347
FXUS62 KMFL 260741
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
341 AM EDT Thu Sep 26 2024

...New LONG TERM...

.SHORT TERM...
(Today through Friday)
Issued at 127 AM EDT Thu Sep 26 2024

*** KEY POINTS FOR HURRICANE HELENE ***

Impacts for South Florida: Hurricane Helene will bring about heavy
rain, gusty winds, storm surge across the Gulf Coast, and increased
flooding potential as its outer bands move across the region. A
Tropical Storm Warning is in effect for all of South Florida,
including the local waters, through at least late Thursday night.

Flood Watch Issued: A Flood Watch is in effect for all of South
Florida, as rainfall amounts of 2-4 inches are possible across
inland and metro areas, with isolated higher amounts possible.

Storm Surge Risk: 2-4 feet of storm surge is expected along the Gulf
Coast from Bonita Beach to Flamingo due to Helene`s size and the
shallow Florida shelf. Values as high as 5 feet may be observed. A
Storm Surge Warning is in effect for these coastal areas.

Tornado Threat: Several tornadoes are possible today, especially
over SW FL and around the Lake Okeechobee region.

***

South FL is experiencing a bit of a lull early this morning, however
additional rain bands associated with Hurricane Helene are expected
to cross the area during the day and into this evening. While storm
motions will be brisk, high rainfall rates along with training
storms will present a urban and poor drainage flood risk today and
tonight across all of South FL. Because of this, a Flood Watch
remains in effect until Friday morning.

Winds will be breezy today and tonight across the area. Most of the
time sustained winds will be below tropical storm strength in the 20-
30 mph range, however gusts of 40-50+ mph will remain possible with
any convection that moves across the area. A Tropical Storm Warning
remains in effect for all of South Florida through at least late
tonight. Due to the large size of Helene, the extent of storm surge
flooding will be present all the way down the Gulf side of the
peninsula. A Storm Surge Warning remains in effect for Collier and
Mainland Monroe, where 2-5 ft of surge is possible along the coast.

There will also be a tornado threat today beginning this morning
and extending through at least the afternoon hours. Most favorable
area will be across SW FL and around the lake region, however
anywhere in South FL should be alert for the possibility of a tornado.

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 127 AM EDT Thu Sep 26 2024

Poor aviation conditions expected today as impacts from Hurricane
Helene are felt across South FL. S/SE winds increase to 20-30 kts
with gusts approaching 40 kts at times, especially during times of
convection. MVFR ceilings will be prevailing however some periods
of IFR/LIFR ceilings and visibilities are possible during periods
of heavy rain.

&&

.MARINE...
Issued at 127 AM EDT Thu Sep 26 2024

Dangerous winds and seas expected for all South FL waters through at
least late tonight. Tropical Storm Warnings remain in effect.
Conditions 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 127 AM EDT Thu Sep 26 2024

Moderate to Major coastal flooding is possible today along the Gulf
coast as Hurricane Helene tracks northward in the eastern Gulf of
Mexico.

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            90  81  91  80 /  70  60  80  30
West Kendall     90  80  91  79 /  70  60  80  30
Opa-Locka        90  81  92  80 /  70  60  80  30
Homestead        89  81  90  79 /  70  60  80  40
Fort Lauderdale  89  80  90  80 /  70  60  80  30
N Ft Lauderdale  90  81  92  80 /  70  60  80  30
Pembroke Pines   92  82  93  81 /  70  60  80  30
West Palm Beach  91  81  92  79 /  70  60  70  30
Boca Raton       92  81  92  79 /  70  60  80  30
Naples           88  82  89  80 /  80  80  70  60

&&

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

     Flood Watch through Friday morning for FLZ063-066>075-168-
     172>174.

     Storm Surge Warning for FLZ069-075.

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

     High Surf Advisory until 8 PM EDT 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...CMF
LONG TERM....SRB
AVIATION...CMF