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Area Forecast Discussion (AFD)

Issued by Key West, FL (KEY)

                            
000
FXUS62 KKEY 200237
AFDKEY

Area Forecast Discussion
National Weather Service Key West FL
1037 PM EDT Sat May 19 2018

.DISCUSSION...
Currently - An Atlantic ridge extends across the southeastern
United States while a small scale trough is embedded in it's 
southwestern flank, near the Florida Keys. Winds have been running
east southeast near 15 knots at most of our marine sites this
evening. Meanwhile, a stubborn upper level trough remains aligned
in the eastern Gulf of Mexico. The combination of these features
continue to stream a moisture plume northwards across the Florida
Keys. The large rain shield that had affected the Middle and Upper
Keys this evening has finally dissipated and shifted northward.
However, another large cluster showers with embedded thunderstorms
are moving north northwestward through the outer Florida Straits. 

Short Term Update - The weak surface trough will slowly shift 
westward through the overnight period allowing a tighter pressure
gradient to fill in across the Keys. Troughing will remain in 
place aloft. The wetter than normal pattern will continue. 
Activity across the Florida Straits will gradually impinge on the 
Florida Keys overnight and many island locations can expect a 
period of light rain interspersed with rounds of showers and 
possibly a few thunderstorms. Expect overnight temperatures in the
mid to upper 70s with much of the range due to rain cooling. Dew 
point temps will hover in the lower 70s. 

&&

.MARINE...
An Atlantic stretching into the southeastern United States and a
weak surface trough moving westwards through the Keys area will
result in a gradually strengthening flow across our waters.
Cautions remain in effect for increasing winds on all waters and
an advisory may be required for the Florida Straits tomorrow.
Mariners can expect higher winds and seas near the stronger
showers and thunderstorms.

&&

.AVIATION...
A wet weather pattern remains in place across the Florida Keys. As
a result, bouts of sub VFR conditions will affect the island
terminals through the overnight period. Surface winds will be out
of the east to southeast at 10 to 15 knots with gusts of 15 to 20
knots. 

&&

.KEY WATCHES/WARNINGS/ADVISORIES...
FL...None.
GM...None.

&&

$$

Public/Marine/Fire...11
Aviation/Nowcasts....11
Data Collection......DR

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