149
FXUS64 KMOB 230954
AFDMOB

Area Forecast Discussion
National Weather Service Mobile AL
454 AM CDT Mon Sep 23 2024

...New NEAR TERM, SHORT TERM, LONG TERM, MARINE...

.NEAR TERM...
(Now through Tuesday night)
Issued at 454 AM CDT Mon Sep 23 2024

An upper ridge over much of the Gulf and adjacent northern Gulf
coast states is deflected out of the forecast area through Tuesday
in response to a longwave trof which evolves over the central states
and begins to advance into the eastern states. A surface ridge will
be oriented near/along the northern Gulf coast today and remains
close to this position into Tuesday, and this allows for a southerly
to southeasterly flow to become established over the forecast area
today and continue into Tuesday. Despite the movement of the upper
ridge, waning subsidence effects look sufficient to suppress
convective development, although can`t rule out a shower or storm
developing each afternoon. Highs today mostly range from 90 to 95,
then highs on Tuesday will be mostly in the lower 90s. Lows tonight
and Tuesday night range from around 70 inland to 70-75 near the
coast. A low risk of rip currents is expected through Tuesday night.
/29

&&

.SHORT TERM...
(Wednesday through Friday)
Issued at 454 AM CDT Mon Sep 23 2024

Overview... We continue to monitor an area of low pressure that is
beginning to show signs of development over the Western Caribbean.
This feature (which has recently been designated Invest 97L) is
currently a part of a larger scale Central American Gyre (CAG), and
will continue to organize over the next few days. This system now
has a 70 percent chance of developing into a tropical cyclone over
the next 48 hours and a 90 percent chance over the next 7 days. With
a trackable feature now in place, model guidance this morning is
slowly starting to become a little more aligned with regards to the
system`s overall trajectory. In addition, with the storm acquiring
an `invest` designation, high resolution hurricane-specific models
(HWRF, HMON, etc.) are now being utilized for this system to help
answer intensity-related questions. As is the case with the global
models, it should be stressed that any one particular run from these
models should not be taken at face value. That being said, it should
be noted that the full suite of these models are offering hints at a
rather quick intensification period as the storm begins its trek
into the Gulf. Due to continued uncertainties with the upper-level
steering patterns at play and how fast the system can intensify,
there is still a variety of solutions that are being presented
(giving way to a continued low confidence track and intensity
forecast) and additional changes will still be possible over the
next day or two. I will once again break down the remainder of the
discussion into a "what we know" section and a "what we don`t know
at this time" section.

What we know... As stated above, Invest 97L has formed just off the
coast of Nicaragua and Honduras. Although activity is still rather
disorganized, pockets of deep convection are continuing to bubble up
around the developing center of circulation. Environmental
conditions are certainly conducive for further development thanks to
the very warm water temperatures in that region and being located
underneath an upper-level anticyclone (which is giving way to low
wind shear). 97L will initially be steered north-northwestward
around the larger-scale CAG feature, crossing through the Yucatan
Channel and arriving in the southern Gulf by Wednesday. At this
point, the system will start to break off from the CAG and will
start feeling the steering effects of the upper-level features to
its north. The known steering features include: an upper ridge
located over the southeast US and a longwave trough digging into
the central US. With regards to the trough, almost all models over
the past 24 hours have aligned with the solution that suggested
that the upper trough will dig far enough south to break off from
the northern jet stream, resulting in an anomalously large upper
low that parks itself near the Mississippi River Valley. This will
help to break down the ridge and allow for 97L to lift northward
over the eastern Gulf. Although the exact path is still uncertain
at this time, guidance is coming into fairly good agreement that
97L`s eventual path will likely result in a landfall somewhere
along the Florida Panhandle/Big Bend area, and with the favorable
conditions in place, it is a good chance that it will make
landfall as a hurricane. A few additional things to keep note
of... 1) Models continue to suggest that this system will be quite
large, so even though the eventual track of this system is rather
murky, hazardous marine conditions, dangerous surf, and life
threatening rip currents will likely be felt across a majority of
the Gulf Coast region, regardless of track. 2) Once 97L gets
picked up by the upper low, it will move to the north very
quickly. While this is good news from an impacts standpoint (as
the storm is not going to linger around for multiple days), this
will leave very little time for preparations, especially if one is
waiting for the system to develop and acquire a name/cone/etc.
Although impacts from the system would not begin until Thursday,
numerous showers and storms are expected out ahead of the system
on Wednesday. Therefore, if you need to make any preparations, it
is recommended to take advantage of the dry days we have (today
and tomorrow) to do so.

