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FXUS62 KMFL 171128

Area Forecast Discussion
National Weather Service Miami FL
628 AM EST Fri Nov 17 2017

VFR conditions will prevail into Saturday.  Light offshore flow (NW 
for eastern terminals) will transition from 14-16z to NE at 10-14 
KT.  This evening, wind will again less to speeds around 5 KT. 
Direction overnight is reflected as NE, but there is reasonable risk 
of NW flow again setting up over the east coast.


.PREV DISCUSSION... /issued 357 AM EST Fri Nov 17 2017/ 

Today through the weekend: lingering low level moisture and a few
showers will affect mainly east coast areas this morning, but 
drier air over Central Florida will make steady southward progress
today and overspread all of South Florida by afternoon. This sets
the stage for a mainly dry and sunny weekend as the surface high 
pressure area over the eastern United States shifts east into the 
Atlantic. A cold front will move down the peninsula on Sunday and
reach the Lake Okeechobee area late in the afternoon, then through
the rest of South Florida Sunday evening. Air ahead of the front 
during the day on Sunday will be too dry to support any
precipitation, with isolated to scattered showers accompanying and
following the frontal passage mainly Sunday evening and night. 

Breezy NE wind today will decrease in time for the weekend. Along
with the drier air, overnight and early AM low temperatures will 
be a touch cooler this weekend, ranging from the upper 50s 
interior SW Florida to the 60s elsewhere. High temperatures will
range within a few degrees either side of 80 degrees. In essence,
temperatures continuing to run very close to average for mid- 

Monday through Thanksgiving Day: weather becomes unsettled for 
Thanksgiving week as the front is expected to stall over the 
Straits of Florida on Monday. As surface/low level winds turn NE 
and E on Monday, clouds and scattered showers will affect east 
coast areas while the interior and Gulf coast squeeze out one more
dry day. A longwave trough looks to set up over the central and
eastern United States as the week progresses, with a strong
shortwave trough coming out of the Rockies and sweeping into the
Gulf of Mexico on Wednesday. The front should respond to the
deepening trough by backing up over South Florida and spreading
increasing clouds and precipitation over the area. Included a
slight chance of thunderstorms on Tuesday as enough instability
should be in place. Consensus of model guidance has the shortwave
trough deepening into a closed low pressure system on Wednesday
slowly progressing eastward, with the ECMWF continuing its trend
of a stronger surface and mid-level low than the GFS. A composite
of the global model guidance points the front becoming nearly
stationary over Central Florida as the closed low in the Gulf 
moves slowly east through Thanksgiving Day. This scenario should 
keep rain chances fairly high Wednesday through Thanksgiving Day, 
but with low confidence in the details of the evolving pattern 
next week, wouldn't be surprised to see changes in timing and 
coverage of any precipitation over the next few days. Temperatures
start off on the cool side Monday morning in the 50s over the 
interior, otherwise lows in the 60s to around 70 and highs around 
80 to the lower 80s will be the rule for much of Thanksgiving 

Small craft caution today Atlantic waters for NE wind 15-20 knots
and seas to 6 feet. Wind and seas subside late tonight, with
decent boating conditions this weekend. A NE swell of 2 feet will
linger over the Atlantic waters through Sunday. Wind and seas
increase late Sunday night with the passage of the cold front,
with caution or perhaps even advisory level conditions possible
early next week over all local waters, along with increasing

A high risk of rip currents will continue today at the Atlantic
beaches with NE wind of 15-20 mph. The rip current risk will
slowly diminish on Saturday but likely remain elevated, before
lowering further on Sunday.

West Palm Beach  79  64  81  63 /  10  10  10  10 
Fort Lauderdale  80  69  81  67 /  30  10  10  10 
Miami            80  68  82  67 /  30  10  10   0 
Naples           80  61  81  63 /  10  10   0   0 


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


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