Heathrow, Florida Weather Forecast Discussion

615
FXUS62 KMLB 071822
AFDMLB
Area Forecast Discussion
National Weather Service Melbourne FL
222 PM EDT Sun Sep 7 2025
...New KEY MESSAGES, DISCUSSION, MARINE, AVIATION...
.KEY MESSAGES...
Issued at 1253 PM EDT Sun Sep 7 2025
- Unsettled conditions persist through at least mid week as deep
  moisture enhances coverage of afternoon showers and storms.
- There is a low threat for locally heavy rainfall and minor
  flooding as multiple rounds of showers and storms are forecast.
- Peak heat index values reach 98 to 104 today, before
  temperatures trend near to below normal through the rest of the
  week.
&&
.DISCUSSION...
Issued at 1253 PM EDT Sun Sep 7 2025
Deep moisture remains pooled over the peninsula this hour. This
morning`s sounding, along with GOES derived precipitable water,
paints a picture of a fairly saturated atmosphere, with PWATs
approaching their climatological max for this time of year
(2.1-2.2"). Strong solar insolation and convective temps in the
mid to upper 80s allowed for another early start to showers and
storms, particularly across the Treasure Coast.
Light west steering flow aloft suggests showers and storms, and
their attendant boundaries, will pile up over the eastern half of
the peninsula from mid to late afternoon. The only fly in the
ointment that may counteract the otherwise wet/unstable atmosphere
is mid/upper level debris moving off the convective complex over
the eastern Gulf. This is liable to impact coverage across
northern areas (I-4 corridor) where surface heating gets
disrupted. Still, ingredients are there for scattered to numerous
convection, so rain chances of 60-70% have been maintained.
Light offshore steering flow should push storms into the Atlantic
after sunset, though a few lingering showers can`t be ruled out
through midnight.
Conditions don`t change appreciably for the start of the workweek
as the local area remains at the base of a mid and upper level
trough over the eastern US coast. Broad, albeit weak, forcing
should maintain lower pressures over the eastern Gulf and western
Atlantic, with any surface features expected to remain generally
disorganized. Meanwhile, a weak front will meander closer to the
area through the period, allowing winds to turn onshore more
readily especially near and north of the Cape. All of this
portends continued unsettled conditions, with rain chances above
climatology (60 - 80%) through at least Wednesday. A low excessive
rainfall risk persists across the same time frame, especially in
areas that see multiple rounds of heavier rain in storms. Should
low pressure manage to form nearby along the front, will watch for
local enhancement to onshore flow and any attendant enhancement
to coastal rain chances.
Late in the week, confidence lessens a bit as models and their
ensembles show differences in the handling of shortwave energy
over the southeast. While the ECMWF and some of its members bring
considerably drier air into the area (albeit temporarily), the
GFS/GEFs are less enthusiastic with continued moist onshore flow.
For this forecast package, continued trend of lessening PoPs
across northern areas, especially NW of I-4. Regardless, guidance
shows brisk onshore winds north of Cape Canaveral late next week.
&&
.MARINE...
Issued at 1253 PM EDT Sun Sep 7 2025
Today-Monday...Generally favorable boating conditions (outside of
higher than usual coverage of thunderstorms) given variable winds
at or below 10 knots, enhanced locally by the afternoon east
coast sea breeze. Seas around 2 feet.
Tuesday-Thursday...A stationary front will shift southward into
the local waters. Onshore flow will develop to the north of the
boundary (particularly from around Cape Canaveral northward) and
increase up to 10-15 knots at times. Weak low pressure may develop
along the front - potentially freshening winds for a period. Seas
expected to build to 2-4 feet due to an increasing northeast
swell, up to 5 feet in the Gulf Stream.
&&
.AVIATION...
(18Z TAFs)
Issued at 1253 PM EDT Sun Sep 7 2025
Eastward moving showers are observed across portions of central
Florida early this afternoon, and there is some uncertainty in how
convection will evolve through the remainder of the day. Generally
expecting a wet pattern with VCSH/VCTS at all terminals.
TSRA TEMPOs are included along the coast from MLB southward starting
at 18/19Z as a broken line of showers/storms approaches from the
west and collides with the sea breeze. Some clearing is forecast for
most of theses terminals generally after 20Z with VCTS/VCSH
remaining for activity west of MLB and the Treasure Coast. Across
the interior, showers and storms are forecast to increase in
coverage late this afternoon as boundary interactions increase, but
building cloud cover has introduced uncertainty. Have held the
inherited TSRA TEMPOs (20Z/23Z) steady across the interior, and will
continue to monitor and adjust with amendments as needed. Widespread
coverage diminishes early this evening while showers and a localized
storm could linger a few hours beyond sunset. West to southwest
winds turn southeast to east with the sea breeze, remaining 10 kts
or less. Winds mostly light and variable overnight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB  75  85  74  85 /  50  70  60  80
MCO  74  88  73  89 /  50  80  50  80
MLB  74  87  74  87 /  60  70  60  80
VRB  73  89  73  89 /  60  70  60  80
LEE  74  86  73  86 /  50  80  50  80
SFB  75  86  73  86 /  50  80  60  80
ORL  74  87  73  88 /  50  80  50  80
FPR  72  89  72  89 /  60  70  60  80
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
DISCUSSION...Ulrich
AVIATION...Law

NWS MLB Office Area Forecast Discussion