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FXUS62 KMFL 200555

Area Forecast Discussion
National Weather Service Miami FL
155 AM EDT Fri Oct 20 2017

VFR conditions are likely to prevail through the TAF period at 
all terminals. Through the pre-dawn hours, low-level moisture 
will continue to stream WSW-ward from the Atlantic and across the
peninsula. A few short-lived light showers will be possible in 
the vicinity of east coast terminals. The atmosphere will be
slightly drier tomorrow, and isolated shower activity should not 
have any significant impact on airport operations. NE-ENE winds 
will remain around 10 kts through 15Z this morning before 
increasing to 13-16 kts with gusts of 19-22 kts by early afternoon
for east coast terminals. ENE Winds at PBI and FLL will then 
remain strong through Friday evening.


PREV DISCUSSION... /issued 747 PM EDT Thu Oct 19 2017/ 

Radar and satellite data show most of the shower activity
happening south of a line from Naples to Boca Raton, which is
associated with a lingering frontal boundary located near the
Florida Keys. POPS/WX will be adjusted to reflect this trend, but
still keeping low-end chances of rain for Palm Beach county 
through the rest of this evening. 

A drier pattern should establish Friday as the frontal boundary
continues to dissipate, although there will be enough remnant
moisture for another round of afternoon showers. 

rest of the forecast looks good and no further changes are
required for the evening update. 

PREV DISCUSSION... /issued 405 PM EDT Thu Oct 19 2017/ 

Short term (Tonight-Saturday)...satellite and model data depict a
lingering stationary frontal near the Florida Keys, and keeping a
large swath of enhanced moisture across South Florida. Not much 
so far in terms of heavy rain, but there are scattered small cells
moving NE to SW, bringing brief periods of moderate rain at 
times. This shower activity will continue through Friday, although
a decrease in activity is expected later tonight. A few brief 
thunderstorms are also possible. 

Expect scattered showers and isolated thunderstorms each day, 
with best chances during the afternoon hours. Temperatures 
should remain near normal values. Current moderate N/NE winds will
gradually veer to the ENE starting Friday and through Saturday as
high pressure starts building across the region in the wake of the

Long Term (Saturday night-Wednesday)...strong high pressure is 
shown by the models building across the western Atlantic and the 
SE states Sunday and Monday, with tighter pressure gradients 
resulting in periods breezy winds. These winds will become mainly 
easterly early next week. 

Global model solutions show another trough deepening over the
eastern half of the US, sending an associated cold front into 
Florida by Tuesday. Expect an increase in atmospheric moisture 
early next week as winds become SE and then S as the cold front 
approaches. Models agree in pushing the front into the Florida 
Keys by Wednesday. This front may finally bring a significant
change in temperatures, with cooler conditions and lowering dew 
points. In other words, the first days of fall-like weather. 

N/NE winds continue during the next few days, with speeds to 20
kts on Friday. Winds will become more easterly later in the
weekend but will remain breezy through the weekend. Seas in the
Atlantic waters will be up to 5 to 7 feet for the rest of the week
and into the first part of the weekend.

Stronger NE-E winds for the upcoming weekend may combine with high
astronomical tides, bringing water levels along the east coast 
to near coastal flood criteria. A Coastal Flood Advisory remains
in effect for Palm Beach County through Saturday. This may need 
to be extended southward to include Broward and Miami- Dade later 
this week if conditions warrant.

West Palm Beach  81  86  79  88 /  40  50  50  40 
Fort Lauderdale  80  86  79  87 /  50  50  60  40 
Miami            79  87  79  88 /  50  50  60  30 
Naples           75  90  75  91 /  10  50  30  40 


FL...High Rip Current Risk through Saturday evening for FLZ168-172-

     Coastal Flood Advisory until 8 PM EDT Saturday for FLZ168.

AM...Small Craft Advisory for hazardous seas until 8 PM EDT Saturday 
     for AMZ650-670.

GM...Small Craft Advisory until 10 AM EDT this morning for GMZ676.



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