880
FXUS62 KMLB 271743
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
143 PM EDT Sat Jun 27 2026

...New AVIATION...

.KEY MESSAGES...
Issued at 310 AM EDT Sat Jun 27 2026

- Scattered showers and storms this afternoon and early evening
  will be capable of gusty winds, frequent lightning, and heavy
  downpours. A strong storm cannot be ruled out.

- Lower rain chances overall on Sunday before moisture increases
  early next week as a surface boundary approaches. Rain and storm
  chances increase through Tuesday as a result.

- Hot and muggy conditions persist areawide with peak heat indices
  100-107F each afternoon. A Moderate to Major HeatRisk is
  forecast each day.

&&

.DISCUSSION...
Issued at 310 AM EDT Sat Jun 27 2026

Today-Tonight...Early morning RAP analysis indicates a surface ridge
axis extending from the western Atlantic across central Florida and
into the Gulf. With high pressure overhead, winds remain light and
variable. KMLB radar intermittently shows a few showers moving from
south to north across the Treasure Coast, and even a few blips
between Okeechobee and Osceola counties. The focus for semi-
organized showers (and an isolated lightning strike) will be south
of the Cape and offshore through mid morning. Most inland locations
will stay dry.

Very light southerly flow early on will veer east-southeasterly this
afternoon as the sea breeze forms. A mostly sunny sky this morning
will gradually become partly sunny around/after lunchtime as a
cumulus field builds. If you see darkening cloud bases, there`s a
good chance a shower or storm is not too far off. Storm chances will
increase from the I-95 corridor to points west after 1-2 PM as the
sea breeze advances westward. It may be a bit slower to inch west
along the Volusia coast, so rain chances may linger a couple more
hours there before moving west with the sea breeze. Rain and storm
chances are maximized after 4-6 PM across the interior, including
portions of the I-4 corridor. The environment of ~2000 J/kg MLCAPE,
0-3km lapse rates of 8-8.5C/km (and higher), -7C H5 temps, and DCAPE
close to 1000 J/kg will be in favor of convective development.
However, poor mid level lapse rates, weak flow (negligible bulk
shear), and elevated freezing levels are factors working against
sustained convection. Storm motion will be slow and erratic,
following outflow and sea breeze movement. After 5-6 PM, a west-east
coast sea breeze collision is anticipated, near or just west of the
Orlando metro. Happening right before sunset, this should provide
the greatest coverage of showers and storms before the loss of
daytime heating. Primary hazards from stronger storms include wind
gusts of 40-50 mph, frequent lightning strikes, and brief heavy
downpours. A storm early this evening along the sea breeze collision
could be capable of 50-55+ mph gusts or a brief funnel cloud, but
widespread severe weather is not expected. Some earlier CAMs
suggested outflow-driven pushback of storms toward the Atlantic
coast, but confidence in this occurring is low. Activity largely
dissipates by 9-10 PM with drier conditions into early Sunday.

Temperatures will warm into the low/mid 90s by early afternoon,
sending heat indices into the low 100s at that point. Peak heat
index values are forecast to reach 102 to 107 degrees, and
supporting a Moderate to Major HeatRisk areawide (especially from
northern Osceola/Brevard northward. If you are planning to spend
time outdoors, take plenty of breaks in the shade or A/C and stay
well-hydrated to avoid heat-related fatigue/illness. Never leave
pets or children in vehicles unattended!

Sunday-Monday...H5 ridging becomes more pronounced during this
timeframe, extending from the Gulf to WI/MI and the Great Lakes
region. No real change is expected in terms of surface flow across
our area, starting SSW in the morning and veering onshore in the
afternoon behind the east coast breeze. Modeled QPF is lower overall
on Sunday as forecast soundings show a bit of mid level dry air
entrainment (especially farther south). This results in rain chances
near or slightly below climo (15-25% nearer to the coast / 30-40%
inland). Highs climb a degree or two in response to a bit more
sunshine, but heat indices look fairly similar to today`s forecast
(could be a degree or two higher north of Orlando). Early next week,
a weak trough or surface boundary advances toward north Florida, ans
elongated PVA may boost rain chances along/north of I-4 Monday
afternoon. Moisture increases at the same time with PW 1.9-2.1"+.
This uptick in moisture should support heat indices climbing closer
to the 103-108 range, especially north of I-4. A large portion of
the area is forecast to reach Moderate/Major HeatRisk criteria, as
warm/muggy overnight conditions give little relief to the daytime
heat.

Tuesday-Friday...Slightly above normal rain chances look to continue
Tuesday and Wednesday as the aforementioned trough and perhaps a
brief surface low develops offshore of the NE FL and GA coast. Storm
chances peak during the afternoon and early evening hours with gusty
winds, frequent lightning, and torrential downpours being the main
concerns. Models diverge a bit with regard to available moisture
Thursday onward, so rain chances settle closer to normal toward late
week. In addition, surface flow will become more onshore, carrying
the higher rain chances west of I-95. A slightly stronger east coast
breeze mid to late week means coastal locations could stay closer to
the upper 80s/low 90s for daytime highs, with the low/mid 90s
continuing inland.

&&

.MARINE...
Issued at 310 AM EDT Sat Jun 27 2026

Mainly favorable boating conditions will last this weekend into
next week as light southerly flow turns onshore each afternoon.
Late night/early morning showers and an isolated storm or two
will transition inland during the afternoon hours through Sunday,
though some pushback of evening storms could occur as we get into
early next week. Moisture increases as a surface boundary
approaches Monday-Wednesday, so rain chances increase
(particularly north of the Cape). Winds generally 10-12 kt or
less with seas 2-3 ft through the middle of next week.

&&

.AVIATION...
(18Z TAFs)
Issued at 143 PM EDT Sat Jun 27 2026

East-southeast winds have developed along much of the coast as the
sea breeze has developed. Expect light south winds to shift
southeast across the interior this afternoon as the sea breeze
continues to push inland. Scattered showers and storms should
gradually increase in coverage inland over the next several hours
with TSRA TEMPOs included at SFB (18Z-22Z) and MCO/ISM (19Z-23Z).
Convection moves west of MLB and the Treasure Coast terminals by
21Z/22Z, diminishing by 00Z/01Z at TIX/DAB and the interior
terminals. Light southerly winds often become variable at times
tonight.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  76  93  77  94 /  10  20  10  60
MCO  76  95  77  95 /  30  40  20  60
MLB  78  90  77  92 /  10  20  10  40
VRB  77  91  77  93 /  10  20  10  30
LEE  77  95  79  95 /  20  30  10  60
SFB  77  95  78  96 /  20  30  10  60
ORL  77  94  78  95 /  30  40  10  60
FPR  76  91  76  92 /  10  30  10  30

&&

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

$$

DISCUSSION...Schaper
AVIATION...Law