812
FXUS62 KMLB 131935
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
335 PM EDT Thu Jun 13 2024

...New DISCUSSION, MARINE...

Key Messages...

-Scattered to numerous showers and storms through this evening,
 with locally heavy rainfall and a few strong storms still
 possible.

-Higher rain chances continue Friday and Saturday, with locally
 heavy rainfall still a concern.

-Rain chances continue, but are forecast to gradually decrease
 into late weekend and next week as winds become onshore and
 breezy.

.DISCUSSION...
Issued at 335 PM EDT Thu Jun 13 2024

Currently-Tonight...Area of low pressure, designated Invest 90L, off
the northeast FL coast will continue to shift slowly northeast into
tonight. Trough extending from this low has shifted southward toward
the Orlando area, with winds out of the N/NE near and north of this
area. While farther south, S/SW flow continues to pull in more
moisture, which led to higher coverage of showers and storms across
Okeechobee County and the Treasure Coast. This activity has
continued to weaken as it shifts eastward and offshore. Farther
north, convection will continue to increase through late afternoon
where greater daytime heating is ongoing. Scattered to numerous
showers and storms will primarily develop along any boundaries,
including the lingering trough axis, the inland moving sea breeze
across Volusia County, and from any differential heating boundaries
generated by the increased cloud cover across southern portions
of the area, and partly sunny skies to the north. Persistent or
repeated rounds of showers and storms will still pose a threat of
heavy rainfall, with totals around 1-3" and locally higher totals
of 4 inches or more possible. Additional storm threats will
include occasional to frequent lightning strikes and strong gusty
winds to 40 to 45 mph.

Scattered showers and storms will linger into the evening, but
gradually diminish by late evening and toward midnight. CAM guidance
indicates fairly dry conditions overnight. However, some
increasing shower/storm potential will occur later tonight toward
daybreak Friday across Okeechobee County and the Treasure Coast.
Remaining mild and humid with lows in the low to mid 70s.

Friday-Saturday...Invest 90L will continue to lift N/NE and remain
offshore the eastern U.S. coast, and may strengthen some through
early this weekend. As it does so, a weak frontal boundary will
shift into northern portions of central FL, and gradually fade into
the weekend. There remains some differences in the models with how
much drier air filters into the north through this period, with the
GFS drier than the ECMWF. Have trended PoPs down to 60-70 percent
into tomorrow, and ranging from 40-50 percent north of Orlando and
60-70 percent south on Saturday. Steering winds weaken and deeper
moisture across southern portions of central FL will keep the
potential for locally heavy rainfall in the forecast. WPC maintains
a Marginal Risk for Excessive Rainfall in the forecast for both
days, especially focused over southern sections of the area. Locally
heavy rainfall of 1-3 inches will be possible with any slow moving
or repeated rounds of showers and storms. Other storm hazards will
continue to be occasional to frequent lightning strikes and gusty
winds.

Afternoon high temperatures forecast to be a little warmer across
northern portions of east central FL both days, with highs in the
low to mid 90s and in the upper 80s to the south. Lingering humid
conditions will lead to peak heat index values around 100-105.
Overnight lows remain in the low to mid 70s.

Sunday-Wednesday...High pressure building off the eastern U.S. coast
will lead to winds becoming onshore and increasing into next week.
This will shift deeper moisture southwest of the area. However,
models continue to be in disagreement through early week, with the
ECM showing higher rain chances than the GFS due to the GFS
showing drier air moving into the area. Therefore some uncertainty
remains in overall rain chances, but have PoPs trending downward
from 50-60 percent on Monday and then around 50 percent Tuesday
through Wednesday. Temperatures will be seasonable through the
period, with afternoon highs in the upper 80s to low 90s, and lows
remaining in the 70s.

&&

.MARINE...
Issued at 335 PM EDT Thu Jun 13 2024

Tonight...Invest 90L off the northeast FL coast will shift slowly
northeast, with a weak trough axis across the northern waters.
This will lead to varying winds out of the N/NW across the Volusia
waters, around 5-10 knots, and out of the W/SW farther south up to
10-15 knots. Seas will range from 1-3 feet. Scattered showers and
storms will continue to be possible, especially across the
Treasure Coast waters into tonight.

Friday-Monday...(Modified Previous Discussion) A weak front will
shift into and remain in place across north central Florida
through Friday and gradually fade into the weekend. Invest 90L is
forecast to continue to move northeast off the eastern US coast.
Winds will be rather variable around 5-10 knots on Friday,
becoming E-SE on Saturday afternoon. Winds will become easterly
and increase to 10-15 knots on Sunday as high pressure exits
offshore of the eastern U.S. coast, and will remain onshore and
increase into early next week with speeds up to 15-20 knots. Seas
2-3ft will increase up to 4 ft in the offshore waters on Monday.
Scattered showers and scattered lightning storms will generally
persist each day, especially across the Gulf Stream waters.


&&

.AVIATION...
(18Z TAFs)
Issued at 109 PM EDT Thu Jun 13 2024

IMPACTS:
-Heavy showers and storms affecting Treasure Coast early/mid
 afternoon today.

-Sporadic showers and storms around Greater Orlando early this
 evening.

-Potential MVFR CIGs for Space/Treasure Coast terminals tonight.

A band of heavy rain and storms, with reduced visibilities to IFR
or less and wind gusts to 35 KT, will affect FPR/SUA through
13/20Z. After that time, redevelopment of a few storms looks
probable around the Orlando area between 13/22Z and 14/01Z.
Overnight, a lull is expected with lowered CIGs especially MLB
and southward. There is even a 20% chance of brief IFR CIGS, but
confidence too low for TAF at this time. Surface trough overhead
will make prevailing winds difficult through early evening:
becoming NE around 10 KT for DAB with VRB/ESE winds at MCO.
Treasure Coast will remain SW 5-15 KT. METARs are not currently
reporting at DAB/FPR due to an outage.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  74  90  74  92 /  40  60  20  40
MCO  75  92  75  91 /  60  60  30  60
MLB  73  89  74  89 /  60  60  40  60
VRB  73  89  72  89 /  60  70  50  70
LEE  76  94  76  95 /  60  60  30  50
SFB  74  92  75  94 /  50  60  30  50
ORL  76  92  75  93 /  50  60  30  60
FPR  72  89  72  89 /  60  70  50  70

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&

$$

DISCUSSION...Weitlich
AVIATION...Heil