571
FXUS62 KMFL 200716
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
316 AM EDT Fri Sep 20 2024

...New DISCUSSION, SHORT TERM, LONG TERM, MARINE, BEACHES...

.SHORT TERM...
(Today through Saturday)
Issued at 309 AM EDT Fri Sep 20 2024

Models depict a frontal boundary finally pushing across SoFlo today,
with its parent mid level trough lingering across northern FL and
the SE CONUS. Deeper NE flow begins to filter in the wake of the
FROPA, ushering drier air from the north. Model soundings suggest
PWATs decreasing to below 2 inches by this afternoon, and with max
POPs in the 50s. But the influence of the decaying boundary and the
mid level trough to the north will still provide enough support for
scattered showers and thunderstorms this afternoon. And as in
previous days, the weak sfc flow will allow for sea breeze
boundaries to again become focal points for deeper convection. Main
concerns remain with potential for localized flooding, especially
over locations with saturated terrain.

Ensembles and ECMWF insist in pushing the aforementioned mid-lvl
trough further south and through SoFlo on Saturday. In response,
deeper ENE flow establishes, although still remaining weak
(generally 3-8kt). This will be reinforced by broad high pressure
developing over much of the SE CONUS, which will also usher drier
air into the mid levels across the state. Nevertheless, hydro
models keep at least chances for afternoon scattered showers and
isolated thunderstorms, with POPs in the 40-50 percent.

Temperatures and heat indices are expected to remain above seasonal
climo, but stubborn cloudiness and possible rain activity should
help in avoiding advisory criteria through the period.

&&

.LONG TERM...
(Saturday night through Thursday)
Issued at 309 AM EDT Fri Sep 20 2024

As we wrap up the weekend and move into the new week, an expansive
mid-level ridge will stretch across the Gulf of Mexico and into
southeastern CONUS as the lingering trough drifts into the Atlantic.
With this ridging, dry mid-level air will advect into the region
with warm temperatures aloft. Although the mid-level drying is quite
evident, with PWATs dipping down into the 1.4-1.7" range over
portions of the area, there will be enough moisture remaining in the
lower level with the assistance of a stationary surface boundary
just to the south of the Keys keeping a sufficient supply of
moisture in the southern half of the Peninsula. This will support
daily scattered showers and isolated thunderstorms across the
region. With the persistent easterly flow regime, the highest chance
for rain will be over the western portions of South Florida. The
relatively stable airmass will limit the deep convection most likely
to the far southern third of the FL Peninsula.

Looking further into the extended forecast, confidence is still
minimal, as uncertainty increases if a portion of the Central
American Gyre may consolidate into a more defined area of surface
low pressure over the northwestern Caribbean or southern GOMEX (if
forms at all). With the expansive forecast lead times, we will
continue to monitor the tropics as the limited model guidance is
indecisive and jumbled at the time being. In the upcoming days and
as confidence grows, we will be watching the potential for the low`s
development and the Gulf of Mexico`s future closely. The latest
National Hurricane Center 2AM outlook has a 40% chance of tropical
formation in the next 7 days.

Temperatures will be near/just above seasonal normals with high
temperatures in the upper 80s to low 90 and lows in the 70s. While
the heat indices will likely reach the triple digits, the drier air
will likely provide a relief from heat advisories due to dew points
dropping into the low to mid 70s.

&&

.AVIATION...
(06Z TAFS)
Issued at 140 AM EDT Fri Sep 20 2024

Less coverage today in terms of showers and thunderstorms,
but still chances are high enough to carry at least VCTS
for the afternoon hours. Light and variable winds this morning,
then becoming light to moderate from the east to northeast across
the east coast metro areas. Winds become light and variable again
after 00Z.

&&

.MARINE...
Issued at 309 AM EDT Fri Sep 20 2024

Generally light winds continue today with a decaying frontal
boundary moving across the area. Showers and thunderstorms will
begin decreasing today as drier air slowly filters from the north
behind the front. But there will be enough leftover moisture for
isolated to scattered thunderstorms to develop in the afternoon
hours, then the decreasing tend continues into the weekend. Brief
periods of rough seas and gusty winds may accompany any thunderstorm
that forms.

&&

.BEACHES...
Issued at 309 AM EDT Fri Sep 20 2024

Minor to moderate coastal flooding continues during periods of
high tide. These elevated tides will continue to affect all
coastal areas of South Florida through late this morning, for
which a coastal flood advisory remains in effect. For the rest of
the weekend, a decrease in northerly swell should help reduce the
risk for moderate flooding, but some minor flooding could still
be possible through at least late Saturday. Additionally, a
moderate risk of rip currents continues for the Palm Beaches
during the next couple of days.

NAPLES HIGH TIDE TIMES...2:57PM this afternoon

LAKE WORTH HIGH TIDE TIMES...10:24 AM this morning


&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            89  76  90  76 /  50  40  40  30
West Kendall     90  74  91  74 /  60  40  50  30
Opa-Locka        90  75  91  76 /  50  40  40  20
Homestead        89  75  90  76 /  50  40  50  30
Fort Lauderdale  88  76  88  76 /  50  40  40  30
N Ft Lauderdale  89  77  90  76 /  50  40  40  20
Pembroke Pines   91  77  92  77 /  50  30  40  20
West Palm Beach  90  76  90  76 /  60  30  30  20
Boca Raton       90  76  90  76 /  60  30  40  20
Naples           90  75  92  76 /  40  20  30  10

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory until 5 PM EDT this afternoon for FLZ069-
     075-168-172>174.

AM...None.
GM...None.
&&

$$

SHORT TERM/MARINE/BEACHES...17
LONG TERM....JAS
AVIATION...17