What we don`t know at this time... Thankfully today we have more
answers than we did this time yesterday, although there are still a
lot of uncertainties when looking at the finer details. The first
question is, where exactly will the core of the storm go? As stated
earlier, models are beginning to focus in on a landfall somewhere
along the Florida Panhandle/Big Bend area. While most guidance
cluster it to the east of our area at this time, that is not to say
we are out of the woods. Expect models to continue shifting back and
forth over the next day or so as they continue to resolve the
placement of the upper cutoff low. A further west upper low will
result in a landfall closer to our area (more impacts for our CWA),
while a further east upper low pushes the landfall location closer
to the Big Bend area (less impacts for our CWA). At this time, we
just do not know exactly what will transpire and therefore, we
cannot, with confidence, hone in on specific impacts at this time.
But as stated before, even if the center does not directly strike
our CWA, impacts will likely be felt far removed from the center of
the system due to its expected size. Hopefully over the next 24 to
36 hours, we will be able to focus more on our local impacts.
The other question is how strong will the storm get? The answer
to that is still yet to be determined. For most of its journey
across the western Caribbean and eastern Gulf, signs are pointing
to a continued pattern that favors strengthening (high water
temps, low shear, and a rather moist environment). There could be
an increase in wind shear over the northern Gulf and a possibility
that some dry air may attempt to wrap into the system as it
becomes intertwined with the upper low, but overall, all signs
point to strengthening, potentially into a hurricane. With the
favorable conditions in place, cannot rule out a bout of rapid
intensification as it moves into the Gulf.

We will continue to monitor trends closely and we urge residents and
visitors across the entire central/eastern Gulf Coast to continue to
monitor the forecast, check their hurricane kits, and evaluate
and refresh any needed supplies. /96

&&

.LONG TERM...
(Friday night through Monday)
Issued at 454 AM CDT Mon Sep 23 2024

There is some uncertainty with the overall pattern early in the
period which depends on how an anticipated tropical system affects
the region. Please see the National Hurricane Center for more
information.  Otherwise, an upper low is expected to be centered
over Arkansas/Louisiana/Mississippi then slowly weakens and lifts
off into the interior eastern states through Monday. Have opted to
continue with a dry forecast for Friday night with deep layer dry
air anticipated to have moved into the area, then slight chance pops
follow for the eastern half of the area on Saturday as deep layer
moisture improves. Rain chances could end up being limited on Sunday
and Monday depending on how the pattern plays out, but for now have
gone with slight chance to chance pops and will reassess on later
shifts. /29

&&

.MARINE...
Issued at 454 AM CDT Mon Sep 23 2024

No impacts are expected through Wednesday afternoon other than
higher winds and seas near storms. For Wednesday night into
Thursday, a potential tropical system could bring significantly
higher seas and strengthening winds to the marine area. Please see
the National Hurricane Center for more information. Winds and seas
are expected to subside Thursday night into Friday night, although
there is uncertainty regarding how quickly this occurs. /29

&&

.PRELIMINARY POINT TEMPS/POPS...
Mobile      93  71  91  71  86  70  79  68 /   0   0  10  20  70  70  70  40
Pensacola   91  74  89  75  85  72  79  71 /   0   0  10  30  70  80  80  40
Destin      90  75  88  75  85  73  80  74 /   0   0  10  30  60  80  80  50
Evergreen   95  68  93  69  87  70  79  68 /   0   0  10  20  70  80  80  50
Waynesboro  93  69  92  69  87  67  80  67 /   0   0  10  20  60  50  60  40
Camden      93  70  92  69  85  68  77  67 /   0   0   0  30  70  70  70  50
Crestview   94  69  93  70  86  71  79  67 /   0   0  10  30  70  80  90  50

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...None.
FL...None.
MS...None.
GM...None.
&&

$$

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