McComb, Mississippi 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

309
FXUS64 KLIX 101743
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1243 PM CDT Thu Jul 10 2025

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

.SHORT TERM...
(This afternoon through Friday night)
Issued at 1043 AM CDT Thu Jul 10 2025

Not much to say that hasn`t already been said over the last few
days... Typical summertime weather will persist as the local area
remains situated between two upper level highs and under the
influence of weak troughing aloft.

Diurnally forced showers and storms are already affecting portions
of the area and scattered to locally numerous showers and storms
will continue through the afternoon hours, diminishing during the
early evening as we lose daytime heating. Tomorrow should see a
near repeat, but with potential for slightly less coverage as the
troughing aloft begins to flatten.

Temperatures will be near to slightly above normal with afternoon
highs in the low to mid 90s and morning lows in the mid to upper
70s.

&&

.LONG TERM...
(Saturday through Wednesday)
Issued at 1043 AM CDT Thu Jul 10 2025

Going into the weekend, we`ll start to see a pattern shift as the
main upper trough lifts northeastward and high pressure currently
over the western Atlantic builds westward toward the lower
Mississippi Valley. This will lead to a decrease in daily
convective coverage and an associated increased in afternoon
temperatures and heat index values.

Taking a deeper dive into the data, despite the high building into
the local area, we remain mostly on the periphery, so subsidence
aloft doesn`t appear strong enough at this time to completely shut
off diurnal convection. With onshore flow continuing to pump Gulf
moisture into the area, precipitable water values look to remain
near or even slightly above normal for this time of year. That
being said, we should still see some scattered afternoon showers
and storms. However, in areas that do not receive the benefit of
rain-cooled outflow, temperatures will be able to rise into the
mid to upper 90s. These temperatures combined with dewpoints in
the mid or even upper 70s will make for at least localized
oppressive conditions. The current forecast indicates heat index
values will reach heat advisory criteria (heat index of 108
degrees or higher) in some areas by Sunday or Monday, with at
least some potential for values near heat warning criteria (heat
index of 113 degrees or higher) Tuesday and Wednesday. This is
all dependent on exactly where and when showers and storms develop
across the region.

NBM seems to have a continued high bias in the forecast POPs
during the latter part of the forecast period. As mentioned above,
we should see at least some decrease in afternoon showers and
storms as the high builds in, so have adjusted the pops down
10-20% in some areas mainly in the Tues/Wed time frame to cap
them around 50%. Messaging wise it`s not a huge difference, but
it does take the coverage down from numerous to scattered. Further
downward adjustments may still be needed given that even 50% is
near or above the 90th percentile members in the ECMWF ensemble
guidance, but at least wanted to start showing a possible trend.

&&

.AVIATION...
(18Z TAFS)
Issued at 1043 AM CDT Thu Jul 10 2025

Outside of convection, VFR conditions will prevail through
the period. Today and tomorrow should continue to see a typical
summertime pattern with scattered to locally numerous showers and
storms mainly during the afternoon hours, calling for PROB30 or
TEMPO groups at all terminals. Convection should wane around 00z,
with benign conditions overnight.

&&

.MARINE...
Issued at 1043 AM CDT Thu Jul 10 2025

Marine conditions will be benign through the period outside of any
localized impacts from convection. In response to a broad ridge
over the Gulf, winds will generally be out of the south/southwest
at 10 kts or less aside from areas near the immediate coastline
where sea/lake/land breeze cycles will have an influence on both
direction and speed. Otherwise, a fairly typical summertime
convective pattern will persist with showers and storms developing
during the late night, peaking during the morning hours, and
diminishing through the afternoon and evening.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  71  91  72  93 /  20  80  40  50
BTR  75  92  74  93 /  20  80  40  60
ASD  74  92  74  93 /  20  80  50  50
MSY  77  92  78  94 /  20  80  40  60
GPT  75  91  76  92 /  40  80  50  50
PQL  74  91  74  92 /  40  80  50  50

&&

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

$$

SHORT TERM...DM
LONG TERM....DM
AVIATION...DM
MARINE...DM