Gale Watch 5, NWS Miami, FL

Area Forecast Discussion
National Weather Service Miami FL
112 AM EST Sun Nov 1 2020

.Aviation...
A meandering boundary continues to act as a focus for SHRA
activity along the east coast. Tomorrow, the boundary should begin
to push south by an approaching cold front. Instability
increases towards the interior and possibly the Gulf coast.
Uncertainty as to timing and location is still high at this time.
The cold front should quickly move through the area Sunday night,
bringing a wind shift and gusty conditions towards daybreak
Monday, near the end or just beyond the KFLL and KMIA TAF periods.

&&

.Prev Discussion... /issued 740 PM EDT Sat Oct 31 2020/

Update...
Scattered showers and isolated thunderstorms will continue across
the region through the evening and into the overnight hours as a
frontal boundary remains in place. Some of the stronger showers
could could contain heavy downpours which could lead to additional
localized flooding across the urban and low lying areas of the
east coast. The shower and thunderstorm threat will continue on
Sunday across the region as this frontal boundary remains stalled
out over the area. There will also remain the potential for
additional localized flooding especially over the east coast
where heavy rain has fallen over the past couple of days. High
temperatures on Sunday will generally range in the upper 80s
across the east coast metro areas to around 90 across the interior
sections.

Prev Discussion... /issued 324 PM EDT Sat Oct 31 2020/

.ROUGH BEACH CONDITIONS FOR MOST OF NEXT WEEK EAST COAST...
.VERY ROUGH MARINE CONDITIONS FOR MOST OF NEXT WEEK...

Discussion...

Short Term (This afternoon into Sunday):

The frontal boundary over South Florida will slowly move
northward to around the Lake Okeechobee region tonight. The
frontal boundary will remain nearly stationary on Sunday around
the Lake Okeechobee region, as high pressure moves east further
into the Atlantic waters. This will keep the steering flow in an
east northeast direction over South Florida during this time.

The showers and thunderstorms that been occurring over the northern
Broward County this morning has shifted into the interior areas
early this afternoon, as the east coast sea breeze has developed
and push inland. As the east coast sea breeze continues to push
inland, the showers and thunderstorms should become more numerous
over the interior and west coast metro areas through rest of the
afternoon hours. The coverage of should then dissipate this
evening, due to the drier air working into the region on the east
northeast wind flow. The drier air will remain in place over South
Florida on Sunday. However, there could still be isolated to
scattered showers and thunderstorms especially over the Lake
Okeechobee region where the frontal boundary remains stationary.
At this time, the primary impacts from the showers and
thunderstorms will be lightning strikes, and locally heavy
rainfall.

Long Term (Sunday night through Friday):

Model guidance depict a semi-stationary frontal boundary
lingering across SoFlo through early next week, keeping enough
low level moisture and marginal instability in place. This will
keep supporting isolated to scattered showers along the southern
and eastern portions of SoFlo through at least Monday when a
secondary front is expected to move across the peninsula. A much
drier air mass descends upon the area in the wake of the later
front and dropping POPs to single digits on Tuesday and Wednesday.

Meanwhile, pressure gradients are expected to increase in the wake
of the FROPA, bringing periods of breezy ENE winds, maybe nearing
or reaching advisory levels at times. By Thursday, the air mass
will gradually modify under veering easterly flow and increasing
moisture advection. Substantial ensemble spreads in the extended
forecast period introduce large uncertainty in the evolution of
the synoptic pattern and associated forecast across South Florida
beyond Thursday. Overall, anticipate an increase in convection
across the region to end the week -- associated with increasing
subtropical or even tropical moisture advection from the
southeast. Deterministic model solutions agree that the pressure
gradient will remain tight through this period, supporting breezy
easterly winds.

Marine...
The winds will remain east northeast at 10 to 15 knots through
tonight before decreasing a little bit on Sunday. The winds will
then become northerly behind the passage of the cold front on
Monday and increase to at least 20 to 25 knots with gusts getting
up to near Gale Force conditions. The winds will remain the 20 to
25 knots with gusts up to near Gale Force conditions for the
middle of next week over South Florida waters, due to the pressure
gradient between the disturbance in the Western Caribbean Sea and
the high pressure to the north.

