158
FXUS62 KMLB 181911
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
311 PM EDT Tue Aug 18 2026

...New KEY MESSAGES, DISCUSSION, MARINE...

.KEY MESSAGES...
Issued at 256 PM EDT Tue Aug 18 2026

- A Heat Advisory is in effect for all east central Florida
  counties until 8 PM for peak heat indices of 108F to 112F.
  Practice heat safety!

- An active weather pattern is forecast through the rest of this
  week, with daily afternoon showers and thunderstorms anticipated
  across east central Florida.

- Hot conditions will continue over the next couple of days, with
  temperatures then trending closer to normal late this week.

&&

.DISCUSSION...
Issued at 256 PM EDT Tue Aug 18 2026

Currently...Outflow produced by storms along the northern Gulf
coast yesterday has traveled to Central Florida and helped get an
early start to showers and lightning storms in the surge of
moisture gradually sagging south across the peninsula. This line
has already pushed through the Orlando Metro and is working
through the southern counties. So far the primary storm hazard has
been frequent cloud to ground lightning and gusts to around 40
mph, but the environment to the south could support stronger
storms.

Rest of Today-Tonight...Offshore (WNW-WSW) flow continues as a
nearly stationary front draped from the Deep South to the Mid
Atlantic seaboard and a broad trough sliding over the eastern US
keep the Bermuda high suppressed. GOES imagery shows a
considerable moisture gradient across the Florida peninsula with
PWATs less than 1.5" (0.5-0.75" below normal) over South Florida
increasing to 2.15" (0.1-0.25" above normal) over North Florida,
and the edge of the 2" PWATs sagging south through Central
Florida. Models have struggled to capture the showers and storms
riding the outflow in the higher moisture, making near storm
environment analysis a challenge, and offering little help with
convective evolution the rest of the afternoon. Earlier storms
weren`t able to live up to their full potential since the early
start meant less instability from daytime heating. However, as the
storms and outflow push south they will move into higher
instability. But then, the drier air to the south will be an
increasingly significant hurdle to deep convection. To further
complicate matters, the offshore flow and outflow has delayed or
even impeded the onshore push of the east coast sea breeze. The
boundary is likely to remain offshore from the Cape north, and may
only be able to make a brief inland push to the south before
storms and outflow arrive. Where the sea breeze can move inland
will be the greatest potential for strong storms with gusts to 55
mph, in addition to frequent cloud to ground lightning and
torrential downpours. Radar shows the boundary has begun a push
near Sebastian inlet. Can`t rule out stronger storms elsewhere,
but chances are lower. Storms and heavy rainfall that get hung up
on the boundary could produce locally heavy rainfall, though
steering flow appears sufficient to keep the risk minimal.

The early rain start has at least provided respite from the heat
for the northern counties where cloud cover remains, with many
sites in and around the Orlando Metro reporting temperatures in
the 80s rather than 90s. Temperatures could get back into the 90s
if skies clear, but will likely fall short of the M-U90s
previously forecast. That said, the rain may spike dew points and
result in some hot, sultry conditions. Areas that don`t get rain,
or where skies clear quickly, are forecast to reach the M-U90s
with peak afternoon heat indices to around 112F, and a Heat
Advisory remains in effect for all of East Central Florida until 8
PM.

Wednesday-Monday (Modified Previous Discussion)...An active
pattern will continue across east central Florida through this
week and into early next week. Mid-level ridging will weaken
across the Florida peninsula, with guidance still developing a
mid-level low over the eastern Gulf/Florida, before getting
absorbed by a trough digging southward across the eastern US this
weekend. At the surface, this mid-level pattern would support
persistent increasing moisture locally, with a series of decaying
frontal boundaries anticipated to approach Florida through late
this week while broad high pressure remains situated across the
Gulf. Locally, west to southwest winds are forecast to continue
areawide, with daytime heating supporting the development of the
east coast sea breeze each day. The push inland during the
afternoon hours will result in winds becoming more south to
southeasterly behind it, with westerly winds aloft preventing too
much intrusion inland. Combined with the moist air mass in place,
a diurnal pattern of showers and storms will persist, with
development driven primarily by the sea breezes each day. Rain and
storm chances will remain near to above normal (40-60%) through
the period, with storm hazards including lightning strikes, gusty
winds, and heavy downpours that have the potential to produce
minor, localized flooding in some spots. With steering flow
remaining out of the west, activity will push offshore through the
afternoon and evening hours each day, with mostly dry conditions
anticipated across the peninsula through the overnight hours.

Temperatures are forecast to remain above normal over the next
couple of days, then the increasing cloud cover and rain chances
will lead to a trend closer to normal late this week and into the
weekend. However, heat will still remain a concern through this
week as high humidity pushes peak heat indices well into triple
digits, with continued support from guidance that some locations
across east central Florida may near and even exceed Heat Advisory
thresholds. This will continue to be closely monitored and
additional heat products will be issued as needed

&&

.MARINE...
Issued at 256 PM EDT Tue Aug 18 2026

Generally favorable boating conditions outside of offshore moving
afternoon/evening storms and heat. Westerly to southwesterly flow
will continue between a front stalled across the Deep South and
high pressure over the Atlantic. Winds shift south the southeast
in the afternoon and evening as the sea breeze develops, which
will be slowed by the offshore flow. Wind speeds outside of storms
10-15 kts. Seas 1-3 ft. Near to slightly above normal lightning
storm chances return as moisture increases. Stronger storms will
be capable of wind gusts 34 kts or greater, frequent cloud to
water lightning, and heavy downpours.

&&

.AVIATION...
(18Z TAFs)
Issued at 139 PM EDT Tue Aug 18 2026

VFR conditions outside of convection through the period. There is
ongoing showers and storms this afternoon. Additional showers and
storms are forecast through the afternoon and early evening hours,
especially along the coast where the sea breeze collision is
forecast to occur. Have included VCTS starting across all the
terminals at 18Z. Have added TEMPOs for MVFR conditions for the
interior sites starting at 18Z for ongoing convection. Have
maintained PROB30 for MVFR conditions for the coastal terminals
starting around 20Z. May need to adjust timing since convection is
starting and moving quicker than expected. Any lingering activity
will push offshore or dissipate after 01Z. Outside of convection,
westerly winds around 10 KT this afternoon with gusts up to 20 KT
will become light this evening. Winds will then pick up to 5-10
KT by 15Z Wednesday.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  78  95  76  94 /  20  50  20  60
MCO  79  95  77  95 /  20  60  20  70
MLB  79  94  78  92 /  20  60  20  50
VRB  77  93  76  92 /  20  50  20  50
LEE  78  95  77  95 /  20  60  20  70
SFB  79  95  77  95 /  20  70  20  70
ORL  80  95  78  95 /  20  60  20  70
FPR  77  93  76  92 /  20  50  20  60

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory until 8 PM EDT this evening for FLZ041-044>046-053-
     058-141-144-154-159-164-247-254-259-264-347-447-547-647-747.

AM...None.
&&

$$

DISCUSSION...Haley
AVIATION...Watson