489
FXUS62 KMLB 131811
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
211 PM EDT Sun Jul 13 2025

...New AVIATION...

.KEY MESSAGES...
Issued at 310 AM EDT Sun Jul 13 2025

- A disturbance and associated deep moisture moves over central
  Florida early this week. Above-normal lightning storm chances
  and locally heavy rainfall with be the primary impacts.

- High daily rain chances up to around 80% are expected through
  mid week.

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

&&

.PREVIOUS DISCUSSION...
Issued at 310 AM EDT Sun Jul 13 2025

Today... A moisture boundary slides southeastward into central
Florida along a broad surface trough. Building moisture should allow
for another day of diurnally driven showers and storms with coverage
peaking around 70-80 percent in the afternoon and evening. Shear
profiles remain weak with light steering flow out of the north-
northwest. This should favor a southward propagation of showers and
storms along a developing sea breeze, but increasing outflow
boundaries could still allow for slow and erratic storm motions. A
localized flooding rainfall threat exists today with storm total
accumulations of 2-4" possible. Heavy rainfall over short periods of
time could cause ponding of water on area roadways and minor
flooding of urban or low lying areas. While mid level storm
parameters remain modest, steep low level lapse rates, and boundary
collisions could allow for frequent lightning strikes and localized
wind gusts of 45-55 mph. Brief funnel clouds cannot be ruled out as
storms develop along the sea breeze.

High temperatures climb in to the low to mid 90s ahead of shower and
storm development. Combined with increasing humidity, peak heat
index values are forecast to range 102-107 degrees, and a Minor to
Moderate HeatRisk will exist. This level of heat affects most
individuals sensitive to heat, especially those without effective
cooling and/or adequate hydration.

Monday-Tuesday... A weak 500mb trough moves across the southwest
Atlantic Monday, passing over the Florida peninsula on Tuesday. A
broad surface trough offshore the southeast U.S. coast attempts to
become more organized with passing mid level support, developing a
weak low in vicinity of Florida. Waves of anomalously high moisture
move through the region each day with modeled PWATs as high as
2.1-2.2", and values range above the 90th climatological
percentile. High moisture in vicinity of weak mid level support
will continue to fuel high rain chances each day (~80%), and a
heavy rainfall threat will remain present. While global ensemble
guidance suggests daily areawide totals of 0.5-1.5", localized
totals of 2-4" remain in play both days. Areas that receive these
localized higher totals over multiple days will become vulnerable
to ponding of water and minor flooding. Although increased cloud
cover may limit surface instability, tall skinny CAPE profiles
around 2,000 J/kg and vorticity aloft suggest at least an isolated
strong storm threat. Stronger storms will be capable of
occasional to frequent lightning strikes and water loaded
downdrafts which can produce localized gusty winds.

Temperatures trend a few degrees cooler Monday and Tuesday,
corresponding to higher rain chances. Highs in the upper 80s to low
90s Monday range the mid to upper 80s by Tuesday. Morning low
temperatures hold steady in the low to mid 70s.

Wednesday-Saturday... The weak area of low pressure is nudged into
the Gulf on Wednesday as the Atlantic high builds back toward
Florida. As the low pressure departs westward, the National
Hurricane Center has highlighted a 20% chance of tropical
development into the middle to late part of the week. Regardless
of development deep moisture remains in place on the east side of
the feature, keeping high rain chances through mid week (70-80%).
By late week and into the weekend, the Atlantic ridge axis takes
control, favoring a more typical summertime pattern with rain
chances trending closer to normal.

&&

.MARINE...
Issued at 310 AM EDT Sun Jul 13 2025

A broad trough of low pressure moves across the local Atlantic
waters early this week. Increased moisture in vicinity of this
feature will keep high daily rain chances (~60-80%) into midweek.
Light offshore flow backs south to southeast today and Monday as
the east coast sea breeze develops. Southerly flow then develops
from Tuesday onwards as the Atlantic ridge axis begins to
gradually rebuild over the local waters. Seas around 2 ft. Locally
higher winds and seas in vicinity of thunderstorms.

&&

.AVIATION...
(18Z TAFs)
Issued at 140 PM EDT Sun Jul 13 2025

Scattered showers and storms have pushed in from the west and is
currently moving towards DAB. Latest CAMs show a couple rounds of
convection today, with the first round happening now and
continuing into late afternoon with the sea breeze, and the
second coming into early evening as the trough moves southward.
Have maintained afternoon TEMPOS with MVFR conditions for TSRA
this afternoon, starting 20/21Z across the interior, and 18/19Z
along the coast, as well as the secondary TEMPOs for this evening
for ISM and LEE starting at 00Z. Convection will diminish first
along the coast around sunset, and then across the interior around
05Z. Light and variable winds overnight will become WNW and
increase to 5-8KT by mid morning. Cams are showing scattered
showers pushing down from the north Monday morning, so have
included VCSH starting at 14Z for interior TAFs. Scattered
lightning storms will then form in the afternoon, so have included
VCTS for MCO starting at 18Z.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  74  91  75  88 /  50  60  30  70
MCO  75  92  75  89 /  60  80  40  80
MLB  74  88  75  87 /  60  70  40  80
VRB  72  88  72  88 /  70  80  50  80
LEE  76  92  75  90 /  60  80  40  80
SFB  76  92  75  90 /  60  80  30  80
ORL  76  92  75  90 /  60  80  40  80
FPR  72  88  72  87 /  70  80  50  80

&&

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

$$

DISCUSSION...Law
AVIATION...Watson