972
FXUS62 KTAE 151531
AFDTAE

Area Forecast Discussion
National Weather Service Tallahassee FL
1131 AM EDT Sat Jun 15 2024

...HOT WEATHER EXPECTED TODAY WITH TRIPLE DIGIT HEAT INDICES...

...New UPDATE, MARINE...

.UPDATE...
Issued at 1120 AM EDT Sat Jun 15 2024

No major changes to today`s forecast were required. Rain chances
were tweaked at the hourly level to account for the latest trends.
The best convective potential remains over the SE FL Big Bend
where a pool of moisture sits on the northern fringe of an
inverted trough near Dry Tortugas.

The 12Z KTAE sounding depicts an unseasonably dry airmass with
Precipitable Water of 1.23". However, 850-mb temperatures are 18.4
C, which is about the 90th percentile, per SPC sounding
climatology. The combination of those factors amidst developing
surface high pressure + 500-mb ridge heights at 587 dm (daily
mean) supports a hot afternoon characterized by triple-digit heat.
Please use caution if outdoors.

&&

.NEAR TERM...
(Today and tonight)
Issued at 427 AM EDT Sat Jun 15 2024

The main story today will be hot and dry weather. At 500 mb, a
lobe of high pressure will move across the Southeast States and
strengthen through tonight. 500 mb heights will be near 5900
meters by this afternoon over the forecast area, with positive 500
mb height anomalies strengthening from the Tennessee Valley
northward. The warm and dry mid-level air will keep cloud coverage
low and shut down prospects for PM convection north of the FL
state line. So peak June solar insolation will have no trouble
boosting inland high temperatures into the 95-100 degree range.
From a heat index standpoint, inland dewpoints in the 60s will
only add a couple degrees to the feels-like temperature. For a few
spots closer to the coast, where the seabreeze will come with
muggy dewpoints into the mid 70s, a few localized spots could eek
out heat index values in the 105-109 range. Coverage of such heat
index values will be too isolated to justify issuance of a Heat
Advisory.

While most of the forecast area will remain rain-free this PM, the
SE Big Bend could be the main exception. Satellite-derived
Precipitable Water (PW) imagery shows the northern edge of deeper
moisture extending up into Dixie, Taylor and Lafayette Counties.
PW values there are in the 1.5-1.7 inch range, with even moister
values just on the other side of the Lower Suwannee River. This
corner of the forecast area will be furthest from the suppressive
effects of the building 500 mb high to the north, and PW values in
excess of 1.5 inches support the notion of afternoon thunderstorm
development along the seabreeze front just inland of the Nature
Coast.

&&

.SHORT TERM...
(Sunday and Sunday night)
Issued at 427 AM EDT Sat Jun 15 2024

A temporary return of deeper and richer moisture is expected on
Sunday. An inverted surface trough is currently located over the
southeast Gulf, not far north of the Yucatan Channel. This feature
will move northwest to the Louisiana coast on Sunday, bringing a
turn of our 1000-700 mb layer flow out of the southeast. In
response, deep and rich tropical moisture characterized by PW
values in excess of 2 inches over the far southeast Gulf will
spread northward and northwestward. This will encompass most of
the forecast area on Sunday, most notably areas along and south
of a Dothan-Valdosta line. Therefore, scattered to numerous
showers and thunderstorms will bubble up in daytime heating for
all but areas north of U.S. Hwy 82, where convection will be more
isolated.

The increase in clouds and convection during the afternoon will
bring a downward trend in high temperatures, though most places
will still be a couple degrees above normal.

&&

.LONG TERM...
(Monday through Friday)
Issued at 427 AM EDT Sat Jun 15 2024

Strong low-mid level high pressure will become anchored along and
just off the U.S. Mid-Atlantic coast on Monday, persisting for
most of next week. Meanwhile, a tropical low pressure system is
likely to be deepening over the Bay of Campeche in the early-mid
week time frame, as reflected in the NHC Tropical Weather Outlook.
The service area will find itself in a pretty tight pressure
gradient between these two features, with unseasonably strong
easterly breezes developing on Monday and then continuing until
about Friday.

Dry air emanating from the strong U.S. Mid-Atlantic high will
spread across the forecast area on Monday in the anti-cyclonic
easterly flow. The dry air should fully encompass the area on
Tuesday and Wednesday. Though the official forecast still includes
isolated PM convection on Tuesday and Wednesday over our FL
counties, ensemble mean PW values well below 1.5 inches suggest
the potential for convective shutdown on those days.

Rain chances start to slowly creep up on Thursday and Friday, as
an easterly wave is likely to track from the Bahamas across the FL
Peninsula and start increasing moisture from the southeast. Timing
of the easterly wave is still all over the place in various pieces
of guidance, so the forecast just reflects a modest broad-brush
day-to-day increase in convective coverage on Thursday and Friday,
with the greatest increase over our Florida and south-central
Georgia counties.

&&

.AVIATION...
(12Z TAFS)
Issued at 630 AM EDT Sat Jun 15 2024

VFR conditions through the period. Easterly winds will clock
around to southerly late today into early tonight at all TAF
sites, remaining below 10 knots.

&&

.MARINE...
Issued at 1120 AM EDT Sat Jun 15 2024

Offshore buoys were reporting easterly winds at 10 kts with 1-2-ft
seas and a dominant period of 6-7 seconds late this morning.

From CWF Synopsis...Gentle to moderate southeast breezes will
develop later today and continue on Sunday, in response to a low
pressure trough moving from the southeast Gulf to the north-
central Gulf Coast. An unseasonable round of fresh to strong
easterly breezes will get underway on Monday and continue through
Wednesday, as pressure gradients tighten between strong high
pressure off the U.S. Mid- Atlantic coast and a deepening area of
tropical low pressure over the Bay of Campeche.

&&

.FIRE WEATHER...
Issued at 427 AM EDT Sat Jun 15 2024

Above normal temperatures will prevail through at least the
middle of next week, along with inland areas of high dispersion
each afternoon. Meanwhile, a dry air mass will hang on over inland
areas today, bringing another round of Min RH values in the 30-35
percent range. Some moistening of the air mass will occur on
Sunday, coming with an increase in coverage of afternoon
thunderstorms. But then a drying northeast to east wind will begin
on Monday. In fact by tame summertime standards, some uncommonly
gusty winds will begin on Monday and persist for much of next
week.

&&

.HYDROLOGY...
Issued at 427 AM EDT Sat Jun 15 2024

Significant or widespread flooding is not expected for the next 7
days. As is common in the summer, the only minor concern is for
intense rainfall rates beneath the core of scattered thunderstorms
which could bring short-lived and very localized runoff issues.

&&

.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   98  75  94  74 /  10  20  50  20
Panama City   94  77  89  76 /  20  20  50  20
Dothan        97  74  94  74 /  10  10  50  20
Albany        97  74  96  74 /   0  10  30  20
Valdosta      98  73  97  73 /  10  10  40  20
Cross City    95  72  94  71 /  60  20  60  20
Apalachicola  89  79  87  78 /  20  30  50  30

&&

.TAE WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk from Sunday morning through late Monday
     night for FLZ108-112-114-115.

GA...None.
AL...None.
GM...None.
&&

$$

UPDATE...IG3
NEAR TERM...Haner
SHORT TERM...Haner
LONG TERM....Haner
AVIATION...LF
MARINE...Haner/IG3
FIRE WEATHER...Haner
HYDROLOGY...Haner