107
FXUS62 KMLB 010711
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
311 AM EDT Mon Jul 1 2024

...New DISCUSSION, MARINE...

.DISCUSSION...
Issued at 311 AM EDT Mon Jul 1 2024

KEY MESSAGES:

- Increasingly hot this week, peaking by the weekend when the heat
  index could approach 104 to 109 degrees. Residents and visitors
  should consider steps to stay cool during outdoor plans for
  Independence Day through the weekend.

- Scattered showers and storms are forecast each day. The highest
  chances for storms (50-70%) will concentrate over the interior
  and Greater Orlando area, with lesser coverage along the coast.

- Major Hurricane Beryl is approaching the Caribbean this morning
  as the tropics remain unusually active for early July. Beryl,
  and its impacts, are still forecast to stay well south of
  Florida.

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

This evening`s upper-air analysis revealed a nearly 600 dam H5 ridge
near Dallas, TX. Above-normal heights extend across the entire Sun
Belt and into the W Atlantic. A shortwave trough over the eastern
Great Lakes will push a cold front into the Deep South this
afternoon. It will undergo frontolysis before reaching Florida. A
longwave trough near Idaho will work eastward over the next 48 HR,
pushing the upper high closer to Florida by midweek. Ensemble
guidance suggests this upper high will stall near North Florida
through next weekend. This is forecast to protect Florida from any
impacts from Hurricane Beryl, which will be forced WNW through the
Caribbean Sea.

The near-surface ridge axis will be shunted slightly southward today
as the aforementioned front approaches the state. The ridge axis
will slowly return northward by the mid and late week before again
nudging closer to South Florida late next weekend. Near-to-above-
normal PWATs, at times exceeding 2", are forecast through much of
the period. 0-3 KM mixing ratios will also hold steady between 12-14
g/kg, which ranges near the 90th percentile to the max moving
average for early July. This indicates that rich low-level moisture
will remain in place as the south/southeast flow dominates.

In all, this portends a fairly typical rainy-season pattern with
daily scattered showers and storms, focusing over the interior on
most afternoons. With the upper high nudging closer to Florida,
temperatures will turn hotter than normal, introducing a risk of
heat-related health impacts, especially for those outdoors during
the upcoming Independence holiday and weekend.

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

Today & Tonight...

A bit of patchy ground fog is possible through 8 AM. Later on, the
weakening front sagging southward, along with a batch of moisture
across SoFlo, will be the foci for shower and storm coverage. This
is represented well in our digital forecast, with 50-60% storm
chances along the Treasure Coast as well as areas near and north of
Orlando. For Daytona Beach to the Space Coast, storm chances are
lower, closer to 30-40%; this could be generous. As for timing, HREF
members show scattered storms popping along the Treasure Coast after
2 PM. Near Orlando and points north/west, a fairly late sea breeze
collision is expected amid the background southerly flow, so it
wouldn`t be surprising to see storms holding off until after 4-5 PM
and lasting through mid-evening here.

High temperatures will respond to a bit more sunshine and later
storm development, with low/mid 90s fairly common. Peak heat indices
will reach 101-106F in most locations. Lows tonight will fall into
the mid 70s.

Tuesday - Wednesday...

The weak front to our north dissipates but leaves ample moisture
over the state. As the surface ridge axis nudges northward,
background flow will back toward the southeast once again. Scattered
to numerous storms should develop in the afternoon and evening
hours, with coverage of 40-50% near the coast and 60-70% over the
interior and Greater Orlando areas. Coverage may be slightly more
impressive on Tuesday compared to Wednesday as some drier air aloft
tries to work in and we begin to feel additional subsidence from the
upper high. Low to mid 90s will persist, and so will the sultry
humidity. Expect maximum heat index readings to inch slightly higher
(102-107F). Pockets of Major HeatRisk will creep into areas north of
Interstate 4, indicative of unusually hot and humid conditions even
for Florida, and partly driven by overnight low temperatures running
4-7F above normal.

Independence Day - Next Weekend...

Heat-related impacts will drive the weather story for this
timeframe, along with at least scattered (30-60%) storm chances.
Our weather will continue to be dominated by the strong upper
high, characterized by H5 heights exceeding the 95th percentile of
climatology. H85 temperatures rise to around +20C. Boundary layer
flow will remain southeast early in this period before subtly
veering toward the south late in the weekend. This will continue
to draw high humidity out of the tropics, with dew points in the
mid 70s F.

Statistical guidance continues to suggest widespread mid 90s over
the interior and low/mid 90s along the coast. Peak heat indices
are forecast to range from 102-107F for the Fourth of July and
Friday before climbing toward 104-109F next weekend. A Heat
Advisory (108F) may be warranted for at least some of this
timeframe as we get closer in time, especially considering the
number of residents and visitors who will be spending time
outdoors. Planning to enjoy our beaches, attend holiday
celebrations, or visit area attractions? Make sure to pack the
water and sunscreen, and expect to need some time in the shade,
A/C, or pool!

Much of the troposphere will remain warmer than normal, contributing
to relatively poor mid-level lapse rates. Through Saturday, the
southeasterly flow should hold the higher storm chances over the
interior (50-60%), with lesser coverage (30-40%) along the coast.
Storm chances may creep up late in the weekend as the flow veers
southerly and mid-level temperatures dip slightly.

A low pressure system in the tropical Atlantic (Invest 96L)
currently has a 70% chance of development as it moves toward the
Windward Islands late this week. 30/12Z grand ensemble guidance
suggests that the upper high will force this disturbance on a
track similar to Beryl into the Caribbean. However, this will be
something to monitor over the coming days.

&&

.MARINE...
Issued at 311 AM EDT Mon Jul 1 2024

Today-Friday... An axis of high pressure will move from Central
Florida today northward toward the Carolinas by midweek. SSE winds
from 10-15 KT today will subside to around 10 KT while shifting
slightly toward the SE from Tuesday through the rest of the period.
The daily sea/land breeze circulation will form, locally enhancing
breezes in the afternoon and turning winds light southerly or
southwesterly during the overnight hours near the coast. A few
showers and storms are possible, but a lot of dry time is forecast.
Seas will range 2 FT or less through tomorrow, then 2-3 FT through
Friday. Intracoastal and inshore boaters will notice a light to
moderate chop.

&&

.AVIATION...
(06Z TAFs)
Issued at 150 AM EDT Mon Jul 1 2024

VFR and a lot of dry time is expected at sites north of the
Treasure Coast today. SSE winds begin to increase after 15z,
increasing to around 10-12 kt at coastal sites 18z-20z. VCTS
begins 17z, lasting as long as 23z from VRB southward, as the east
coast breeze becomes more active with SHRA/TSRA. Brief MVFR conds
are possible here. A lower-confidence forecast for VCTS exists
from LEE to MCO after 20z-23z. Activity everywhere will wane
after 02z-04z Tue.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  94  77  92  77 /  40  40  40  20
MCO  93  77  93  77 /  50  50  70  20
MLB  91  77  91  78 /  40  30  50  20
VRB  91  75  91  77 /  40  30  50  20
LEE  94  78  94  79 /  60  50  70  20
SFB  94  77  94  77 /  50  50  60  20
ORL  94  77  93  78 /  50  50  70  20
FPR  91  75  91  76 /  50  30  50  20

&&

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

$$

DISCUSSION...Heil
AVIATION...Schaper