809
FXUS62 KMFL 171356
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
956 AM EDT Wed Jul 17 2024

...New UPDATE...

.UPDATE...
Issued at 943 AM EDT Wed Jul 17 2024

The 12Z KMFL sounding shows a good layer of mid level dry air in
place this morning. This is also reflective with PWAT values
coming in at 1.56 this morning. This layer of mid level dry air
will slowly erode as the day progresses from east to west as
moisture advection takes place. While this drier air will help to
reduce overall shower and thunderstorm coverage, there will be
enough lower level moisture to support convection develop as the
sea breezes push inland. The highest chances will remain over the
interior and west coast this afternoon where the sea breeze
boundaries will collide and interact with each other. Due to
reduced coverage of showers and storms this afternoon, high
temperatures will rise into the lower to mid 90s across most
areas. As moisture advection continues today, peak heat indices
will range between 105 and 110 across most areas. With reduced
overall coverage of convection especially across the eastern
areas, the heat indices will remain at their peak values for a
longer period of time. Because of this, a Heat Advisory has been
issued for the eastern half of South Florida through the early
evening hours.

&&

.SHORT TERM...
(Today through Thursday)
Issued at 101 AM EDT Wed Jul 17 2024

Typical mid July pattern will continue across South FL the next
couple days with high pressure over the western Atlantic keeping a
light E/SE flow across the area. Forecast soundings continue to show
mid/upper level dry air, and PWAT values of 1.8-2 inches. Convection
during the afternoon/early evening will favor interior locations and
over towards the Gulf coast, with lower chances across the metro.
Much like the past couple days, a few stronger storms will be
possible especially around the lake and over towards the Naples
area. Slow storm motions will pose a low end flood risk for urban
and poor drainage locations. Overnight scattered showers and
isolated storms will be possible along the Atlantic coast and down
into southern Miami-Dade.

Temperatures today and Thursday will remain toasty, with afternoon
high temps in the low to mid 90s. When combined with dewpoints in
the middle 70s, max heat indices will be 100-105 across much of the
area. While some locations in Collier county may approach Advisory
criteria, expected convection in the afternoon and early evening
should prevent these locations from maintaining Advisory levels for
long. Thus, no heat headlines are expected as of right now.
Overnight lows tonight will be in the middle 70s around the lake, to
lower 80s close to the coast.

&&

.LONG TERM...
(Thursday night through Tuesday)
Issued at 242 AM EDT Wed Jul 17 2024

South Florida will continue to remain positioned along the western
periphery of the broad subtropical ridge for most of the extended
period. Light to moderate east to southeasterly low level flow will
continue to prevail through most of the extended period, with the mean
flow veering more southeasterly at times late this week. With this
ongoing flow pattern, rain chances will continue to be more favored
towards the western half of the CWA as the Atlantic sea breeze will
advance further inland each day and the Gulf breeze will not be
able to penetrate as far. Another factor in precipitation chances
over the weekend and into early next week will be another Saharan
dust plume (SAL) advecting into the region, which is likely to
create drier conditions particularly aloft. This would limit shower
and storm growth potential as well as how widespread
precipitation can become.

Towards the end of the weekend and into early next week, the SAL
will still have an impact on rain chances, but there will also be
the chance for a TUTT to advect through the region and provide
forcing and extra tropical moisture for increased showers and
thunderstorms. The combination of these factors leads to high
uncertainty for the end of the forecast period and thus changes
will be likely for early next week in future forecast updates. For
now, a middle ground approach has been taken with PoPS in the
chance to likely categories (i.e. 50-70%) early next week.

Temperatures are expected to stay in the low to mid 90s range for
highs each day and lows in the upper 70s to lower 80s. Heat
Advisory conditions will continue to be possible each day given
the high moisture leading to high dew points and the daily hot
temperatures in the 90s.

&&

.AVIATION...
(12Z TAFS)
Issued at 728 AM EDT Wed Jul 17 2024

VFR conditions will prevail across the east coast terminals
through the forecast period. Winds will increase out of the ESE
later this morning and will range between 10 and 15 kts this
afternoon. At KAPF, winds will shift to the west as a Gulf breeze
develops this afternoon. Scattered showers and storms will
develop over the interior and west coast as the afternoon
progresses. Periods of sub-VFR conditions will be possible at KAPF
later this afternoon.

&&

.MARINE...
Issued at 101 AM EDT Wed Jul 17 2024

High pressure centered over the western Atlantic will continue to
bring gentle to moderate east to southeasterly wind flow to most of
the local waters through the rest of the week. Seas will generally
remain at 2 feet or less during this time frame across the Atlantic
and Gulf waters. Scattered showers and thunderstorms will be
possible over the local waters each day. This could result in
locally higher winds and seas in and around storms.

&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            93  81  93  81 /  30  20  50  20
West Kendall     92  79  93  78 /  30  20  50  20
Opa-Locka        93  81  93  81 /  30  20  50  20
Homestead        91  81  91  80 /  20  30  50  20
Fort Lauderdale  90  81  91  81 /  30  20  50  20
N Ft Lauderdale  91  81  91  81 /  30  20  50  20
Pembroke Pines   92  81  92  81 /  30  20  50  20
West Palm Beach  91  79  91  80 /  20  10  50  10
Boca Raton       91  80  92  80 /  20  20  50  20
Naples           93  78  92  78 /  30  20  70  30

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 6 PM EDT this evening for FLZ067-068-071>074-
     168-172>174.

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

$$

SHORT TERM...CMF
LONG TERM....Redman
AVIATION/UPDATE...CWC