260
FXUS62 KMLB 121806
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
206 PM EDT Fri Jul 12 2024

...New DISCUSSION, AVIATION, MARINE...

.DISCUSSION...
Issued at 206 PM EDT Fri Jul 12 2024

KEY MESSAGES:

- Above-normal temperatures are forecast this weekend, with a
  Moderate to Major HeatRisk each afternoon. Those planning to be
  outdoors should take precautions to prevent heat-related
  illness.

- Fairly typical rainy-season weather pattern over the next week,
  with the highest potential for showers and storms inland of
  Interstate 95 including Greater Orlando.

---------Synoptic Overview----------

A weak mid-level trough just east of Florida will lift northeast as
it fills over the next couple of days. In its wake, H5 heights will
build to around 595 to 596 dam by late Saturday, which is
approaching daily record maxima. Throughout the period, flat ridging
will extend from the Desert Southwest to the Bermuda High. 12/00Z
ensemble cluster guidance strongly suggests a trough will push into
the Great Lakes and Ohio Valley by the middle of next week.

A bit of drier air pushed southward down the peninsula today, but
that trend will not last. Near-to-above-normal total moisture will
return this weekend and into next week. Near-surface ridging will
hold near or over Central Florida over the next week, so boundary-
layer winds should remain rather light. Beneath unimpressive mid-
level winds, drivers of daily storm evolution and placement will be
primarily the sea breeze circulation & collision (primarily over the
interior) and resultant outflow boundaries.

------Sensible Weather & Impacts------

This Evening/Tonight...

RAOB analysis indicated PW (total moisture) values as low as 1.63"
on the 12/10Z XMR sounding. Much of this dry air is within the H7 to
H8 layer, drawn southward on the west flank of a weak trough
offshore. This will act to limit lightning storm chances through mid-
evening to 30-40% for many spots. The exception will be a 50-60%
coverage zone across the Osceola, Okeechobee, and Treasure Coast
areas. Already, a few storms are developing over the I-75 corridor;
with westerly steering some of this activity should make it into
those locales. The 12/12Z HREF indicates a low (10-20%) probability
of brief gusty winds exceeding 35 mph in a few of the storms.
Occasional to frequent lightning will also occur.

Quiet conditions are expected overnight with lows in the low/mid 70s.

This Weekend...

What influence the trough offshore had on our weather quickly
fades. High pressure will remain nearby, but with light winds a
daily sea breeze will push inland from both coasts. Moisture will
return from the Atlantic on Saturday and Sunday. Each
afternoon/early evening, this conceptual pattern will result in
35-45% rain/storm chances along the coast, increasing to 60-70%
over the interior (incl. Orlando). For those interior locales,
slow storm motions will provide a 30-40% risk for 2"+ rainfall
tallies in a 60- 90 minute period, which could result in minor
flooding. Gusty winds of 35-45 mph and frequent lightning strikes
will have the potential to accompany the strongest storms. Most of
the overnight and morning hours will be dry.

Temperatures will remain above normal, with low to mid 90s each
afternoon and mid/upper 70s late at night. The hottest readings are
forecast near and north of Greater Orlando. Peak heat indices of 103-
107F will be attained on both afternoons, so the threat of heat-
related illness will continue to be of concern. Remember to check
the back seat for kids and pets, and stay hydrated!

Next Week...

We see no significant changes to the overall setup. Ensemble
guidance continues to show excellent agreement in the large-scale
pattern, which will be dominated by ridging over the southern U.S.
By mid to late next week, a trough is forecast to cross through the
Great Lakes, which may force the ridge a little southward. Depending
on its depth, a minor influence on storm coverage and motions could
result beyond Wednesday, but it`s too early to know for sure.

Surface ridging will stay very close to Central Florida. With near
to at times above normal total moisture (PWATs), expect scattered to
numerous (40-70%) daily afternoon and evening lightning storm
coverage as the sea breezes push inland and collide. It would appear
that the highest coverage will continue to remain over the interior
on most days. Localized minor flooding, gusty winds 35-45 mph, and
frequent lightning remain the primary hazards.

Temperatures will run near or just above normal. Daily highs in the
low/mid 90s and lows well into the 70s will continue, along with
peak heat indices of 100-107F.

&&

.AVIATION...
(18Z TAFs)
Issued at 206 PM EDT Fri Jul 12 2024

Mainly VFR conditions through the TAF period. Confidence where,
when, or if TSRA/SHRA will develop remains lower than normal due to
multiple opposing factors. A weak trough extending across ECFL will
provide a focus for convection, but drier air, subsidence, cloud
cover, and dust will limit potential deep convection. Went ahead and
pulled VCTS from KLEE-KSFB-KDAB where the drier air is moving in to.
Bulk of TSRA/SHRA should stay south of KMCO/KISM and west of KTIX-
KSUA, but chances remain high enough for VC mention, especially the
coastal terminals due to westerly low-level flow which could push
some TSRA/SHRA back to the coast. Mostly dry overnight, then
slightly higher rain chances Saturday as moisture increases. Went
with a conservative start of VCTS at 18Z at this time. In addition,
area of -RA could develop through the period, but should remain VFR.

&&

.MARINE...
Issued at 206 PM EDT Fri Jul 12 2024

A surface ridge axis will maintain its position near or over the
local Atlantic for several days to come, allowing winds to turn SE 5-
12 KT. The daily sea breeze circulation will be unimpeded, with
nearshore winds increasing to ESE 10-15 KT each afternoon. Shower
and storm coverage will be lower over the weekend and into early
next week compared to the past couple of days, but we will keep 30-
40% chances especially at night and in the morning hours. Seas 2-3
FT, except up to around 4 FT in the offshore waters Sunday into
Monday.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  77  93  77  93 /  20  50  10  50
MCO  77  93  78  93 /  40  70  20  70
MLB  76  91  78  91 /  40  40  10  40
VRB  74  92  77  92 /  30  40  10  40
LEE  78  94  78  93 /  30  70  20  70
SFB  77  94  78  93 /  40  70  20  70
ORL  78  94  78  94 /  40  70  20  70
FPR  74  92  76  92 /  30  40  10  40

&&

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

$$

DISCUSSION...Heil
AVIATION...Haley