Baton Rouge, Louisiana Weather Forecast Discussion

959
FXUS64 KLIX 240559
AFDLIX
Area Forecast Discussion
National Weather Service New Orleans LA
1259 AM CDT Wed Sep 24 2025
...New SHORT TERM, LONG TERM, AVIATION, MARINE...
.KEY MESSAGES...
 - Much-needed rain returns to the forecast ahead of a midweek
    cold front.
- Strong to a few severe storms possible this afternoon and this
   evening.
- Locally heavy rain possible this afternoon and this evening.
&&
.SHORT TERM...
(Today through Thursday)
Issued at 1257 AM CDT Wed Sep 24 2025
A good indicator about how favorable the next few days will finally
be for rain is seeing isolated showers continue to develop at 4
and 5z. There were a few storms in the inner waters east of the MS
Delta but we also had a one or two showers inland as well. On WV
there is some evidence of an area of lift stretching from
northeast to southwest from cntrl GA across SELa and into the
northwestern Gulf. It is subtle but can be seen. Combine that with
TPW values from GOES19 around 2-2.2" and even this subtle lift is
enough to continue to allow a few showers to develop through the
night tonight.
This already sort of sets the stage for this afternoon and this
evening. As mentioned in the "Key   Messages" strong and even one or
two severe storms are possible today but, in addition to that
locally heavy rain is likely. Synoptically a L/W trough is setting
up over the eastern half of the CONUS. The main closed low is
already moving south over WI with a highly positively tilted
trough axis back to the WSW moving through the 4 corners and central
Plains. This trough axis will slowly amplify as the main low begins
to open up over the Great Lakes and the trough axis starts to swing
through the MS Valley. This trough will not completely move through
the area until late Friday and even now the base of the trough may
eventually close and possibly cut off over the southeastern CONUS
this weekend. At the sfc a low currently over the Mid MS Valley will
continue to slide northeast towards the OH Valley and then into
southeastern Canada overnight Thursday night. This will drag a weak
cold front into the area with the cold front finally sliding into
the Gulf Friday morning. This will finally bring the best chance of
rain we have seen the entire month over the next 48 hours and some
of the rain could be locally heavy along with a few strong to maybe
even one or two severe storms.
From a standpoint of strong to severe. The old day 2 from SPC (the
new day one will be out shortly) had much of the area under a
Marginal Risk and that still seems appropriate. There isn`t any
strong well defined wave moving through but we will see mid lvl flow
gradually increase this afternoon and early evening. The longer
convection can hold off the warmer we will get today and the more
unstable we will get. In addition hghts will begin to slowly fall
and cool aloft and this will lead to slightly steeper mid lvl lapse
rates this afternoon and early evening. Combine that with PWs that
could range between 2.1 and 2.4" and it would take just about a
sneeze to get showers to develop. This afternoon we will see
increasing LL confluence especially across the northwestern half of
the CWA. At the same time we will be under a very favorable upper
level regime. The jet will be in place across the southern Plains
and then northeast into the Ohio Valley while an upper low will be
in place over the eastern Gulf. This places the area under very
efficient diffluence aloft. This could lead to a few storms
developing quickly this afternoon and with although nothing suggest
organized severe storms there will be enough forcing and ingredients
to get a few strong to severe storms capable of producing hail and
strong to damaging wind gusts.
The slightly more interesting impact is locally heavy rain. With the
amount of the moisture we will have in place combining with the very
impressive upper level diffluence storms will be very efficient rain
producers. If we see any storms that are slow moving or storms train
over an area those locations could quickly see 2 to 3 inches of rain
in a short time. The greatest risk for for locally heavy rain and
strong storms will be this afternoon and through the first half of
the evening. After that the potential for strong to severe storms
will begin to wane as we begin to lose the peak instability. Upper
lvl diffluence will also not be as strong heading into Thursday but
with the region still under the RRQ of the jet leading to enhanced
upper lvl divergence efficient rain producers will still be
possible.
Rain will likely continue throughout the night tonight slowly
becoming widespread Thursday early especially as the cold front
starts to slide into the region. However, there will be nothing
ere near the instability in place that we see today. Any strong
storm we see will be driven by the increase in the LL and mid level
flow and stronger forcing. PWs will still be at the very upper end
of the climate record so again it will not take a lot of forcing to
get showers and some embedded thunderstorms. This will also continue
to lead to efficient rain. /CAB/
&&
.LONG TERM...
(Thursday night through Tuesday)
Issued at 1257 AM CDT Wed Sep 24 2025
We get another slight taste of Fall going into the weekend but
nothing too impressive yet. Models continue to be in decent
agreement through the weekend and into the beginning of next week
even though the mid lvl pattern gets as chaotic as it looks like
it will be.
As mentioned earlier the base of the trough that is moving through
the area will finally get east of us late Friday before it starts to
close off over the southeastern CONUS and then Saturday night/Sunday
it will become cutoff. The ridge over the Plains this weekend will
slide east over top of the cutoff low merging with a ridge over the
Atlantic and likely north of possible tropical systems in the
Atlantic. By early next week we could see a Rex block setup over the
eastern CONUS. The cutoff low will drift north towards the TN Valley
while a ridge become centered over the Great Lakes and stretches
north into central Canada. We will see some broad ridging over the
Gulf and into the Lower MS Valley. That will probably lead to the
region warming back up. /CAB/
&&
.AVIATION...
(06Z TAFS)
Issued at 1257 AM CDT Wed Sep 24 2025
VFR conditions currently impact all terminals and will probably
continue through the morning before convection starts to develop
across the northwest. Convection will impact all terminals in the
next 24 to 36 hours beginning with BTR and MCB midday early
afternoon and then extending southeast through the late afternoon
and evening. GPT will be the last terminal to see impacts. TSRA is
in every TAF and with any storm expect cigs and vsbys to drop into
MVFR and IFR at times. /CAB/
&&
.MARINE...
Issued at 1257 AM CDT Wed Sep 24 2025
Surface high pressure continues to dominate the Gulf but a cold
front is on the way. Just before midnight the cold front was moving
into the ARKLATEX and central TX and will slowly continue to work
southeast over the next 3 days. The front will approach the coastal
waters overnight Thursday night and into the coastal waters late
Friday morning. Light onshore flow will continue through today but
winds will become more chaotic as storms begin to move into the
coastal waters ahead of the front overnight tonight and through the
day Thursday. Once the front finally moves completely through the
coastal waters late Friday light offshore flow will develop
temporarily. /CAB/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB  88  69  84  64 /  60  70  60  20
BTR  90  72  83  66 /  60  70  60  20
ASD  90  71  84  66 /  40  50  80  40
MSY  92  76  86  72 /  40  50  80  40
GPT  89  74  85  69 /  30  50  80  50
PQL  90  72  86  67 /  20  50  90  60
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...None.
GM...None.
MS...None.
GM...None.
&&
$$
SHORT TERM...CAB
LONG TERM....CAB
AVIATION...CAB
MARINE...CAB

NWS LIX Office Area Forecast Discussion