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FXUS62 KMLB 181941

Area Forecast Discussion
National Weather Service Melbourne FL
341 PM EDT Fri Aug 18 2017

Current-tonight...Pending boundary collisions to occur over the
next 2H will dictate PoP coverage for the rest of the afternoon 
as upr drying has limited convective development over much of the
area so far this aftn. The evening forecast features a chc of
storms inland with isolated coverage at the coastal counties
through around 10 PM. The potential remains for some gusty winds 
and locally heavy rain through dusk should some stronger storms 
develop with collisions. 

Sat-Sun...Upper low downstream of the FL peninsula over Yucatan 
channel wl continue slowly west. Overall moisture values remain 
temporarily on the low side area wide and PoP guidance/forecast 
is reduced below climo Sat. Temps will run a few degrees above 
climo with afternoon heat indices approaching 105 to 107. 

From Prev disc...

Slug of deep, tropical moisture advects from SE to NW across CWA 
to east of trough axis late Sat night and into Sun. With deep SE 
flow of moist conditions (PW 2.00-2.25 inches), coverage of 
showers with embedded storms will increase over the Atlantic late 
Sat with scattered activity working onshore, especially SE coast, 
with some isolated nocturnal showers possible even far inland. 
High coverage of showers/storms expected Sun areawide, with best 
chance over central/south CWA (50-60 POP).

Mon-Thu...Ridge axis re-establishes north of CWA next week,
resulting in long fetch of onshore flow across central FL.
Moisture levels lessen early in the week as inverted trough exits
west, causing diurnal storm coverage to return to climo values
(generally 30-40 POPs, possibly a little higher near Lake
Okeechobee and southern Treasure Coast). Global models continue
to display run-to-run inconsistency with handling of next 
tropical disturbance. With unfavorable conditions for significant 
development, best course of action at this point is to show
increase of shower/storm coverage Wed/Thu as swath of higher PW
reaches area in association with inverted trough. Max temps near
to slightly above normal, with mins at least several degrees above
climo, with some coastal locations remaining near 80 for mins
given onshore flow across warm waters. 


VFR outside of showers/thunderstorms. Another afternoon and 
evening of scattered to numerous showers and thunderstorms with 
the highest chances over the far interior, and TEMPO groups have 
been added for LEE, ISM, MCO, and SFB. For the coastal sites, most
showers/storms that form along the east coast sea breeze should 
be to the west, but some storms could make it back to the coast 
late this afternoon and evening from DAB to VRB. Not confident 
enough for TEMPO groups as of right now. The majority of the 
activity should end over the interior around sunset and a few 
hours later for the coastal sites.


Tonight...Fairly quiet over the waters with wind wave of 1-2 ft
near the coast and around 2-3 ft over the outer waters. Storm
coverage will be very sparse at best.  

Sat-Sun...light SE winds increasing to 10-15 kt, especially across
southern waters late Sat/early Sun as axis of inverted trough
reaches south FL. Seas 2-3 ft, up to 4 ft in Gulf Stream.
Scattered to locally numerous showers and storms moving onshore,
especially southernmost waters.  

Mon-Tue...Long SE fetch near 15 kt with seas building to 4-5 ft,
except 3 ft over northern near-shore waters. Onshore flow becomes
more easterly Tue and perhaps lessing a bit as ridge axis builds
far to the north. Long fetch should allow seas to remain elevated
at 4-6 feet across offshore waters and 3-4 ft closer to shore.
Scattered onshore moving showers/storms. 


DAB  76  92  75  89 /  20  20  30  40 
MCO  75  97  77  93 /  30  20  20  50 
MLB  77  93  77  88 /  20  20  30  60 
VRB  74  92  76  89 /  20  20  40  60 
LEE  77  96  77  95 /  30  30  20  50 
SFB  76  96  77  93 /  30  20  20  50 
ORL  77  97  78  93 /  30  20  20  50 
FPR  74  93  76  89 /  20  20  40  60 



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