Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

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481
FXUS64 KLIX 150555
AFDLIX

Area Forecast Discussion
National Weather Service New Orleans LA
1255 AM CDT Tue Jul 15 2025

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

.SHORT TERM...
(Today through Wednesday)
Issued at 1241 AM CDT Tue Jul 15 2025

All the impacts aren`t just in the long term as we will see some
impacts today from a standpoint of heat but that is possibly
marginal if convection is a able to over perform a little today.
Convection did fire quickly again yesterday and kept most of the
area just below adv criteria but that doesn`t quite appear to be
the case today.

As for the next two days before we start to see possible more
significant impacts. The ridge aloft will dominate the region today
and it looks like it will be just strong enough to suppress
convection much longer during the day than the previous days and
this would allow the region to warm just a little more and with
abundant boundary layer moisture in place it will be a little easier
to get heat indices of 105 to 110. With that a Heat Advisory was
already issued for tomorrow and includes much of the area.

Wednesday is a little more of a question mark as it could be another
hot day. A lot will depend on the speed of our system moving through
the Gulf. If convection moves in faster from the east then much of
the area likely stays below heat advisory criteria but northwestern
sections of the CWA could still need a heat advisory. That said we
continue to mix out rather well and may be just below heat advisory
criteria even in the northwestern zones that have the lowest rain
potential. /CAB/

&&

.LONG TERM...
(Wednesday night through Monday)
Issued at 1241 AM CDT Tue Jul 15 2025

Focus is obviously on the system that is currently just east of
the Florida peninsula. NHC increased the odds of this developing
into a tropical depression over the next 7 days to 40%. Models are
still all over the place with how much this may develop but
overall there is rather strong continuity with many of the medium
and now tropical specific models in some semblance of a system
moving into the north-central Gulf coast region. This would bring
about some hazardous marine conditions, some mild coastal
flooding, but the greatest concern appears to be very heavy
rainfall. How much and how long the rain sticks around is unknown
and likely won`t be known until it is just about to start. That
said the potential is there for a concern 36 to 48 hours and
hopefully not longer.

Things could begin as early as Wednesday night but once the rain
does start we may be in a prolonged period of rain with numerous to
widespread showers and embedded thunderstorms lasting through
Friday. As mentioned earlier there is already a trough of low
pressure east of the FL peninsula and it is showing some slow
organization both on radar and satellite. This system is expected to
move across FL tomorrow and into the eastern Gulf overnight Tuesday
night. As this system moves west across the northeastern and north-
central Gulf if it is able to stay offshore it will have time and
slightly favorable environmental conditions to organize and could
eventually become a tropical cyclone. The upper lvl environment will
be conducive with decent outflow on the west/southwest side of it
and a favorable outflow setup to the north/northwest. This is not
just a problem from tropical development standpoint as this is also
a problem Thursday through Friday with respect to rain. This system
will be accompanied by very rich moisture with PWs well abv 2" if
not abv 2.25" for a substantial time. Combine that with very good
diffluence aloft likely over an area of enhanced LL convergence and
the recipe is there for very efficient rain.

A key to focusing on what area could see the heaviest rain will
be the track, again the biggest determining factor with the heavy
rain will be the track. Does it move faster or slower west; how
far south does the system get after it leave FL; where does it
start to slow down and try to pivot/turn north. This will have
significant implications on where the heaviest rain falls.
Immediately to the northwest of it will possibly be the first
bout of moderate to heavy rain but the heaviest will most likely
be to the south and southeast of the eventual track and especially
as it starts to pivot/turn north. This will be the area with the
strongest LL convergence with a band or two developing. After
Friday night there is no strong feeling of where the remnants of
this system will be or where it will go. It could continue to
slide north and then around the southeastern CONUS ridge this
weekend and into next week or it could get trapped with locally
heavy rain still possible across the Lower MS Valley through the
weekend and maybe even into the new work week. That said this is
not an absolute and still a lot of unknowns at this time. If this
system remains a tad farther south moving right along the coast,
which would be the best case for our area, the heaviest rain will
then remain out over the coastal waters.

Given the possibilities of significant impacts due to heavy rain we
continue to bump up the forecast but again with the environmental
conditions we could see the current forecast is still likely
underdone. Widespread 2 to 5 inches of rain with locally higher
amounts possibly even exceeding 10 inches are not out of the
question. And that could just be through Friday night. At this time
flood watches look likely and may be issued as early as overnight
tonight (Tuesday night).

Continue to pay attention to the latest forecast and updates for the
back half of the work week. Double check your supplies and know what
to do and where to go in case flash flooding could impact you. If you
live right along any of the more quick responding rivers in the area
keep a very close eye on the river forecast over the next few days
from the Lower MS River Forecast Center. /CAB/

&&

.AVIATION...
(06Z TAFS)
Issued at 1241 AM CDT Tue Jul 15 2025

Overall all terminals are in VFR and will likely remain that way
through today. There will likely be isoalted to widely scattered
convection this afternoon and the most likely locations mya be
right along the southside of the lake impacting MSY and NEW
however confidence is low. /CAB/

&&

.MARINE...
Issued at 1241 AM CDT Tue Jul 15 2025

About another 36 to 48 hours of relatively benign conditions
across the coastal waters with high pressure sliding west across
the Gulf. Light winds and low seas will continue through Wednesday
but heading into Wednesday night winds will begin to slowly
increase in response to the disturbance moving west across the
northern Gulf. Whether or not this become a tropical system won`t
matter as conditions will become more hazardous Thursday and
through Friday. At the very least SCY headlines will be needed and
hopefully that is all. /CAB/

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  94  74  95  74 /  20  10  40  40
BTR  94  76  95  76 /  20  10  40  40
ASD  94  75  93  73 /  20  10  60  70
MSY  94  79  94  78 /  30  10  60  80
GPT  95  77  95  75 /  20  20  70  70
PQL  96  75  94  74 /  20  30  80  70

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...Heat Advisory from 10 AM this morning to 7 PM CDT this evening
     for LAZ034>037-039-046>048-056>060-064-065-070-071-076>090.

GM...None.
MS...Heat Advisory from 10 AM this morning to 7 PM CDT this evening
     for MSZ068>071-077-083>088.

GM...None.
&&

$$

SHORT TERM...CAB
LONG TERM....CAB
AVIATION...CAB
MARINE...CAB