Flood in Florida, September 29, 2017

Area Forecast Discussion
National Weather Service Miami FL
358 PM EDT Fri Sep 29 2017

.DISCUSSION...
Mid/upper level trough and associated closed low centered over the
northeast Gulf waters combined with the western edge of the Atlantic
high are keeping a prevailing southerly flow aloft across South FL.
Surface low currently over PBI will continue to move north along the
east coast this afternoon. The disturbance is bringing deep tropical
moisture advection from the northern Caribbean and southeast Gulf of
Mexico waters into South FL during the short term period. This will
support periods of light to moderate rainfall over S FL through the
end of the weekend.

At this time, the area of disturbed weather lingering near Cuba is
expected to be near southeast FL tonight into Saturday. NHC in the
latest update has a 40 percent chance of developing into a tropical
cyclone for the next few days. It is expected to move near the South
Florida coast and gradually move north as a surface low pressure and
increase showers and thunderstorms across the area this weekend. Any
tropical development is more likely to be north of S FL. Regardless
of development, the main concern continues to be the potential for
locally heavy rainfall. Rainfall accumulations will range around 1
to 2 inches with locally higher amounts possible. At this time,
Flood Watch has not been issued.

The models show the low migrating north through Saturday with deep
tropical moisture remaining across the area. A surface frontal
boundary will move into the panhandle of FL keeping the plume of
moisture over the region a bit longer. Thus, cloudy and wet weekend
is in store for all S Florida. Due to the expected widespread cloud
cover, temperatures will remain in the mid to upper 80s through the
weekend and warm up to near 90s by mid of next week.

Long term (Sunday night-Thursday)...the forecast for early next week
will depend on the evolution of the sfc low, so a lot of uncertainty
remains. This frontal boundary will play a role in how quickly
conditions will clear improving across the region. Periods of
showers with localized heavy rainfall will remain possible, even
after deeper easterly flow returns across the area by midweek as
high pressure gradually builds over the western Atlantic. The
overall pattern of strong ridge NE and general low pressure SW will
create a tight pressure gradient, bringing periods of breezy
conditons during the first half of next week.

&&

.MARINE...The southerly winds will drop below advisory over the
Atlantic waters early this evening allowing the cancellation of
the SCA at 8PM. The passage of this low pressure will enhance
showers and thunderstorms tonight through the early next week.
Widespread showers and thunderstorms, with locally stronger and
erratic winds, are expected through the weekend.

&&

.BEACH FORECAST...The moderate risk for rip currents on Palm
Beach County beaches continues today and will be lowered to low
Saturday. The rest of the beaches will be kept at low level of
risk for rip currents through the weekend.

&&

.FIRE WEATHER...Light winds and poor mixing will result in prolonged
periods of poor dispersion across South Florida through Saturday.
Numerous to widespread showers and thunderstorms are expected
into the weekend.

&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  74  88  77  90 /  60  50  40  50
Fort Lauderdale  77  89  79  90 /  50  40  30  40
Miami            77  89  78  90 /  50  50  30  40
Naples           75  90  76  92 /  70  50  30  50

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory until 8 PM EDT this evening for AMZ670-671.

GM...None.
&&

DISCUSSION...67/MT
MARINE...67/MT
AVIATION...88/ALM
BEACH FORECAST...67/MT
FIRE WEATHER...67

Hazardous Weather Outlook for South Florida
National Weather Service Miami FL
1143 AM EDT Fri Sep 29 2017

AMZ610-630-650-651-670-671-FLZ063-066>075-168-172>174-GMZ656-657-676-
300345-
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-
1143 AM EDT Fri Sep 29 2017

...MODERATE RISK OF RIP CURRENTS ALONG ALL ATLANTIC BEACHES...
...STORMS MAY PRODUCE HEAVY RAINFALL TODAY...
...CHOPPY CONDITIONS OVER THE OFFSHORE ATLANTIC...

This hazardous weather outlook is for South Florida.

.DAY ONE...THIS AFTERNOON AND TONIGHT

Rip currents: There is a moderate risk of rip currents along all
Atlantic beaches today.

Thunderstorms: Widespread showers with embedded thunderstorms will
move northwest across South Florida through the remainder of the
day. Higher coverage of showers and storms is expected along a
Collier to Lake Okeechobee line later in the day. Frequent lightning
and heavy rain are the main hazards associated with these storms.

Wind: South winds around 20 knots will continue over the offshore
Atlantic waters through this evening.

Flooding: There is a reasonable threat of minor flooding of streets
and poor drainage areas with training or slow moving storms. Ponding
of water may lead to brief lane closures, affecting travel.

Waves: Occasional seas up to 7 feet are possible in the offshore
Atlantic waters, primarily off Palm Beach County, through this
evening.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

A large tropical disturbance stretched out from the northwest
Caribbean Sea into South Florida is expected to lift northwestwards
near the west coast of the Florida peninsula during the weekend.
There is the potential for a weak area of low pressure to develop as
it moves near the Florida peninsula. Regardless of development, a
stormy period is expected to continue across South Florida through
the upcoming weekend with the potential for periods heavy rainfall
leading to localized flooding, along with gusty winds.

.SPOTTER INFORMATION STATEMENT...

Widespread spotter activation is not anticipated, however individual
spotters are encouraged to report flooding and other hazardous
weather 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.