908
FXUS64 KLIX 200847
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
347 AM CDT Thu Mar 20 2025

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

.SHORT TERM...
(Today through Saturday Night)
Issued at 306 AM CDT Thu Mar 20 2025

A very dry ridge of high pressure will build into the area today
in the wake of a cold front that swept through during the
overnight hours. A strong 925mb thermal trough axis will also
move through the area today into tonight resulting in below
average temperatures. Highs will struggle to reach into the mid
60s this afternoon and lows will plunge into the 30s and 40s
tonight. In fact, some patchy frost is expected to develop late
tonight into early tomorrow morning in the more protected
drainages of the Pearl and Pascagoula River basins. Beyond the
cold temperatures, the dry air will combine with gusty northwest
winds of 15 to 20 mph this afternoon to produce a brief period of
critical fire weather conditions this afternoon as relative
humidity values fall to near 20 percent. A Red Flag Warning is in
effect due to this increased fire risk today. The wind field will
collapse tonight as the surface high becomes centered directly
over the region.

This strong surface high will be the dominant feature influencing
the forecast through Friday night resulting in continued clear
skies, low humidity, and cooler than average temperatures. Highs
will modify slightly tomorrow as the heart of the 925mb thermal
trough axis shifts to the east, but highs will only warm to near
70 degrees or around 5 degrees below average. Given the dry air
and clear skies in place, a larger than average diurnal range will
occur, and this will support lows falling into the 40s and lower
50s Friday night.

Saturday into Saturday night will see an increased low level
return flow from the Gulf develop, but very dry air will continue
to persist in the mid and upper levels. This very well evidenced
by a strong capping inversion around 800mb that is consistently
shown in all of the model sounding guidance. With this dry air
lingering, only some suppressed strato-cumulus development is
expected Saturday afternoon as temperatures warm into the mid to
upper 70s. The increased low level moisture will allow overnight
lows to remain warmer than average Saturday night with readings
only dipping into the upper 50s and lower 60s. At this time, it
looks like a low overcast stratus deck will form beneath an
elevated inversion, but winds should remain strong enough to keep
fog formation at bay Saturday night.

&&

.LONG TERM...
(Sunday through Wednesday)
Issued at 306 AM CDT Thu Mar 20 2025

Sunday and Monday will be the most active period of weather in the
entire forecast as a broad and deep longwave trough axis passes
through the area. An attendant cold front will accompany this
trough axis is passes through. Ample deep layer forcing along the
front and trough axis will tap into moderately moist conditions as
PWATS rise to around 1.25 inches by Sunday night to produce a band
of rain. This rain will pass through the area mainly from late
Sunday night into Monday morning before clearing the area by
Monday afternoon. A review of model soundings indicates that
instability parameters will very limited, and this should suppress
the overall thunderstorm threat as deep and sustained updrafts
will be harder to maintain. That doesn`t mean that thunderstorms
won`t happen, but the expectation is that they will be more
isolated to widely scattered than the surface based temperatures
near 80 and dewpoints in the 60s would suggest. This lack of
instability is entirely driven by weaker lapse rates in the 850 to
700mb range. Shear will also be limited with effective bulk shear
generally between 30 and 40 knots. Overall, the severe potential
for our area Sunday night into Monday morning is very low based
the latest guidance.

After the front and and parent trough axis sweep through the area
Monday night, another dry and stable ridge of high pressure will
build over the area and remain in place through Wednesday. The
airmass building in behind the front will not cool much and in
fact should be more Pacific based in origin. This will allow
temperatures to remain near average on Monday with highs warming
into the lower 70s and lows only dipping into the upper 40s and
lower 50s. By Tuesday and Wednesday, the surface high will shift
to the east allowing for warmer air and moisture to begin
advecting back into the area. Aloft, a very strong mid to upper
level ridge will also be building in, and the increase in deep
layer subsidence will support significant warming. Highs will
quickly climb to near 80 degrees on Tuesday and Wednesday, and
that is on the conservative end by Wednesday as NBM guidance
indicates a 70 percent chance of temperatures climbing above 80
degrees.  PG

&&

.AVIATION...
(06Z TAFS)
Issued at 306 AM CDT Thu Mar 20 2025

A very dry airmass will advect into the area allowing for
prevailing VFR conditions at all of the terminals today into
tonight. Winds will be gusty from the northwest at all of the
terminals with gusts of 15 to 20 knots expected through at least
00z.

&&

.MARINE...
Issued at 306 AM CDT Thu Mar 20 2025

A brief period of very strong winds will develop today in the wake
of a passing front with gusts approaching gale for a few hours in
the western waters this morning. As a result, small craft
advisories in place for all of the waters through this evening.
Winds will quickly drop off tonight as a surface high builds over
the area and these lighter winds will persist through Saturday.
Southerly winds will increase back to around 15 knots Saturday
night and remain that way through Sunday in advance of an
approaching front, but small craft advisories are not anticipated.
In the wake of the system, a lack of cold air advection will keep
winds in the 10 to 15 knot range for next Monday and Tuesday. So,
overall conditions will be fairly decent for maritime operations
once we get beyond today.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  62  35  70  43 /   0   0   0   0
BTR  63  37  71  46 /   0   0   0   0
ASD  65  36  69  46 /   0   0   0   0
MSY  64  45  69  51 /   0   0   0   0
GPT  65  38  65  49 /   0   0   0   0
PQL  65  34  66  44 /   0   0   0   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Red Flag Warning from 9 AM this morning to 7 PM CDT this evening
     for LAZ034>037-039-046>048-056>060-065-071-076-079>086.

GM...Small Craft Advisory until 7 PM CDT this evening for GMZ530-532-
     534-536-538-550-552-555-557-570-572-575-577.

MS...Red Flag Warning from 9 AM this morning to 7 PM CDT this evening
     for MSZ068>071-077-080>082.

GM...Small Craft Advisory until 7 PM CDT this evening for GMZ532-534-
     536-538-550-552-555-557-570-572-575-577.

&&

$$

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