Area Forecast Discussion
Issued by NWS Melbourne, FL

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS62 KMLB 250136

Area Forecast Discussion
National Weather Service Melbourne FL
935 PM EDT Sun May 24 2020


...Flood Watches Across the South Will go Into Effect Farther
North Monday Morning...

...Heavy Rain and Localized Flooding Expected Through Memorial Day...

Surface trough associated with NE flank of tropical wave extends
across the FL Keys into SOFL this evening. This feature is drifting
northward on the eastern side of a large/broad, negative tilt mid-
upper trough covering the GOMEX.

Statewide radar mosaic shows mainly light rain and sprinkles thus
far across the northern half CWA, patchy over the north, becoming
more widespread/moderate south of Melbourne/Kenansville. Numerous to
widespread showers and a few embedded were noted, lurking offshore

For the remainder of tonight, the inverted surface trough will
continue to lift north toward lake Okeechobee and the Treasure
coast by sunrise Memorial Day. Meanwhile, large scale ascent will
increase markedly as a H50 vortlobe lifts northward over the
peninsula, accompanied by strong H25 divergent ascent. This should
result in a significant increase in coverage of rain late tonight,
with embedded convection developing, especially offshore/along the
Treasure Coast. Periods of heavy rainfall expected to develop with
increase in nighttime flooding potential late.

Current disparate POP distribution ranging from slight chance far
north to categorical far south looks to have a good handle on
expected trends. No changes to the forecast.


.AVIATION...Prevailing MVFR CIGs/areas light rain will spread
northward across the SUA-MLB corridor overnight, then through the
remainder of the aerodromes after 12Z, with areas to prevailing
IFR CIGs MCO-TIX southward, through 00Z.


.MARINE...Per local buoy/C-Man data, E to ESE winds near 15kt north
with seas 4-5ft north of SIPF1, 15-20kt/5-6ft to the south. Status
quo expected to continue through sunrise, with increase in coverage
of marine storms south, some of which could become strong late. No
changes to the current forecast or SCEC.




.Prev Discussion... /issued 424 PM EDT Sun May 24 2020/

Tonight...Deep tropical moisture will continue to stream northward
across east central FL through the overnight hours with low level ESE
flow in the H9-H8 layer increasing to 25-30 knots. This will allow
convergent bands to continue to move onshore mainly south of
Sebastian Inlet through the overnight. A Flood Watch has been issued
for Okeechobee/Martin and St Lucie counties starting at 4 pm with
risk of heavy rainfall into the evening and then another increase in
shower bands moving onshore late tonight along the Treasure Coast.
From Orlando northward expect a lower shower coverage overnight in
the scattered range with the heavier rain threat reaching Orlando on
Memorial Day. Lows in the lower to mid 70s.

Memorial Day...The mid level trough approaching from the west,
diffluent and divergent flow aloft and a copious amount of tropical
moisture (PWATS to 2.2-2.4 inches) will lead to heavy rain bands
setting up across the area on Monday. The tropical wave axis lifting
north across the area will lead to low level convergence which will
focus very heavy rainfall bands initially along the Treasure Coast
in the morning and then lifting up into Brevard/Osceola and metro
Orlando by afternoon. There is a risk of training rain bands in the
strengthening low level southeast flow. Areal rainfall amounts will
reach 2 to 5 inches across east central FL with isolated maximum
amounts up to 8 to 10 inches in a few locations. The higher amounts
would likely set up along the Brevard and Treasure Coast with
coastal convergence and rain bands continuing to train and stream
onshore. SPC has placed southern portions of east central FL in a
marginal risk for severe weather with curved low level hodographs
favoring the potential for some rotating storms that could produce a
brief tornado. High temps will be held down to around 80 with the
cloud cover and heavy rainfall.

Tue-Wed...High rain chances will continue Tue to 70-80 percent and
then dropping to 50-60 percent Wednesday. The deep moisture will
begin to push off into the Atlantic on Tuesday push leave a trailing
band of moisture near the coast with the highest tropical moisture
along the Treasure Coast. SSW low level flow will favor the eastern
side of the peninsula for a high coverage of afternoon showers and
storms with the heavy rainfall threat continuing across east central
FL, especially along the coastal counties. THe flow will relax
somewhat Wed but with southerly flow and deep moisture rain chances
will remain above normal with the east coast breeze pushing inland
by late afternoon and triggering additional convection. Highs in the
mid/upper 80s will rise to the upper 80s to around 90 on Wed.

Thursday-Saturday (Previous)...The remnants of the vigorous tropical
wave will be somewhere near the GA/SC coastline as a strong surface
high builds into the western Atlantic. Some of the deep moisture
lingers, keeping our rain chances on the high side Thursday and
Friday. Scattered to numerous showers/storms could develop each
afternoon. By Saturday, as the ridge axis finally moves atop the
Florida peninsula and the deep tropical moisture is filtered out,
rain chances return to normal values around 30-40 percent.
Temperatures look to be near normal, as afternoon highs reach the
mid 80s along the coast and upper 80s inland.


Showers this afternoon, mainly along the Treasure Coast
(KSUA/KFPR/KVRB). Will need to be watched this afternoon for
embedded thunderstorm development and VCTS. RA/SHRA is expected to
taper off by around 00Z. Then, a brief dry period for much of the
overnight, before increasing showers for the whole east central
Florida area late tonight. Widespread -RA/RA expected by tomorrow
afternoon, beginning along the Treasure Coast in the early morning.
CIG/VIS reductions to MVFR are likely in heavier showers today, then
affecting more northern terminals tomorrow.


Tonight...E/SE winds to 15/15-20 knots will keep seas elevated
across the Atlantic. Will continue Small Craft Exercise Caution
headlines south of Sebastian Inlet with the highest coverage of
shower and isolated storms also expected across the southern waters
overnight. Seas mainly 4-5 ft.

Monday-Thursday...A strong tropical wave will move across the
Florida peninsula and local waters during the early part of the
upcoming week. Heavy rainfall is increasingly likely, with a chance
of thunderstorms each day from Monday through Wednesday. Boating
conditions could become poor to hazardous Monday as southeast winds
increase to 20 knots and seas build 5-6 feet. There is a chance some
storms Monday could be strong, producing wind gusts in excess of 35
knots and waterspouts.

By Tuesday, seas diminish to 4 feet and south winds drop to 10-15
knots. By mid week, conditions improve as high pressure builds into
the area late week. Still, deep moisture allows scattered to
numerous showers and storms to develop each afternoon Wednesday and


DAB  73  80  70  85 /  20  90  70  80
MCO  72  81  71  88 /  40 100  70  80
MLB  75  81  72  86 /  50 100  70  80
VRB  74  81  72  87 /  60 100  70  80
LEE  72  81  70  87 /  30  90  60  70
SFB  71  81  70  88 /  30 100  70  80
ORL  72  80  71  87 /  30 100  70  80
FPR  74  81  72  87 /  60 100  70  80


FL...Flood Watch through Monday evening for Martin-Okeechobee-St.

     Flood Watch from Monday morning through Monday evening for
     Indian River-Northern Brevard-Orange-Osceola-Seminole-
     Southern Brevard.



Volkmer/Combs/Leahy is the U.S. government's official web portal to all federal, state and local government web resources and services.