179
FXUS62 KTAE 151429
AFDTAE

Area Forecast Discussion
National Weather Service Tallahassee FL
1029 AM EDT Sun Sep 15 2024

...New UPDATE...

.UPDATE...
Issued at 1026 AM EDT Sun Sep 15 2024

The PoPs were nudged downward across the region today as northeast
flow from a disturbance off the southeast coast keeps the best instability
mostly offshore. This is currently supported by radar and
satellite trends, along with the latest hi-res guidance.
Otherwise, the rest of the forecast looks to be on track.

&&

.NEAR TERM...
(Today and tonight)
Issued at 308 AM EDT Sun Sep 15 2024

A localized but incredible rainfall event is taking place early this
morning, stretching from Jackson county northward to Henry county.
Private weather stations in the Headland area in Henry county have
picked up over 9 inches of rain so far, a large portion of which has
fallen in just 5 hours. Meanwhile, farther south in Jackson county,
the Marianna airport (KMAI) picked up a whopping 3.76 inches of rain
in just one hour. Needless to say, life threatening flash flooding
exists out there early this morning in this corridor. Please be
careful!

As we head through the day, the boundary responsible for this
activity is expected to shift slowly westward. Storms this morning
will eventually weaken, and additional scattered showers and
thunderstorms are expected to develop this afternoon. The flood
watch has been extended through the day.

&&

.SHORT TERM...
(Monday through Tuesday night)
Issued at 308 AM EDT Sun Sep 15 2024

The stationary front may sag a bit farther south on Monday,
perhaps over our western offshore waters. However, there are
differences within the model guidance with some of the global
models showing perhaps a farther north solution and hi-res
guidance a bit further south. Either way, it appears the best
chances for rain on Monday will be across the Panhandle and into
southeast Alabama. Given the close proximity of the front and
ample moisture (PWATs 1.8 to 2.1 inches), still can`t rule out a
heavy rain threat along the coastal Panhandle. Highs Monday will
be in the lower half of the 80s with lows in the upper 60s to
lower 70s.

On Tuesday, the front tries to lift north a bit Tuesday, closer to
or over the Panhandle coast. Again, moisture is still abundant
with PWATs around 1.7 to 1.9 inches, which could lead to a
localized flash flood threat. Best rain chances will be near the
Emerald Coast, though perhaps less coverage overall. Highs will be
in the middle to upper 80s. Lows will be in the upper 60s to lower
70s.

&&

.LONG TERM...
(Wednesday through Saturday)
Issued at 308 AM EDT Sun Sep 15 2024

The stationary front continues to slowly become more diffuse and
move off to the south and east later in the week. The upper-level
pattern will become rather chaotic as the upper-level low
associated with a surface low moving into the Carolinas meanders
southward over the southeast US. However, the stronger northerly
flow will help usher in some drier air to our area, potentially
bringing an end to our very wet pattern. As a result, temperatures
will increase back to the upper 80s to lower 90s with lows
generally in the upper 60s to lower 70s.

&&

.AVIATION...
(12Z TAFS)
Issued at 605 AM EDT Sun Sep 15 2024

In general, ceilings are expected to start out in the MVFR to IFR
range this morning across the area. Scattered showers and possibly a
few thunderstorms are expected to be near DHN this morning
and into the afternoon hours with the best chance of thunderstorms
this afternoon. IFR ceilings this morning are expected to improve to
MVFR later this morning and possibly VFR for a few spots this
afternoon.

&&

.MARINE...
Issued at 308 AM EDT Sun Sep 15 2024

Winds will be generally be light across the waters over the next
several days, but given the presence of a stationary front and
waves of low pressure, wind direction will be variable through the
next 5 days. This front will also keep the weather rather
unsettled with daily chances for showers and storms.

&&

.FIRE WEATHER...
Issued at 308 AM EDT Sun Sep 15 2024

Fire weather concerns are expected to remain minimal with recent
wetting rains, a moist airmass in place, and a chance of showers and
thunderstorms continuing.

&&

.HYDROLOGY...
Issued at 308 AM EDT Sun Sep 15 2024

An extreme event has unfolded late last evening into the overnight
hours. Significant flash flooding was observed over parts of
Henry, Houston, and Jackson Counties with several spots exceeding
an estimated 1-in-200 year annual recurrence interval. Rainfall
totals of 5-10 inches occurred, a good portion of that within a
matter of a couple hours. Given the possibility of additional
bands of heavy rain, have adjusted the Flood Watch to be more over
southeast Alabama, far western Georgia, and the Florida Panhandle
into the western Big Bend. These areas are extremely vulnerable to
any additional rainfall, and it won`t take much to cause issues.
Flash flood guidance is around 1-3 inches in 1 hour or about 2-4
inches in 3 hours. WPC has maintained the Marginal Risk of
excessive rainfall (level 1 of 4) across the Florida Panhandle
Monday and Tuesday as well to account for the potential for
locally heavy rainfall continuing. Can`t rule out isolated areas
of 3-6 inches (or possibly more) through the next couple days.

On the river side, the Kinchafoonee at Preston has crested and is
nearly out of flood stage. The Kinchafoonee and Muckalee basins
should see action stage levels over the next couple days.
Along the ACF, the Chattahoochee at Columbia L&D as well as the
Apalachicola at Blountstown are also forecast to reach action
stage. Depending on where these bands of heavy rain set up, some
of the smaller creeks could see quick rises, and some mainstem
rivers may also see some rises. But currently, no mainstem rivers
are forecast to reach flood stage.

&&

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not requested. However, spotters are always
encouraged to safely report significant weather conditions when they
occur by calling the office or tweeting us @NWSTallahassee.

&&

.PRELIMINARY POINT TEMPS/POPS...
Tallahassee   83  70  82  68 /  60  20  40  20
Panama City   83  72  83  71 /  70  50  70  50
Dothan        80  68  80  67 /  70  50  50  20
Albany        81  69  81  66 /  50  20  30  10
Valdosta      83  69  82  67 /  50  20  30  10
Cross City    87  72  84  70 /  50  20  50  10
Apalachicola  83  73  82  73 /  50  50  70  50

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...Flood Watch until 8 PM EDT /7 PM CDT/ this evening for
     FLZ009>015-026-112-114-115.

GA...Flood Watch until 8 PM EDT this evening for GAZ120>123-142-143-
     155.

AL...Flood Watch until 7 PM CDT this evening for ALZ065>069.

GM...None.
&&

$$

NEAR TERM...DVD
SHORT TERM...Young
LONG TERM....Young
AVIATION...DVD
MARINE...Young
FIRE WEATHER...DVD
HYDROLOGY...Young