821
FXUS62 KMLB 051849
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
249 PM EDT Fri Sep 5 2025

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

.KEY MESSAGES...
Issued at 245 PM EDT Fri Sep 5 2025

- Scattered showers and an isolated storm or two through this
  evening; showers lingering at the coast overnight

- Unsettled weather with above normal rain chances expected
  through the weekend and much of next week. The risk for locally
  heavy rainfall could increase by the middle of the week.

- Peak heat index values reach 100 to 105 this weekend, before
  temperatures trend near to below normal next week

&&

.DISCUSSION...
Issued at 245 PM EDT Fri Sep 5 2025

Now-Tonight...A very weak surface boundary/trough remains over
central Florida this afternoon as clouds overspread much of the
south-central FL Peninsula. East-northeasterly flow is occasionally
gusting around 20 mph at the coast, and RAP MSLP analysis shows a
very subtle tightening of the pressure gradient over the local
Atlantic. GOES-derived PW indicates a south-to-north push of
higher moisture content, and as a result, KMLB radar is a bit more
active this afternoon. Bands of scattered showers are ongoing
from Cape Canaveral to Orlando and portions of Osceola County,
surrounded by more isolated activity to the north and south. There
are a few embedded lightning strikes, but moderate to heavy
showers will be the main mode of activity through the evening
(lacking instability and higher lapse rates).

CAM guidance drifts the bulk of activity west of the area by early
evening, but with deeper moisture and persistent onshore flow, rain
chances could linger along the immediate coast through tonight.
Interestingly, NBMEXP guidance does show higher rain probs (up to 60-
70%) near the Cape to Sebastian through early Saturday morning. This
will be something to monitor, especially if training bands of
rainfall set up over the same locations. Localized street flooding
can occur as a result of repeated moderate/heavy rains. Lows
overnight are forecast to settle in the mid 70s.

This Weekend (previous)...A few mid-level shortwaves move through
the persistent broad troughing pattern over the eastern US. The
resident stationary frontal boundary and associated higher moisture
over South Florida lifts north a bit into Central Florida Saturday.
Then, a weakening cold front and its attendant moisture over the
Southeast pushes towards North Florida Sunday, setting the stage for
another period of unsettled weather. Rain chances increase well
above normal across the area, though we do keep a slight gradient of
higher chances (up to 80%) to the south and somewhat lower chances
(up to 60%) across the north until the next front properly arrives.
Instability remains unimpressive, but a few lightning storms capable
of occasional cloud to ground lightning and gusty winds will be
possible.

Temperatures creep up a degree or so Saturday, but remain mostly
around normal with highs in the U80s along the coast and U80-L90s
inland, resulting in peak afternoon heat indices in the U90s-L100s,
approaching the M100s in a few spots Saturday.

Next Week (modified previous)...The pattern stays fairly stagnant
through mid-week, as weak broad troughing remains in place over the
eastern US, weakly stretching across the Southeast. H5 anomalies
favor building heights over the Upper Midwest with continued
eastern CONUS troughing through at least the end of next week.
With little forcing, a weakened front and associated high moisture
sag into Central Florida, becoming stationary once again. Rain
chances remain well above normal as even ensemble mean PWATs come
in at or above the 90th percentile. While overnight showers will
be possible, the highest chances will be focused along the
afternoon sea breezes, as usual. There is potential for a weak low
pressure system or two to develop along the boundary, which would
shift the location of the highest rain chances around, depending
where, when, and if they form. Daytime temperatures remain near to
slightly (a degree or two) below normal in the U80s/L90s,
accompanied by lows in the M70s.

Looking ahead to next weekend, models keep us locked in to a similar
pattern with not much movement in the stalled frontal boundary over
central/south Florida. Additional mid-level energy may gain latitude
and head in our direction from the southeastern Gulf, which would
mainly work to reinforce moisture and higher rain chances over east
central Florida. Ensemble guidance favors near to slightly below
normal temperatures continuing into the third week of September,
aided by additional cloud cover.

&&

.MARINE...
Issued at 245 PM EDT Fri Sep 5 2025

Generally favorable boating conditions are forecast through the
weekend and into early next week, though rain and occasional
lightning storm chances gradually increase each day across the local
Atlantic. Surface flow remains 10-14 kt or less through Sunday,
predominantly onshore during the day and turning offshore at night.
However, the presence of a weak front may make for light/variable
wind directions at times. A second (weakening) cold front is
forecast to approach early next week and effectively stall over the
local Atlantic. Winds increase near the front (around 15 kt), mainly
north of the Cape, through mid to late week. Seas build from Monday
onward, up to 5 ft or so offshore, across the offshore Volusia and
Brevard waters.

&&

.AVIATION...
(18Z TAFs)
Issued at 200 PM EDT Fri Sep 5 2025

Scattered showers are observed across east central Florida early
this afternoon while a frontal boundary remains stalled across
south Florida. VCSH is forecast at all terminals today with the best
coverage from TIX/MCO southward. Have generally limited the
mention of TEMPOs due to short duration for any potential VIS/CIG
terminal impacts. Conditions dry around the greater Orlando
terminals this evening with VCSH persisting overnight along the
coast from TIX southward. East winds increase to 9-12 kts this
afternoon with occasional gusts to around 18 kts. Winds diminish
to 5 kts or less tonight, becoming light and variable at times.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  76  89  75  89 /  20  40  30  50
MCO  76  91  75  91 /  20  60  30  60
MLB  77  89  75  89 /  30  50  30  70
VRB  75  90  74  89 /  40  60  40  70
LEE  75  91  75  91 /  10  50  20  50
SFB  76  91  75  90 /  10  50  20  60
ORL  76  91  75  90 /  10  60  20  60
FPR  74  90  74  89 /  40  60  40  80

&&

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

$$

DISCUSSION...Schaper
AVIATION...Law