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National Weather Service Miami FL
1044 PM EDT SAT JUL 23 2016

.UPDATE...
As of 1045 PM EDT...A relatively late start to the convective
activity has resulted in continued convection across portions of
South Florida this evening. This activity has produced some
localized heavy rainfall, with radar estimates around 3 inches in
portions of Miami-Dade county, along with frequent to excessive
lightning.

Continue to monitor a thunderstorm cluster in Broward/Palm Beach
counties, as well as a secondary cluster in the local Gulf waters
off Mainland Monroe county, as these storms continue to feed off
outflow boundary interactions from earlier evening convection.
These clusters should continue for the next 1-2 hours before
finally dissipating. The primary threats will be frequent
lightning and locally heavy rainfall.

Have adjusted PoPs over the next few hours to account for ongoing
convection, as well as increasing to chance over the Atlantic and
Gulf waters through the remainder of the overnight as near term
guidance suggests additional widely scattered showers/embedded
thunderstorms will be possible. After midnight, land areas are
expected to be dry except for a stray shower along the immediate
coasts. Low temperatures will be in the 70s.

&&

.PREV DISCUSSION... /issued 805 PM EDT SAT JUL 23 2016/ 

AVIATION...
The winds will be light and variable tonight at all of South
Florida taf sites before going easterly 5 to 10 knots on Sunday.
The only exception to this is at KAPF taf site where the winds
will go westerly after 18Z Sunday, due to the develop of the west
coast sea breeze pushing inland. 

The weather should remain dry tonight at all of the taf sites,
before some showers develop in the morning hours on Sunday with
thunderstorms on Sunday afternoon. Therefore, VCSH between 14Z and
17/18Z Sunday then VCTS after 18Z sunday.

The ceiling and vis should remain in the VFR conditions tonight
into Sunday at all of South Florida taf sites. The only exception
is Sunday afternoon where the ceiling and vis could fall down into
MVFR or even IFR conditions with any passage of thunderstorms.

AVIATION...54/BNB

PREV DISCUSSION... /issued 718 PM EDT SAT JUL 23 2016/ 

UPDATE...
At 710 pm edt, large clusters of active thunderstorms were
observed over western Hendry and Collier counties. Meanwhile, a
large single cell was producing frequent lightning over north
central Miami-Dade county and slowly drifting southeast. Flow at
the surface remains light enough to keep most of the remaining
shower/thunderstorm activity nearly stationary, with several
outflow boundaries pushing through the eastern half of South
Florida.

Evening forecast still carries scattered coverage through midnight,
especially along the Gulf coast where the aforementioned convection
may linger during the next couple of hours or so.

The overall synoptic pattern continues to be dominated by strong 
high pressure across most of the south and southeast states, keeping
the Florida peninsula under a generally light easterly and southeasterly
flow through the rest of the weekend. Expect sea breezes to once again
become the focal point for afternoon convection on Sunday.

PREV DISCUSSION... /issued 350 PM EDT SAT JUL 23 2016/ 

DISCUSSION...
Short term (tonight-Mon)...models continue to depict drier air
entrainment aloft as a 500 mb ridge gradually builds across the
region tonight. Meanwhile, low level moisture also continues on a
downward trend with latest MFl sounding data showing PWATS below 2
inches. This has translated into a lesser active afternoon across
South Florida weather-wise. As advertised, most of the afternoon
convection developed along the sea breeze boundaries, and with
the strongest cells lingering along the Atlantic coastline. Synoptic
flow remains very light, which will keep any additional showers or
thunderstorms that form nearly stationary through the evening
hours.

Low level moisture may get a boost on Sun as a tropical wave feature
moves to the south of the state. The best chances of showers and
thunderstorms will reside over interior and Gulf coast areas as
the east coast sea breeze should be a little stronger Sun
afternoon. Wide spread shower coverage is expected during the
afternoon and early evening hours. The west coast sea breeze will
also serve as a focal point for afternoon convection. Despite the
shower activity, high temperatures will remain warm, ranging form
the upper 80s to lower 90s. Sun night will be less active with
mainly scattered showers lingering over the area, mainly during
the evening hours.

A similar weather pattern continues into Mon with afternoon and evening
scattered showers and thunderstorms, along with prevailing southeasterly
flow. This will keep best chances of rain over interior and Gulf Coast
areas.

Long term (Tue-Fri)...overall, the long term will continue to be
dominated by the strong high pressure persisting across the
southeast and southern states with generally weak southeasterly
flow over South Florida. 

Latest satellite and global model analyzes are suggesting a
potential intrusion of Saharan dust into the western Atlantic air
mass, which could limit convective activity across the area if it
materializes. But with the influence of the tropical wave in the
west Caribbean still keeping some low level moisture lingering
over South Florida, and a gradual weakening of the ridge aloft,
will keep carrying at least scattered showers and thunderstorms
each afternoon. The driest day seems to be Thu, but this might be
adjusted depending on the overall timing of all the aforementioned
features. Temperatures should remain around climatic values
through the long term period.

AVIATION...
Showers and thunderstorms are developing along the sea breeze this
afternoon. They will have little movement for the next couple of
hours, then development should trend inland, away from the TAF
sites. Have now added in the mention of TS, through at least 20z
for most sites. After that, they will still be around, but should
be out of the 10sm radius. By this evening, the wind will go
light and variable, and may not increase tomorrow until sometime
in the middle of the day.

MARINE...
Generally light easterly flow will persist over the coastal
waters through the rest of the weekend, 5-10 knots. Only exception
will be with any thunderstorms that form, which will generate
brief periods of locally strong gusty winds, rough seas and
frequent to excessive cloud to water lightning. Seas should remain
around 3 feet or less with little to no swell.

Winds will veer to a more southeasterly flow early next week, and
becoming moderate at times later in the week. 

&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  76  89  76  90 /  30  50  30  60 
Fort Lauderdale  77  88  76  89 /  30  50  40  50 
Miami            76  89  77  90 /  30  50  40  50 
Naples           76  87  74  89 /  20  50  20  50 

&&

.MFL Watches/Warnings/Advisories...
FL...None.
AM...None.
GM...None.
&&

$$

UPDATE...92/IRL
SHORT TERM...17/AR
LONG TERM....17/AR
AVIATION...54/BNB

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