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FXUS62 KMFL 212005

Area Forecast Discussion
National Weather Service Miami FL
405 PM EDT Mon May 21 2018

The region remains in a plume of tropical moisture embedded in 
the southeasterly flow between a low pressure over the 
northeastern Gulf and high pressure over the Atlantic. The focus 
for convection today has been over the FL Keys and lifting 
northward into the southwest coast, as well as over northern Palm 
Beach and the Lake Okeechobee region. Further southeast over the 
urban corridor, only passing showers as a ridge of high pressure 
has nosed a little closer to the region and the moist plume has 
shifted just a bit west.

Tuesday, expecting the same general pattern. Slightly higher rain
chances focused interior, west, and north, but still scattered 
showers and maybe isolated thunderstorms over SE FL. 

Wednesday, models indicate potentially the lowest rain chances of
the week, as low pressure reorganizes over the central
Gulf/western Caribbean and the pressure gradient slackens a bit 
over the peninsula. Still, scattered showers and isolated 
thunderstorms and mostly cloudy skies will be the rule.

Later in the week into the weekend, models still differ regarding
the handling of a disturbance expected to lift out of the western
Caribbean into the central or eastern Gulf. That region will be 
in an area of upper diffluence associated with the left exit 
region of an upper jet over the western Gulf, and potentially the 
right entrance region of an upper jet over the southeast states,
encouraging surface pressures to fall.

It's too early to say whether any low development will move more
north toward the northern Gulf coast or more toward the western FL
coast/Panhandle. Either way, it appears south FL will be on the 
east side of this system bringing another surge of moisture 
northward over the state. Given the saturated conditions, we will 
need to watch for the potential for heavy rain again this weekend.


Gradient between the low in the gulf and the high in the Atlantic
is promoting sustained east-southeast winds right near 20 knots
over the open Gulf and Atlantic waters this afternoon, and this 
is expected to continue through Tuesday morning. These winds can 
be hazardous to small craft and operators are urged to exercise 
caution. Winds only slowly diminish Tuesday evening into the
latter half of the week as low pressure retrogrades a bit in the
Gulf and the ridge noses in a little closer to South Florida.
Through the week, scattered to numerous showers and a few
thunderstorms over the waters may lead to locally erratic winds
and briefly higher waves. 


Latest radar imagery shows most of the shra activity concentrated
over the interior moving nw. A few shra will be possible near the 
east coast terminals before they gradually progress west away from
most of the terminals after 15Z. The only exception will be PBI, 
where more shra will be expected near the area a little longer. 
For the west coast, the chances of rain increase into the afternoon.
VFR prevail through much of the period with the exception of a few
MVFR cigs due to any thunderstorm near the area with gusty winds.


High risk of rip currents continues at the Atlantic Beaches
through Tuesday evening due to moderately strong onshore winds. An
elevated risk may continue at least into Wednesday.


West Palm Beach  72  82  72  83 /  40  40  40  40 
Fort Lauderdale  75  82  75  83 /  30  40  40  40 
Miami            74  82  74  84 /  30  40  40  50 
Naples           71  85  72  86 /  50  60  40  50 


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


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