest surface-based CAPE (1000-
2000 j/kg). Only area with PoPs exceeding 15% are near the mouth of
the Atchafalaya Basin, enhanced by the sea breeze in Terrebonne and
Lafourche Parishes on Sunday. PoPs near 0% areawide on Monday as
those PWATs bottom out.
Limited cloud coverage will promote highly diurnal temperature
fluctuations with highs in the upper 80s to near 90F along the
coast. Given stronger mixing with elevated northerly winds Sunday
night into Monday morning, radiational cooling will be less
efficient so NBM deterministic is being maintained which is already
closer to the 25th percentile within NBM suite for MinT.
&&
.LONG TERM...
(Tuesday night through Saturday night)
Issued at 1153 PM CDT Sat Sep 6 2025
By Monday and into Tuesday, the main story is another reinforcing
shot of the drier/cooler air builds into the region. Took a very
close look at two items here:
Min temperatures Monday and Tuesday morning and dewpoints Monday
and Tuesday afternoon. For lows, deterministic 13Z NBM is coming
in already on the low side of the ensemble spread, generally in
the 25th-10th percentile so did not adjust suggested lows much in
this case, other than massaging traditionally cooler locations
across the Pascagoula and Pearl River drainage basins. Next, did
apply a noticeable target of opportunity to dewpoints both Monday
and Tuesday afternoons during peak diurnal mixing, as model
soundings illustrate a well-mixed PBL/adiabatic thermal profile to
1) support occasionally breezy winds and 2) likely mix down well
below suggested deterministic NBM guidance. Introduced a steady
transition to 25th to eventual 10th percentile dewpoints both
afternoons, bringing MinRH`s into the 30`s for most areas. This
will without a doubt make it feel much, much more comfortable both
days. As mentioned yesterday, something to remember is the sun
angle is still pretty high, and in the direct sunlight it`ll still
feel hot (and a much drier atmosphere will likely spike UV index
making for a risk for sunburn). Something to consider, otherwise
it`ll be a nice change in the hot summer we`ve been through so far
and a nice reminder that Fall is almost here! Beyond Tuesday into
the middle to later parts of the week, moisture steadily returns
back to the region underneath a building upper-level weakness
(broad SE US troughing pattern) that`ll bring back a few scattered
shower/storm chances. For now, best chances are looking across
the coastal areas of SE LA and MS, within greatest total column
moisture, but will monitor how far north moisture return builds to
support shower activity within this upper-level weakness with
time. Temperatures remain seasonal, with no excessive heat
concerns over the next 5-7 days. KLG
&&
.AVIATION...
(06Z TAFS)
Issued at 1153 PM CDT Sat Sep 6 2025
Drier air is being ushered in by light northerly flow behind a
weak frontal system, and VFR conditions will prevail through the
period. Only a slight chance for pop-up weak convection near HUM
on Sunday which does not warrant a PROB30 at this time.
&&
.MARINE...
Issued at 1153 PM CDT Sat Sep 6 2025
A cold front is expected to progress south across marine
waters through the morning on Sunday, introducing a steady wind
shift from the NNE to NE and drier air to progressively filter into
the region into the day on Sunday. Winds will be delayed to respond
increasing primarily 12-18kts for Gulf waters during the morning
thru afternoon hours on Sunday, with another reinforcing push of NE
winds expected overnight into early Monday. During this time period
(primarily 10PM thru 1PM Monday), winds may reach sustained upwards
of 15-20 knots, especially for outer Gulf zones south of the MS
sound including Chandeleur and Brenton sounds. A Small Craft
Advisory has been issued for these areas during this time frame.
Waves/seas will respond into the 3-5ft range generally before
abating Monday evening. Mid/late week, winds shift more easterly but
remain slightly elevated in the 10-15kt range, especially for
eastern zones which will keep waves/seas also slightly elevated in
the 2-4ft range for outer waters, 1-2ft for protected waters.
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB  87  66  84  60 /  30  10  10   0
BTR  91  69  88  64 /  20   0  10   0
ASD  90  69  88  62 /  20   0  10   0
MSY  92  76  90  71 /  20  10  10  10
GPT  90  70  90  65 /  20  10  10   0
PQL  92  69  90  63 /  20  10  10   0
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...Small Craft Advisory from 10 PM Sunday to 1 PM CDT Monday for
     GMZ536-538-555-557-575-577.
MS...None.
GM...Small Craft Advisory from 10 PM Sunday to 1 PM CDT Monday for
     GMZ538-555-557-575-577.
&&
$$
SHORT TERM...TJS
LONG TERM....KLG
AVIATION...TJS
MARINE...TJS

NWS LIX Office Area Forecast Discussion