732
FXUS62 KMFL 181709
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
109 PM EDT Mon Aug 18 2025

...New AVIATION...

.UPDATE...
Issued at 1225 PM EDT Mon Aug 18 2025

Forecast remains on track for today as a late start to convection
is expected in the late afternoon and extending into the evening.
With a weak flow pattern, the sea breezes still look to be the
primary initiator with convection today and steering flow looks to
be south/southwest due to conditions mentioned in the previous
discussion. PoPs today peak around 30-40% for the east coast and
70-80% for interior and SW Florida. For tomorrow, rain chances
become more uniform across the region at 60-70%. High temperatures
will continue to reach the mid 90s each day.

&&

.SHORT TERM...
(Today through Tuesday)
Issued at 102 AM EDT Mon Aug 18 2025

Monday begins just like any other typical summertime day in South
Florida. Very weak east-southeast flow prevails early in the day as
mid to upper level ridging retreats and leaves South Florida in the
absence of significant synoptic influence. As the day progresses,
Hurricane Erin slowly enters the picture and surface flow tries to
attain a more northerly direction over local waters, while flow
remains extremely weak over land. Sea breezes are expected to be the
primary driver of convection as Hurricane Erin remains well towards
the southeast, although as sea breezes progress inland, northeast
flow will develop across the eastern half of the area with
northwest flow over the western half of the area. This will create
kind of a unique scenario where convection begins to develop
along the sea breezes and slowly pushes towards the south.
Overall, with such weak background flow the storm movement will
be slow and close to the metro areas. Convection will likely
begin across far western parts of the east coast metro areas and
very slowly progress inland and eventually towards the south as
the afternoon and evening progress. There will likely be a sharp
gradient in cloud cover, with sunshine remaining only over the
immediate coastal areas and barrier islands. Generally quiet
conditions should prevail overnight Monday into Tuesday, although
some high-res guidance is hinting at a slower halt to convection,
with some activity lingering into the first half of the night.

On Tuesday, Erin continues to propagate northward and is forecast to
make its closest pass to the peninsula well off to the east. This
is where we begin to see slightly stronger and more uniform
northerly flow develop across the area. A few coastal showers will
be possible during the morning hours, but shower and thunderstorm
activity will begin to increase across land areas by the early
afternoon hours as daytime heating is maximized. A similar
evolution is expected through the day with a general southerly
motion to the showers and thunderstorms. As the day progresses, we
should see surface flow beginning to veer more northwesterly
which will possibly advect the focus of convection across the far
southern portions of the area, including more of the Miami-Dade
and Broward metro areas than on Monday. All of this is dependent
on the progression of Hurricane Erin, and slight deviations in the
storm speed or motion could change timing for wind shifts across
Florida, which would impact the exact propagation of local
thunderstorms.

&&

.LONG TERM...
(Tuesday night through Sunday)
Issued at 102 AM EDT Mon Aug 18 2025

Hurricane Erin remains the primary synoptic feature
through much of the long term period. As this system continues
northeastward, surface flow across South Florida veers more westerly
by Wednesday afternoon and will remain west-southwest through much
of the period. The only exception is along the immediate east coast
where a sea breeze will attempt to develop each afternoon and we
could see brief periods of southerly or even southeasterly winds in
these regions. A drier airmass moves in on Wednesday facilitated by
Hurricane Erin`s circulation which could act to reduce rain chances
during the mid-week period. PWATs will range from 1.6 to 1.7 inches,
which could support a few isolated showers and storms but mostly
sunny conditions should prevail overall on Wednesday. On Thursday
and Friday a bit more moisture is able work into the area,
especially over the Lake Okeechobee region including Glades, Hendry
and Palm Beach counties, and this is where we should see most
showers and storms on Thursday and Friday afternoon, potentially
progressing eastward towards towards coast by the evening as
westerly flow continues to prevail, albeit very light.

Heading into the weekend, Hurricane Erin`s influence begins to
weaken leaving South Florida without much synoptic influence at
all. Surface flow weakens significantly which should allow for a
more typical sea breeze pattern to dominate for Saturday and
Sunday, with an eastern breeze able to push inland and focus
convection across interior and Southwest portions of the area.

Temperatures should range from the low to mid 90s through the
period, with heat index values ranging in the low 100s to around
105, potentially dancing around Heat Advisory criteria, so this
potential will be monitored each day.

&&

.AVIATION...
(18Z TAFS)
Issued at 108 PM EDT Mon Aug 18 2025

Scattered showers and thunderstorms this afternoon into early
evening may result in brief flight restrictions. Easterly winds
this afternoon around 10 kts for most sites, with a westerly Gulf
breeze this afternoon at APF.

&&

.MARINE...
Issued at 102 AM EDT Mon Aug 18 2025

Pattern change begins Monday as distant Hurricane Erin`s outer
circulation begins veering winds across Atlantic waters to a more
north-northeasterly direction. Light and variable winds across Gulf
waters to begin the day, and will be veering to a more northwesterly
direction by the afternoon. Winds will remain northeasterly for the
first half of Tuesday, but will be veering to a more north-
northwesterly direction through the day on Tuesday. Wave heights
remain at one foot or less for Atlantic waters on Monday and Gulf
waters on Monday and Tuesday. Wave heights increase to 3-4 feet
across northern Atlantic waters on Tuesday. The only exception is
around thunderstorms, which could provide brief periods of rough
seas and gusty winds.

With the passage of Erin to the east of the Florida peninsula mid-
late week, local Atlantic waters could see an increasing north-
northeasterly swell during this time period.

&&

.BEACHES...
Issued at 102 AM EDT Mon Aug 18 2025

Increasing swell from Erin is expected as early as Tuesday, but more
likely mid to late week. This will result in an increasing rip
current threat for the Atlantic beaches and possible high surf
concerns for Palm Beach county.

&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            80  93  78  95 /  20  60  30  40
West Kendall     77  93  76  94 /  30  60  30  40
Opa-Locka        79  95  78  96 /  20  60  30  50
Homestead        78  93  78  93 /  30  60  30  40
Fort Lauderdale  80  92  78  94 /  30  60  30  50
N Ft Lauderdale  80  93  78  95 /  30  50  20  50
Pembroke Pines   80  96  79  97 /  20  60  30  50
West Palm Beach  78  93  77  95 /  30  50  20  60
Boca Raton       78  94  77  97 /  30  50  20  50
Naples           78  93  79  92 /  30  60  30  40

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
&&

$$

SHORT TERM...Rizzuto
LONG TERM....Rizzuto
AVIATION...Redman