FXUS62 KMFL 270702
AFDMFL
Area Forecast Discussion
National Weather Service Miami FL
302 AM EDT Sat Jul 27 2024
...New LONG TERM...
.SHORT TERM...
(Today through Sunday)
Issued at 115 AM EDT Sat Jul 27 2024
A seasonably dry airmass (PWATs generally 1.5-1.7 inches) remains
in place over South Florida, with a shortwave ridge axis in place
over the NE GOM and a decaying mid-lvl low progressing westward
into the eastern Bahamas. At the lower-lvls, light SErly flow will
prevail today, with decent inland progression of both sea breezes
expected this afternoon. Tropospheric moisture will increase
marginally (PWATs up to 1.8-1.9 inches) as the decaying mid-lvl
vort approaches with scattered to numerous showers and
thunderstorms expected to develop on both sea breezes this
afternoon. Although convection should have a general tendency to
propagate towards the interior with time, it remains to be seen
if convection initiates over the metros or inland. Regardless, the
only threats would be the usual locally heavy rainfall and gusty
(but sub-severe) wet microbursts.
The weakening of the synoptic flow will allow for slightly warmer
heat indices than the last couple of days, with heat indices
generally peaking in the 103-108 degree range this afternoon.
Consequently decided to issue a heat advisory today for
Broward/Miami-Dade counties, although verification will likely be
dependent upon when and how far inland convection initiates (a
further east initiation may keep things slightly cooler than
forecast).
Sunday will see a slight change from the pattern of the last few
days as a weak frontal system dips into the SE US supporting the
northward transport of more seasonable deep-layer moisture (i.e.
PWATs > 2 inches) into the area. Consequently expect greater
precipitation coverage than we have observed the last several
days, particularly over the Lake region where the low-lvl (sea-
breeze driven) convergence should be maximized. Additionally, we
will likely flirt with heat advisory criteria over portions of the
area again, but this will be dependent upon the timing of
convective initiation and convective coverage.
&&
.LONG TERM...
(Sunday night through Friday)
Issued at 300 AM EDT Sat Jul 27 2024
As we move into the new week, the wave will progress across the US
east coast assisting the frontal boundary further through the
southeastern US. This will keep the deep layer moisture in our
portion of the state, with a considerable increase as we move into
Monday. Precipitable water values will rise to 120% of normal, with
long term ensembles forecasting PWAT values reaching 2.2 - 2.4" on
Monday and Tuesday. With this moisture and veering steering flow,
convective activity will remain widespread, rather than the usual
easterly flow, with an especially high rainfall totals forecast for
Monday and Tuesday. Convective initiation is likely across the
interior of the state, but outflow generated convection will likely
drift towards the coasts. Model guidance continues to forecast
widespread activity, with higher PoPs (60-70%) & QPF values,
present early in the new week. The WPC has a majority of South FL
at a marginal risk for excessive rainfall on Monday and Tuesday.
While a Saharan dust layer continues to remain visible on
satellite imagery across the west-central Atlantic, forecasts keep
the core of this plume passing to our south early next week with
little to no impact likely on the atmospheric moisture and
convective activity.
As we move into mid-week, a stronger easterly flow returns with a
building ridge, thus bringing the region back into the easterly
summer regime for the latter half of the week. Thus, we will return
to early coastal showers along the east coast, followed by
interior/Gulf breeze driven SW FL late afternoon showers.
With plenty of low-level moisture, combined with near normal low to
mid 90 degree temperatures, heat indices and other heat metrics will
remain in an elevated state into next week. This will keep South
Florida flirting with potential for heat advisory conditions. Daily
product issuance will be dependent on the timing of daily convection
and coverage.
&&
.AVIATION...
(06Z TAFS)
Issued at 115 AM EDT Sat Jul 27 2024
Generally VFR conditions will prevail through the morning,
although a brief restriction due to isolated showers will be
possible at the east coast terminals. Scattered thunderstorms will
develop this afternoon, although confidence is not high in whether
they will impact the terminals or remain inland. Light and
variable winds overnight will trend E-SE at the east coast
terminals, and W-SW at KAPF by this afternoon.
&&
.MARINE...
Issued at 115 AM EDT Sat Jul 27 2024
Gentle southeasterly winds will prevail over the Atlantic waters
through the upcoming weekend, while winds over the Gulf waters will
likely shift to the SW during the afternoons in response to the Gulf
breeze circulation. Seas will generally decrease to 2 feet or less
through the weekend, outside of any thunderstorms which could
produce locally higher seas.
&&
.PRELIMINARY POINT TEMPS/POPS...
Miami 93 80 94 79 / 40 20 60 20
West Kendall 93 77 95 77 / 50 20 60 20
Opa-Locka 93 79 95 79 / 50 20 60 20
Homestead 91 79 92 79 / 40 20 50 20
Fort Lauderdale 90 79 92 79 / 40 20 60 20
N Ft Lauderdale 92 79 92 79 / 40 20 60 20
Pembroke Pines 95 78 96 78 / 50 20 60 20
West Palm Beach 93 78 93 78 / 50 20 60 30
Boca Raton 93 78 94 79 / 40 20 60 30
Naples 92 78 92 79 / 50 30 40 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory from 10 AM this morning to 7 PM EDT this evening
for FLZ071>074-172>174.
AM...None.
GM...None.
&&
$$
SHORT TERM...Carr
LONG TERM....JS
AVIATION...Carr