Zachary, Louisianna 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

150
FXUS64 KLIX 040535
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1135 PM CST Tue Dec 3 2024

...New AVIATION...

.SHORT TERM...
(This evening through Thursday night)
Issued at 255 PM CST Tue Dec 3 2024

A fast moving southern stream upper level vorticity max sliding
through the area tomorrow and Thursday will be the main feature
influencing the forecast through the short term period. In advance
of this upper level impulse, increasing southerly flow in the low
to mid levels will help to transport deeper Gulf moisture back
into the area. This is best reflected by PWATS rising from around
half an inch tonight to between 1.5 and 1.75 inches by late
Wednesday night and Thursday morning. These values are around the
90th percentile for this time of year. Fortunately, the rainfall
is expected to remain light to moderate and occur over an extended
period of time. This will limit the flood threat greatly even as
storm total precipitation approaches 2 inches in a few locations.

The southerly flow pattern will also lead to a quick warm up over
the next 24 hours. Lows tonight will once again be chilly with
lows falling into the lower to middle 30s along and north of the
10/12 corridor and the low to mid 40s further to the south. Highs
will quickly rise into the 60s tomorrow afternoon, and overnight
lows will only dip into the 50s tomorrow night. Thursday will see
highs warm back into the 60s, but a cold front sweeping in from
the north as the upper level vort max shifts to the east and a
northern stream trough deepens over the eastern CONUS will quickly
usher in a much colder and drier airmass by Thursday night. Lows
will dive into the lower to middle 30s again for locations along
and north of I-10/12, and the upper 30s and lower 40s further to
the south. Fortunately, very dry air will also move into the area
Thursday night and this will push PWATS down to around 0.50 to
0.75 inches or close to seasonal averages by late Thursday night.
The end result is that precip chances will not align with the
freezing temperatures over the northern third of the CWA as the
deeper moisture is pushed back offshore. Overall, there is still a
good deal of spread between various model solutions on the
strength of the cold pool advecting into the area Thursday night.
Have opted to trend a bit cooler than the NBM, and more toward the
ECMWF solution as a strong and deep cold pool over the northern
Plains and Canada remains in place.

&&

.LONG TERM...
(Friday through Monday night)
Issued at 255 PM CST Tue Dec 3 2024

Continuing the trend of leaning more toward the ECMWF solution on
Friday will lead to daytime highs running a few degrees cooler
than the NBM with highs only warming into the lower 50s forecast
for the entire region. This may even be too warm as the ECMWF
keeps readings into the upper 40s. Friday night will also be very
cold as a surface high becomes a bit more centered over the region
resulting in lighter winds. Lows will easily fall back to the same
levels seen the night before. Fortunately, conditions will remain
dry through this period as PWATS linger around 0.75 inches.

Temperatures will begin to modify over the weekend as high
pressure shifts to the east and a potent southern stream trough
moves into the southern Plains. Increasing deep layer southerly
flow will once again usher in a warmer and more moist airmass with
PWATS increasing to between the 75th and 90th percentile
climatologically for this time of year, and temperatures warming
into the lower 70s by Sunday afternoon. These above average
conditions will continue into Monday and Monday night as deep
layer southerly flow persists. The approaching southern stream
trough axis and more favorable jet dynamics will induce a broad
region of increasing upper level lift, and this lift will tap into
a modest amount of instability to produce periods of rain with
embedded thunderstorm activity. This is reflected by likely PoP
forecast for Sunday night and Monday as the trough axis begins to
move into the area. Sounding profiles are not very supportive of
severe storms at this time for early next week, but this will
continue to be monitored as the evolution of the southern stream
trough comes into better focus.

&&

.AVIATION...
(06Z TAFS)
Issued at 1131 PM CST Tue Dec 3 2024

VFR conditions with light/variable winds expected to persist
through the next 12 hours. Mid level clouds will be moving in
from the west before noon. As the day progress, light to
occasionally moderate rain will spread east across Louisiana and
Mississippi.

&&

.MARINE...
Issued at 255 PM CST Tue Dec 3 2024

Continued cold air advection over the waters tonight will keep
winds elevated for the waters west of the Mississippi River
through the overnight hours. These stronger offshore winds of 15
to 20 knots will keep exercise caution wording in the forecast. By
tomorrow, a surface high pressure system will become more
centered over the area, and this will allow winds and seas to fall
below headline levels from tomorrow through Thursday afternoon.
However, another strong cold front will sweep through the waters
Thursday night in the wake of a passing low, and winds will rise
back into advisory levels from late Thursday night through Friday
night. As another high moves through the Deep South on Saturday
and Sunday, winds will turn more easterly and also fall into the
10 to 15 knot range. Seas will also ease from 5 to 7 feet offshore
Saturday morning to to 3 to 5 feet by Sunday.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  32  63  52  59 /   0  50 100  70
BTR  39  67  56  63 /   0  50  90  70
ASD  35  67  56  65 /   0  20  80  80
MSY  46  68  60  66 /   0  20  70  80
GPT  38  66  57  66 /   0  10  70  70
PQL  32  66  55  66 /   0   0  60  80

&&

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

$$

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