758
FXUS62 KMLB 121744
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
144 PM EDT Sat Jul 12 2025

...New AVIATION...

.KEY MESSAGES...
Issued at 330 AM EDT Sat Jul 12 2025

- Hot and humid today, peak heat index values 102 to 107 degrees;
  residents and visitors are encouraged to stay cool and well-
  hydrated to avoid heat-related illness

- Isolated to scattered storms mid to late afternoon, primarily
  west of Interstate 95; gusty winds, frequent lightning, and
  torrential rainfall are possible

- Deep moisture moves over central Florida Sunday into next week,
  promoting above-normal rain and lightning storm chances,
  especially each afternoon/evening

&&

.PREVIOUS DISCUSSION...
Issued at 330 AM EDT Sat Jul 12 2025

Today-Tonight...A pressure ridge axis remains loosely draped across
south-central Florida this morning. Clearing is taking place over
the northern locations while a few mid level clouds remain across
the Treasure Coast. Conditions feel rather warm and muggy everywhere
with temps in the upper 70s to near 80 degrees and dew points in the
mid 70s.

With high pressure still influencing our overall pattern, winds will
remain light through the day. A WSW wind direction swings SE along
the immediate coast from midday into the early afternoon as the east
coast breeze develops. The breeze may end up a little more well
defined from the Cape northward. Regardless, CAMs keep it pinned to
the coast until mid/late afternoon, when it is forecast to collide
with the west coast breeze west of Interstate 95. Shower and storm
coverage will be isolated at best until then.

The highest rain chances exist from the Orlando metro to Lake
Kissimmee and Okeechobee late in the afternoon, with weak
northerly steering flow carrying storms southward. Forecast
sounding profiles feature very steep low-level lapse rates, -8C H5
temps, 2"+ PW, and 1000+ J/kg DCAPE. Thus, updraft development
should be very quick. However, keeping these sustained with very
little bulk shear will be a challenge. As storms collapse (quickly
in many cases), water- loaded downdrafts will be capable of
producing wind gusts in excess of 45 to 50 mph. Small hail cannot
be ruled out but is low probability. Frequent lightning strikes
and torrential rainfall leading to localized flooding are the
remaining hazards to look for from today`s storms. Activity will
gradually wane after 9-10 PM with clearing conditions overnight
and temperatures settling back into the mid 70s.

Outside of any rain, most locations are forecast to warm into the
low/mid 90s. Combined with higher humidity, peak heat index
values will approach 102 to 107 degrees this afternoon. A Moderate
to Major HeatRisk exists, especially from Orlando/Titusville
northward. This level of heat can affect most anyone, even when
spending short periods of time outdoors. Take care to stay well
hydrated and cooled to avoid heat-related illness, and remember to
never leave pets or children unattended in a hot vehicle!

Sunday-Monday...The eastern side of a H5 pressure ridge begins to
erode on Sunday with the northern jet stream situated well north of
Florida. A weak disturbance rotates around the high and across the
central Florida Atlantic coast Sunday afternoon. Despite slightly
warmer H5 temps, the disturbance may provide additional upper level
support to convection. PW getting close to daily maximums in some
spots (2.1+") means the "skinny CAPE" look to sounding profiles
returns. This indicates a moisture-laden environment capable of
producing greater shower and lightning storm coverage.
Additionally, the threat of localized flooding will increase,
especially on Monday, as broad low pressure forms over the
peninsula. Total QPF from various ensemble output does not appear
overly impressive as of the latest 00z runs, but several members
in each of the EC-AIFS, EC, GEFS, and CMC suites do point to
heavier amounts (2-3"+) across the southern half of the area by
Tuesday morning. Once CAM guidance is within range, we could have
a better look at what locally higher totals may be tomorrow and
Monday. A few strong storms with gusty winds and frequent
lightning also cannot be ruled out, as waterlogged downdrafts
collapse and occasionally produce 40-50 mph gusts.

Temperatures will remain quite warm on Sunday (90s) with heat index
values ranging from 101 to 106. However, increasing coverage of
storms and cloud cover will provide relief by mid to late afternoon.
On Monday, forecast highs drop another degree or two, reaching the
upper 80s (coast) to low 90s (inland). High rain chances will put a
cap on any higher temps to start the week.

Tuesday-Friday...A surface trough is forecast to extend from the
Carolina coast to the Florida Nature Coast Tuesday morning, in
addition to a couple of mid level energy impulses over north and
south Florida. High rain and storm coverage is anticipated to
continue Tuesday, with the highest chances (80%) focused west of
I-95. Model discrepancies are introduced as early as Wednesday,
when questions arise pertaining to 500mb steering flow and the
development of a mid level high over the western Atlantic. Still,
high PW will remain over the peninsula, supporting 60%+ rain and
storm chances through Thursday. Daytime temperatures slide closer
to normal for mid July, only peaking in the upper 80s to around 90
degrees. Low pressure retrogrades westward, then northwestward
across the Gulf mid to late week. With it goes the better support
for widespread rain chances, so this forecast keeps rain chances
in the 50-60% range from Friday onward. Rain chances will not go
away, but moreso resemble the typical sea breeze convective
pattern by next weekend.

&&

.MARINE...
Issued at 330 AM EDT Sat Jul 12 2025

Favorable boating conditions persist in the absence of heavy rain
and lightning storms. Weak high pressure will linger over Florida
and the adjacent Atlantic waters through a portion of Sunday before
a trough of low pressure begins to develop later Sunday into early
next week. High atmospheric moisture will support greater coverage
of showers and lightning storms through at least the first half of
next week. Weak WSW surface flow, which briefly veers SE this
afternoon and Sunday afternoon, weakens further on Monday. SE flow
around 10-15 kt returns Tuesday-Wednesday. Seas remain fairly steady
state (except locally higher in storms) through Tuesday, around
2-3 ft. Seas may climb closer to 3-4 ft offshore late Wednesday as
SE flow strengthens and high pressure builds.

&&

.AVIATION...
(18Z TAFs)
Issued at 131 PM EDT Sat Jul 12 2025

A line of storms on the west coast of Florida is steadily moving
eastward this afternoon. Have moved up the time for VCTS for LEE
to start at 18Z, and ISM to start at 19Z to account for these
storms moving in from the west. May need to move up the VCTS
timing for MCO, but there remains some uncertainty due to model
guidance indicating convection will die as it reaches ECFL. So
will monitor and amend as necessary. Have maintained the TEMPOs
for MCO/ISM, but confidence is not high this will materialize.
VCTS for the rest of the terminals this afternoon, starting from
18-22Z. Convection will diminish around sunset (23-01Z), with
winds becoming light and variable overnight. W/WNW winds will
increase to 5-8KT by mid- morning on Sunday before backing
onshore along the coast in the afternoon with the sea breeze.
Scattered showers and storms are once again forecast for Sunday
afternoon, with VCTS starting at MCO around 20Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  76  92  75  91 /  30  70  30  60
MCO  76  94  75  93 /  20  70  40  80
MLB  75  91  74  88 /  20  70  40  70
VRB  73  91  72  89 /  20  70  50  70
LEE  77  93  76  92 /  20  70  40  80
SFB  77  94  76  93 /  20  70  40  70
ORL  77  94  76  92 /  20  70  40  80
FPR  74  91  72  88 /  30  70  50  70

&&

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

$$

DISCUSSION...Schaper
AVIATION...Watson