066
FXUS62 KMFL 270509
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
109 AM EDT Fri Sep 27 2024

...New AVIATION...

.UPDATE...
Issued at 703 PM EDT Thu Sep 26 2024

Tropical Storm warnings remain in effect for all of South Florida,
with a few sustained tropical storm observations reported on both
the east and west coasts this afternoon, and numerous gusts in the
45-65 mph range. We will likely see another couple of hours of
these gusty conditions, but would expect a gradual decrease in
winds into the evening as Helene pulls northward and mixing
decreases. If the decrease in winds materializes, will consult
with NHC on the expiration of Tropical Storm headlines for our
area at the 11PM advisory.

We remain in a zone of relative subsidence on the fringes of
Helene`s circulation which has resulted in a generally dry late
afternoon across SFL. As Helene lifts north-northeast overnight we
will begin to have some tropical moisture associated with the
"tail" of the cyclone lift into portions of SW Florida, so will
focus the highest overnight PoPs in that region... with the east
coast remaining mostly dry.

The greatest remaining concern associated with Helene (for our
area) will be the potential for major tidal flooding over
portions of the coastal SW Florida this evening, refer to the
latest Hurricane Local Statement and Storm Surge warnings for more
information.

&&

.SHORT TERM...
(Rest of today through Friday)
Issued at 128 PM EDT Thu Sep 26 2024

Tropical storm concerns continue across South FL this afternoon as
additional outer bands associated with Hurricane Helene continue
to push across the area. Tropical storm force winds have been
measured across the region throughout the day, with sustained
winds in the 20-30 kt range and gusts in the 40-50+ kt range.
These conditions will persist through the afternoon as the
expansive wind field overspreads the peninsula. While these rain
bands will be moving swiftly across the region, they could still
produce quantifiable rainfall accumulations, leading to possible
flooding concerns through this afternoon. A very limited
possibility of tornadic activity remains for the afternoon as
these bands push through; however, the best dynamics look to have
moved northward along the peninsula, so any rotations that do
develop will most likely be weak in nature.

Helene is expected to make landfall somewhere in the vicinity of the
big bend area of FL this evening, however even as the system moves
inland, trailing moisture will remain across South FL overnight and
through the day on Friday, resulting in additional periods of
showers and thunderstorms. Depending on how much rainfall occurs
today and tonight, the Flood Watch may need to be extended beyond
Friday morning, but that decision will be made later today.

Daytime high temps today and Friday will be in the upper 80s to
around 90. Overnight lows will be very mild, only dropping down to
the upper 70s and lower 80s.

&&

.LONG TERM...
(Friday night through Wednesday)
Issued at 340 AM EDT Thu Sep 26 2024

To start of the weekend, a stream of elevated moisture,
characterized by PWAT values of 2.2-2.4 inches will remain draped
over the region in the presence of persistent southwesterly flow.
This southwest flow, associated with Helene`s extratropical
transition, could enhance low-level convergence, further elevating
hydrologic concerns, especially in areas prone to poor drainage for
the end of the week. The moisture fetch will gradually drift
northward with time, eventually clearing out of the area by Sunday.
For the latter half of the weekend, expect much drier conditions as
a plume of drier air filters in over the region in concordance with
an expanding surface ridge of high pressure.

Through the early/mid-week period, H500 ridging remains dominant,
generally suppressing development of showers and thunderstorms. With
that being said, some remnant moisture may drift southward and allow
for a few showers and isolated thunderstorms to spawn at times.
Overall, expect mostly benign weather and a generally drier pattern
to prevail, with PoPs remaining below climatological ranges through
much of next week.

Strong upper ridging, weak surface winds, and the lack of abundant
rainfall/cloud cover will generally allow for warm temperatures
through the weekend and next week. Maximum temperatures will reach
the low to mid 90s while dewpoints remain in the mid 70s. This may
prompt the issuance of heat advisories and even excessive heat
warnings through the weekend and possibly into portions of next week
as well.

&&

.AVIATION...
(06Z TAFS)
Issued at 106 AM EDT Fri Sep 27 2024

SCT to BKN MVFR ceilings expected through the 06Z TAF period.
Breezy S/SW winds 15-20 kts with gusts to around 30 kts this
morning decreasing slightly to 10-15 kts and gusts around 20 kts
late in the day. SCT thunderstorms today may result in brief
flight restrictions along with erratic winds.

&&

.MARINE...
Issued at 128 PM EDT Thu Sep 26 2024

Tropical storm force winds will prevail across the local waters
through the evening as the region remains under the influence of
Helene`s expansive wind field. Conditions may begin to improve
late tonight, however elevated winds and seas will linger through
at least the end of the day on Friday.

&&

.BEACHES...
Issued at 128 PM EDT Thu Sep 26 2024

Moderate to major coastal flooding/storm surge flooding is
expected along the Gulf Coast tonight as Hurricane Helene
progresses northward towards the Florida panhandle.

Dangerous rip and high surf conditions are expected for all South FL
beaches through at least tonight. Elevated rips should be expected
through at least Friday.

&&

.PRELIMINARY POINT TEMPS/POPS...
Miami            91  79  93  79 /  80  40  30  10
West Kendall     92  78  93  77 /  70  40  30  10
Opa-Locka        92  79  93  79 /  80  50  40  10
Homestead        90  79  92  78 /  70  50  30  10
Fort Lauderdale  91  79  92  79 /  80  50  40  10
N Ft Lauderdale  92  79  93  79 /  80  50  40  10
Pembroke Pines   93  80  95  80 /  80  50  40  10
West Palm Beach  93  79  93  78 /  70  50  50  20
Boca Raton       93  79  94  78 /  70  50  40  10
Naples           89  80  90  80 /  50  70  60  20

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...Tropical Storm Warning for FLZ063-066>075-168-172>174.

     Flood Watch until 8 AM EDT this morning for FLZ063-066-069-070.

     Storm Surge Warning for FLZ069-075.

     High Rip Current Risk through this evening for FLZ168-172-173.

AM...Tropical Storm Warning for AMZ610-630-650-651-670-671.

GM...Tropical Storm Warning for GMZ656-657-676.

&&

$$

SHORT TERM...Carr
LONG TERM....SRB
AVIATION...Carr