Area Forecast Discussion
Issued by NWS Melbourne, FL

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FXUS62 KMLB 191940

Area Forecast Discussion
National Weather Service Melbourne FL
340 PM EDT Mon Apr 19 2021


...Heavy Rain Potential Continues through Midweek...

Current-Tonight...Frontal movement southward is evidenced well in
radar trend over the last few hours, as strong thunderstorms have
shifted southward, reaching coastal Brevard County and now
exiting south of Lake Okeechobee and coastal Palm Beach County.
The front is currently analyzed from New Symrna Beach to Tampa
Bay, just a few miles south from the morning analysis placement.
After a brief lull in activity earlier this afternoon, showers and
storms quickly ramped up, but generally remained below strong
thresholds. Convection streaming across the peninsula from the
Gulf has mostly weakened as of the mid afternoon, suggesting that
the remainder of the evening should be relatively benign, albeit
isolated strong storms south of a line from Kissimmee to

With the HRRR finally catching up to latest trends, have higher
confidence in a brief period of quieting this evening and early
tonight, with rain chances dropping to 20-40% through midnight, and
even lower north of I-4 where skies have already begun to clear in
Marion & Putnam counties. The front will continue its journey
southward this evening and overnight, potentially even reaching near
Lake Okeechobee. However, rain chances will rebound quickly to above
50% just prior to daybreak as additional upper forcing arrives to
FL, expanding eastward from the northern Gulf Coast, and the front
floats back northward. Lows tonight mainly in the mid to upper 60s,
although far northern Lake and Volusia counties may record values in
the upper 50s to lower 60s, feeling an influence of slightly cooler
air behind the front.

Tomorrow...Tuesday looks to be the wettest day of the week, as the
dancing boundary retreats back northward one last time. No change to
expected rainfall, as record PW values over 2.00" continue to pump
along the boundary from the Gulf. Widespread showers with embedded
thunderstorms are anticipated, with a few strong to marginally
severe storms that could produce similar impacts as seen the past
few days. Rainfall totals tomorrow on the order of 1-2",
contributing to the 2-4" totals already received over the last few
days in the area. With the ground becoming more saturated, the
chance for minor flooding becomes enhanced, and thus an increased
flood concern will be present tomorrow, generally south of I-4 and
for areas that have already received multiple rounds of heavy rain.
PoPs tomorrow at an unheard of 80-90% for April, which might be a
little aggressive given trends over the last 48 hours, but
definitely making a dent in the rainfall deficit across the
peninsula. Another day of extensive cloud cover keeping highs
ranging from the mid 70s to lower 80s.

Tuesday Night-Wednesday Night...The lingering frontal boundary
will begin to jog slightly southward Tuesday night, as a
reinforcing cold front pushes into the Southeast. Rain chances
will remain elevated through the overnight, but will finally see
some decreases across northern portions of the area, as PoPs range
from around 30% north of I-4 to 60% along the Treasure Coast. A
couple of thunderstorms will also remain possible. Additional
rainfall amounts of 0.25-1" expected. Morning lows falling into
the 60s.

The reinforcing cold front will cross into northern Florida through
the day on Wednesday, finally forcing the persistent boundary south
of the Florida peninsula. Shower and thunderstorm chances lingering
into Wednesday evening, but will be greatly reduced from the
previous two days. In fact, expecting dry conditions north of I-4,
with chances remaining around 50-60% along the Treasure Coast,
mainly in the morning. PoPs will continue to decrease from north to
south through the day; Then, only a slight chance of showers for
Wednesday night along the southern Treasure Coast. Wednesday
afternoon highs will take advantage of the decreasing cloud cover,
rising into the mid-80s.

Thursday-Saturday(modified previous)...High pressure builds in
across the Southeast U.S. and FL to end the week. Dry conditions
prevail Thursday and Friday, with afternoon highs in the upper 70s
to low 80s. Breezy north winds early on Thursday quickly veer
onshore by Thursday afternoon. Overnight lows settle into the
mid/upper 50s inland and low/mid 60s along the coast. Models are
indicating another front could cross the local area next weekend,
but there are considerable timing and location differences. For now,
have opted to add a 20 percent chance of rain for Saturday.


Generally MVFR/IFR cigs across the area, however the front has
dropped a bit south of KEVB, allowing for cloud breaks this
afternoon for DAB/SFB/LEE. Most SHRA/TSRA activity through 00Z will
concentrate south of MLB, with lingering low clouds persisting
through the overnight. Expect showers to come to an end briefly this
evening into the early morning, ramping up again after 10/12Z. Low
stratus will accompany showers early tomorrow, leading to another
day of widespread MVFR/IFR. Confidence is high in numerous showers
through most of Tue, with lower confidence in exact setup of
thunderstorms thru the TAF period.


Tonight-Tomorrow...Showers and storms will move quickly offshore
from the mainland across the Atlantic waters, generally south of
Cape Canaveral through the remainder of the afternoon and evening.
Activity will redevelop early tomorrow morning, with heavy rain and
potential for gusty winds through most of the day. Position of the
slow moving frontal boundary will cause varying wind direction,
which will shift from onshore in the morning to southeast by the
afternoon, remaining 10-15 knots. Seas 2-3 ft.

Tuesday night-Wednesday night...The persistent boundary continues to
linger into Wednesday morning, bringing high rain chances with
embedded thunderstorms possible. However, a reinforcing cold front
pushing through the Southeast will reach northern Florida Wednesday,
finally forcing the boundary south of the peninsula. Winds will
continue to vary across the local waters, though mostly remaining
around 10 knots or less. Seas 2-3ft.

Thursday-Friday(previous)...High pressure builds across the local
waters, ushering in breezy north winds Thursday morning that become
northeast by the afternoon. A period of hazardous boating conditions
is possible due to the winds, though seas are expected to remain at
2-4 feet. By Friday, winds become east at 10-15 knots with seas 2-3
feet nearshore and 4 feet offshore.


DAB  62  76  63  83 /  30  80  30  10
MCO  65  78  66  84 /  60  90  40  20
MLB  67  81  65  83 /  60  90  60  30
VRB  67  83  66  84 /  60  90  60  40
LEE  64  76  65  83 /  40  80  30  10
SFB  64  77  65  85 /  50  90  30  10
ORL  67  78  67  85 /  50  90  40  10
FPR  66  83  67  84 /  70  90  60  50




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