707
FXUS64 KMOB 252117
AFDMOB

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

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

.NEAR TERM...
(Now through Thursday)
Issued at 417 PM CDT Wed Sep 25 2024

Water vapor imagery this afternoon shows an upper level low near the
borders of Kansas/Arkansas/Tennessee/Kentucky. This upper low will
continue to linger over the Middle Mississippi Valley through
Thursday before eventually diving into the Deep South late Thursday
night and early Friday morning. The progression of this upper low
will steer Hurricane Helene into the Big Bend region of Florida as a
major hurricane Thursday evening before they phase into one large
upper level feature over the Southeast on Friday.

Down in the lower levels, a subtle surface boundary is currently
draped across southwest Alabama and southeast Mississippi. This
front will continue to move through western portions of the area
through this afternoon before stalling along the I-65 corridor this
evening. Drier air is expected to filter into southeast Mississippi
and portions of southwest Alabama behind the front with PWATs likely
falling to around 1.25-1.5 inches tonight. This should help to keep
mostly dry conditions in place overnight and into Thursday for these
areas. Along and east of the surface front, there will be better
deep layer moisture in place as Hurricane Helene lifts northward
across the eastern Gulf. PWATs over south central Alabama, portions
of southwest Alabama, and the northwest Florida Panhandle will range
from 1.5 to 2.3 inches through Thursday. This moisture combined with
the weak surface boundary may help to keep a few lingering showers
and storms overnight in areas along and east of I-65. Rain chances
will begin to increase again on Thursday morning in these same areas
as peripheral bands from Helene move inland. With a rather tight
moisture gradient in place across the area, we expect numerous to
widespread showers in storms to move inland across the eastern half
of the area with isolated to scattered showers and storms possible
across far southwest Alabama. We will need to monitor the activity
on Thursday as these showers and storms will be efficient rainfall
producers which could lead to localized flood concerns especially in
areas where storms repeatedly move over the same areas. Rainfall
amounts of 2-4 inches are anticipated across south central Alabama
and northwest Florida, with locally higher totals possible.

In addition to the rainfall, we will also see wind and beach hazards
across parts of the area given the large extent of Hurricane Helene.
We`ll go into more detail on each of these hazards below.

.Wind Advisory. Winds will begin to increase as Helene approaches
the northeastern Gulf Coast.

.Beach Hazards: Long period swell packets will approach our entire
coastline late tonight and hit the beaches early Thursday morning.
Therefore, a High Surf Warning is now in effect from 6 AM Thursday
to noon CDT Friday for all our surf zones where large breaking waves
of 6 to 10 feet are expected. Wave runup should also result in water
levels of 1 to 2 feet above normally dry ground. If higher values
are expected, we may need to issue a Coastal Flood Advisory.
However, northerly winds will help to negate any impacts for our
bays, with the impacts mainly occurring along the immediate coastal
sections due to the wave runup. In addition, a High Rip Current Risk
remains in effect from 9 PM CDT this evening through late Friday
night. Everyone should remain out of the water due to life-
threatening surf conditions. Stay off of jetties, piers, and other
waterside infrastructure.

For Thursday night, conditions will quickly dry out from the
southwest to northeast as Hurricane Helene lifts across Georgia and
much drier air filters into the region. Temperatures Thursday night
will be rather pleasant with lows falling into the lower 60s inland
with middle and upper 60s further south. /14

&&

SHORT AND EXTENDED TERM...
(Friday through Wednesday)
Issued at 417 PM CDT Wed Sep 25 2024

The upper level low gradually weakens and lifts northeast into the
Ohio Valley by early next week. A dry airmass remains through much
of the area with only very isolated showers possible over the
weekend. A reinforcing shot of drier air is possible late in the
period. Highs will be in the low to mid 80s inland to mid and
upper 90s near the coast. /13

&&

.MARINE...
Issued at 417 PM CDT Wed Sep 25 2024

Tropical Storm Helene is expected to strengthen to near
hurricane strength when it reaches the northwestern Caribbean
Wednesday morning. Further intensification is expected and this
system is likely to become a major hurricane before approaching the
northeastern Gulf Coast Thursday evening. Significantly higher seas
and strengthening winds are expected over the marine area as a
result. A Tropical Storm Watch has been issued for the Florida 0-60
nm Gulf waters. We may need to include a Small Craft Advisory for
the remainder of the marine area beginning late Wednesday night
which continues until seas subside Friday morning. Please see the
National Hurricane Center for additional information. Winds and seas
are expected to gradually subside Friday into Friday night with a
moderate westerly to southwesterly flow prevailing through the
weekend. /14



&&

.PRELIMINARY POINT TEMPS/POPS...
Mobile      70  83  65  83  65  87  63  87 /  30  30  10  10   0   0   0   0
Pensacola   72  79  69  82  70  85  70  86 /  70  70  30  10   0   0   0  10
Destin      73  80  70  83  73  85  71  85 /  80  80  50  10   0   0   0  10
Evergreen   68  80  63  83  63  85  61  86 /  60  80  50  10   0   0   0  10
Waynesboro  65  82  62  81  62  84  61  84 /  20  20  10  10  10   0   0   0
Camden      66  76  62  79  63  82  60  82 /  40  60  40  20   0   0   0   0
Crestview   70  78  64  84  64  86  64  87 /  80  80  50  10   0  10   0  10

&&

.MOB WATCHES/WARNINGS/ADVISORIES...
AL...Wind Advisory from noon Thursday to midnight CDT Thursday night
     for ALZ060-263>266.

     Coastal Flood Advisory from 6 AM Thursday to 1 PM CDT Friday for
     ALZ263>266.

     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 1 PM CDT Friday for
     ALZ265-266.

FL...Wind Advisory from noon Thursday to midnight CDT Thursday night
     for FLZ201>206.

     Coastal Flood Advisory from 6 AM Thursday to 1 PM CDT Friday for
     FLZ202-204-206.

     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 1 PM CDT Friday for
     FLZ202-204-206.

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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