703
FXUS64 KMOB 251801
AFDMOB

Area Forecast Discussion
National Weather Service Mobile AL
100 PM CDT Wed Sep 25 2024

...New AVIATION...

.AVIATION...
(18Z TAFS)
Issued at 100 PM CDT Wed Sep 25 2024

Scattered showers and a few thunderstorms have developed over
eastern and central portions of the area this afternoon.
Additional showers and storms are anticipated overnight and into
Thursday morning with the highest coverage generally occurring
along and east of I-65. Local reductions to MVFR and IFR
conditions will be possible around this activity. More widespread
reductions will likely begin to move into the area from the east
Thursday morning as a low level cloud deck spreads across the
region. Light north to northeasterly winds continue tonight
before increasing through Thursday morning. /14


&&

.NEAR TERM...
(Now through Thursday)
Issued at 100 PM CDT Wed Sep 25 2024

An upper level longwave trough, currently located over the
central US is continuing to dig southeastward this morning. Within
the next few hours, it will begin to break off from the northern
just stream, resulting in an anomalously large upper low that
parks itself over the Mississippi River Valley. This low is
responsible for two things: 1) helping to send a frontal boundary
into the region from the west, and more importantly 2) keeping the
core of soon-to-be Hurricane Helene to our east.

For today, the front, which is currently located over central
Mississippi, will begin moving into our local area. Plenty of
forcing due to strong diffluence aloft and convergence along the
front, in addition to ample moisture (PWATs around 1.6 to 1.9
inches), will result in scattered to numerous showers and storms
across the area, especially in the afternoon. The front should
stall somewhere near the I-65 corridor by Wednesday evening,
allowing for high rain chances to continue (especially along and
east of it) through Wednesday night. Although lapse rates are
rather poor, daytime heating should allow for some destabilization
to occur. This, paired with favorable deep layer shear due to the
close proximity of the upper low could result in the organization
of a few strong to marginally severe storms. Gusty to damaging
winds seem to the primary threat. Not really anticipating a
tornado threat due to very weak low-level shear values and
straight-lined hodographs.

For Thursday, all eyes point to the Gulf as Helene rapidly
strengthens into a major hurricane and sprints toward the Florida
Big Bend area. Thankfully for our local area, the core is far
enough away for us to be spared from the hurricane force winds and
storm surge effects. However, as this system quickly lifts
northward, it is expected to grow in size considerably and
therefore we will still see some impacts. Hazardous marine
conditions (due to strong winds and high waves), dangerously high
surf (breakers greater than 10 feet), and life threatening rip
currents are expected, especially as we get into the Thursday
afternoon through Thursday night timeframe. We will also be
monitoring for the potential of, at least, minor coastal flooding
along the coastal interface going into Thursday night. As far as
rainfall, we are currently anticipating a general 2 to 4 inches
(locally higher possible) over south central Alabama and the
western Florida Panhandle through this entire period, with lower
amounts for southwest Alabama and southeast Mississippi. This
rainfall could lead to isolated to scattered instances of flash
flooding, especially over urban and poor drainage areas, and some
minor river flooding cannot be ruled out. And lastly, wind gusts
of around 25 to 35 mph are anticipated across the area (highest
near the coast) starting as early as Thursday morning. An
occasional gust to near tropical storm force cannot be ruled out.
We will continue to monitor the progress of Helene closely, as any
shifts to the west will likely bring stronger impacts than what
was listed above. /96

SHORT AND EXTENDED TERM...
(Friday through Tuesday)
Issued at 354 AM CDT Wed Sep 25 2024

Per the latest track for Helene from the National Hurricane
Center, the system is expected to have weakened to a depression
over northern Georgia by Friday morning. The system becomes
absorbed into a rather unusual large upper low which slowly moves
from over the lower Mississippi River valley to become centered
near the Mississippi/Ohio River confluence by Saturday. The upper
low later breaks down leaving an upper trof over the eastern
states by Monday. Am anticipating predominately dry conditions for
our area on Friday, with dry conditions prevailing through
Sunday. There appears to be a small chance for rain over the
eastern half of the area on Monday although confidence is low,
then dry conditions prevail on Tuesday except for a possible small
chance for rain over Okaloosa county Florida. A high risk of rip
currents will continue through Friday night, then a moderate risk
is expected on Saturday with a low risk for Sunday. A high surf
advisory will probably be necessary for Friday, but surf
conditions will have subsided by Friday night. /29



&&

.PRELIMINARY POINT TEMPS/POPS...
Mobile      69  81  64  83  66  86  66  87 /  50  40  20  10   0   0   0  10
Pensacola   73  80  68  82  72  85  72  85 /  80  70  30  10   0   0   0  10
Destin      74  81  71  82  73  85  73  85 /  80  80  50  10   0   0  10  10
Evergreen   70  78  64  83  62  86  64  86 /  70  70  50  10   0   0   0  10
Waynesboro  65  82  62  81  62  84  61  85 /  30  30  20  10   0   0   0  10
Camden      68  77  63  80  62  83  62  83 /  60  60  50  10   0   0   0  10
Crestview   72  79  66  83  64  86  66  86 /  80  80  50  10   0  10   0  10

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...High Rip Current Risk from 9 PM CDT this evening through late
     Friday night for ALZ265-266.

     High Surf Warning from 6 AM Thursday to noon CDT Friday for
     ALZ265-266.

FL...High Rip Current Risk from 9 PM CDT this evening through late
     Friday night for FLZ202-204-206.

     High Surf Warning from 6 AM Thursday to noon CDT Friday for
     FLZ202-204-206.

     Wind Advisory from noon Thursday to 6 AM CDT Friday for FLZ204-
     206.

MS...None.
GM...Small Craft Advisory from 4 AM Thursday to 1 PM CDT Friday for
     GMZ630>635-650.

     Tropical Storm Warning for GMZ636-655-670-675.

&&

$$

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