732
FXUS62 KMLB 181756
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
156 PM EDT Fri Sep 18 2026

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

.KEY MESSAGES...
Issued at 155 PM EDT Fri Sep 18 2026

- A passing disturbance aloft will help generate scattered to
  numerous showers and storms across the area through this weekend
  and into next week.

- A few stronger storms will be possible this afternoon and
  evening, with the main threats being strong wind gusts up to 50
  mph, frequent lightning, small hail and locally heavy downpours
  of 1-3 inches.

- Seasonable temperatures will continue across the area over the
  next several days.

&&

.DISCUSSION...
Issued at 155 PM EDT Fri Sep 18 2026

Through Tonight...A mid/upper level low drifting westward towards
the Florida peninsula from the Atlantic has made it to east
central Florida, with GOES19 visible satellite imagery showing a
broad counter-clockwise rotation of some upper level clouds. This
is further supported by SPC upper level analysis, with the 12Z
analysis indicating the center of the upper level low was just
offshore. This set-up has brought increasing moisture to the area,
with the dry air mass in the mid-levels slowly being eroded away
as seen in the observed sounding. Temperatures aloft have also
cooled a few degrees down to around -10C today as a result of the
low, as indicated by the 10Z XMR sounding. This set-up combined
with persistent east- northeast flow at the surface has allowed
for isolated to scattered showers and storms to develop across the
Atlantic waters this morning and into the early afternoon hours,
with the diffuse east coast sea breeze supporting further
development across parts of the Florida peninsula this afternoon.
Continued development of showers and storms is forecast through
the remainder of this afternoon, though lingering dry air between
800-500mb has served as a limiting factor for more robust
development across the area. This trend will likely continue, with
hi-res guidance continuing to favor lower coverage of activity
through the rest of today. Trended rain and storm chances slightly
below NBM through this afternoon, with the highest coverage of
activity anticipated across the Treasure Coast and near Lake
Okeechobee over the next few hours (40-50%). Given the cold
temperatures aloft and pocket of lingering dry air in the mid-
levels, some isolated stronger storms cannot be ruled out across
east central Florida this afternoon. Storm hazards will include
frequent lightning strikes, wind gusts up to 50 mph, small hail,
and heavy rainfall that leads to quick accumulations of 1-3".
While activity is anticipated to wane into the overnight hours,
the increasing moisture combined with persistent onshore flow will
continue to support isolated shower and storm development across
the local Atlantic waters through the overnight hours, with some
activity potentially moving onshore along the east coast.

Afternoon high temperatures remain on track to range between the
mid 80s to low 90s, with the warmest temperatures anticipated
across the far interior northwest of I-4. Tonight, temperatures
will remain near normal values for this time of year, falling into
the low to mid 70s. A moderate rip current risk persists at the
local beaches.

Saturday-Sunday...The mid/upper level low will continue to drift
westward from east central Florida towards the western Florida
peninsula and the eastern Gulf through Saturday, with the feature
becoming quasi-stationary on Sunday. This set-up will help keep a
moist air mass overhead through the weekend, with PWATs forecast
to range between 1.8-2" on Saturday and exceed 2" areawide on
Sunday. This moisture combined with persistent northeast flow will
support isolated shower development early in the mornings across
the local Atlantic waters, with activity drifting onshore.
Coverage is then anticipated to increase into the afternoon hours
as a diffuse east coast sea breeze develops and moves inland, with
scattered to numerous showers and storms each day. Some drier air
aloft may help limit coverage on Saturday, so have continued to
trend slightly below NBM values based on hi-res guidance. Sunday,
higher coverage of showers is anticipated due to the increasing
moisture. Isolated to scattered storm development is anticipated
with activity, especially during the afternoon hours. The low
overhead combined with daytime heating will create sufficient
instability across east central Florida, further supported by cold
-8C to -7C 500 mb temperatures. These parameters combined with
the 1.8-2.0"+ PWATs indicate that primary storm hazards will
include frequent lightning strikes, wind gusts up to 50 mph, and
heavy downpours producing quick rainfall accumulations of 1-3".
Small hail also cannot be fully ruled out given the cooler
temperatures aloft, but there remains some uncertainty with this.
Shower and storm activity will gradually diminish across the
peninsula each evening into the overnight hours, with the
potential for continued westward-moving shower and storm
development across the local Atlantic waters. Temperatures are
forecast to remain seasonable in the upper 80s to low 90s each
day, with lows in the low to mid 70s each night.

Monday-Thursday...The mid/upper level low will meander across the
eastern Gulf into early next week before lifting northeastward
and weakening as it is absorbed by a trough pushing across the
eastern US. Moist air will remain in place across the Florida
peninsula, with higher rain and storm chances persisting through
next week, especially given an approaching cold front that is
anticipated to drift towards east central Florida mid to late
week. Stronger storms cannot be ruled out at times with this
activity, with lightning, gusty winds, and heavy downpours all
possible. Each night, activity will gradually diminish across the
Florida peninsula with ongoing development across the local
Atlantic waters. Temperatures are forecast to remain near to
slightly above normal through the extended forecast period, with
humid conditions potentially pushing heat indices above 100F once
again in some spots early next week.

&&

.MARINE...
Issued at 155 PM EDT Fri Sep 18 2026

Broad, weak surface high pressure will overspread the local
Atlantic waters through this weekend, resulting in east-northeast
winds remaining around 10 knots this weekend into next week. Seas
are anticipated to continue a gradual decline, starting around 3
to 4 feet through the remainder of today and tonight and then
subsiding to around 2 to 3 feet through the remainder of the
forecast period. While boating conditions are forecast to remain
favorable through the period, the primary hazard to mariners will
be rounds of showers and storms. A moist air mass will promote
continued development of isolated to scattered showers and storms,
with storms capable of producing lightning strikes, wind gusts in
excess of 30 knots, and heavy downpours. Small hail also cannot
be ruled out in stronger storms, though confidence in this remains
low. Activity is anticipated to be persistent, continuing through
the daytime and nighttime hours most days.

&&

.AVIATION...
(18Z TAFs)
Issued at 146 PM EDT Fri Sep 18 2026

VFR conditions are forecast outside of showers/lightning storms
with onshore flow. TAFs begin with VCTS at KMCO/KISM/KFPR/KSUA
with TEMPO groups for TSRA between 18Z-22Z at KFPR and KSUA, as
well as TEMPO groups for MVFR CIGs at KTIX between 18Z-20Z. VCTS
and TEMPO groups for TSRA are forecast at KMCO at 16Z SAT. Breezy
ENE winds are expected to weaken tonight before increasing SAT AM.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  75  88  74  88 /  10  30  30  50
MCO  73  90  73  90 /  10  50  10  70
MLB  76  88  75  87 /  20  40  30  70
VRB  73  87  72  87 /  20  50  20  70
LEE  73  90  73  89 /  10  30  10  70
SFB  73  88  73  88 /  10  40  20  70
ORL  74  89  74  89 /  10  40  10  70
FPR  73  88  72  87 /  20  50  20  70

&&

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

$$

DISCUSSION...Tollefsen
AVIATION...Fehling