There is a small northerly swell of 2 to 3 feet that will be
working into the Atlantic waters of Palm Beach County tonight into
Sunday, from the remnants on Zeta that moved off the Mid Atlantic
waters late this week. This will allow for the Atlantic seas in
Palm Beach Waters to increase to 4 to 6 feet on Sunday, while rest
of Atlantic waters of South Florida remain at 3 feet or less. The
Gulf waters will see seas at 2 feet or less on Sunday.

The Atlantic waters will then quickly build to 8 to 10 feet Monday
afternoon behind the passage of the cold front, and remain at
least 7 to 9 feet for the middle of next week. The Gulf waters of
South Florida will quickly build to 4 to 6 feet up to 7 feet well
off-shore on Monday behind the cold front and remain at least 3 to
5 feet up to 6 feet well off-shore for the middle of next week.

Beach Forecast...
The threat of rip currents will remain elevated tonight into
Sunday for the Atlantic waters, and then increase into the
possible High Risk conditions for the early to middle of next
week. The Gulf beaches should also increase for the early to
middle of next week, due to the breezy to windy northerly winds
behind the passage of the cold front late Sunday night into middle
of next week. There could also be rough surf conditions for the
east coast beaches for the early to middle of next week.
&&

.Preliminary Point Temps/PoPs...
West Palm Beach  86  72  79  67 /  30  50  20   0
Fort Lauderdale  88  74  82  70 /  20  40  30  10
Miami            88  74  82  69 /  20  30  30   0
Naples           88  69  80  62 /  40  40   0   0

&&

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

Aviation...13

Hazardous Weather Outlook for South Florida
National Weather Service Miami FL
428 PM EDT Sat Oct 31 2020

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
010830-
Lake Okeechobee-Biscayne Bay-
Coastal waters from Jupiter Inlet to Deerfield Beach FL out 20 NM-
Coastal waters from Deerfield Beach to Ocean Reef FL out 20 NM-
Waters from Jupiter Inlet to Deerfield Beach FL from 20 to 60 NM-
Waters from Deerfield Beach to Ocean Reef FL from 20 to 60 NM
excluding the territorial waters of Bahamas-Glades-Hendry-
Inland Palm Beach-Metro Palm Beach-Coastal Collier-Inland Collier-
Inland Broward-Metro Broward-Inland Miami-Dade-Metro Miami-Dade-
Mainland Monroe-Coastal Palm Beach-Coastal Broward-Coastal Miami-
Dade-Far South Miami-Dade-
Coastal waters from Chokoloskee to Bonita Beach FL out 20 NM-
Coastal waters from East Cape Sable to Chokoloskee FL out 20 NM-
Waters from Chokoloskee to Bonita Beach FL from 20 to 60 NM-
428 PM EDT Sat Oct 31 2020

...MODERATE RISK OF RIP CURRENTS EAST COAST BEACHES...
...LOCALIZED URBAN FLOODING POSSIBLE WITH THUNDERSTORMS...

This hazardous weather outlook is for South Florida.

.DAY ONE...TONIGHT

Rip currents: There is a Moderate Risk of Rip Currents for the
Atlantic beaches.

Thunderstorms: Isolated thunderstorms are possible across South
Florida this evening. The main hazards are lightning and urban
flooding.

Waterspouts: There is a slight chance of a waterspout for the
local waters tonight.

Flooding: Some of the showers and thunderstorms could continue to
contain heavy downpours this evening. This could lead to additional
localized flooding in urban and low lying areas, especially in areas
that have received heavy rainfall earlier today.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

The enhanced risk of rip currents is forecast to continue through at
least the middle of the week.

As a frontal boundary remains in place across the region, urban
flooding will continue to be a risk mainly across the east coast
metro areas for Sunday. A stronger cold front is forecast to move
through for the beginning of the week, which may bring hazardous
marine conditions, especially for the Atlantic waters.

.SPOTTER INFORMATION STATEMENT...

Widespread spotter activation is not anticipated, however individual
spotters are encouraged flooding to the National Weather Service
forecast office in Miami.

For more information...visit the National Weather Service in
Miami website at www.weather.gov/miami.