Roseland, Florida Weather Forecast Discussion

067
FXUS62 KMLB 062355
AFDMLB
Area Forecast Discussion
National Weather Service Melbourne FL
755 PM EDT Sat Sep 6 2025
...New AVIATION...
.KEY MESSAGES...
Issued at 208 PM EDT Sat Sep 6 2025
- High rain and storm chances will continue each day through at
  least the middle of next week.
- There is a low threat for locally heavy rain and minor flooding
  through at least the middle of next week as multiple rounds of
  showers and storms are forecast.
- Peak heat index values reach 100 to 105 this weekend, before
  temperatures trend near to below normal next week.
&&
.PREVIOUS DISCUSSION...
Issued at 208 PM EDT Sat Sep 6 2025
-----------Synoptic Overview-----------
Transient ridging has bridged over the state on this Saturday
afternoon. Courtesy of yet another strong shortwave diving through
the jet stream north of Florida, the persistent trough over the
Great Lakes has been reinvigorated. While the heart of the longwave
trough stays well north of here, ensemble members lend it enough
energy to produce another break in the ridge over the Deep South and
Florida from Sunday through the middle of next week.
The mid-level trough to our north is sending another cold front into
the Southeast U.S. this weekend. It will lose its baroclinic
definition as it reaches Florida and likely becomes stationary. With
the axis of an upper-air weakness holding just west of Florida, the
state should yet again be placed within the right entrance region of
the H2 jet from Monday through at least Thursday. With broad
diffluence contributing to ascent, there is still a cluster of
members that form an area of low pressure by Tuesday or Wednesday
somewhere near Central Florida. Regardless, the proximity of the
front, lift, and anomalously high total moisture over the peninsula
should extend this stretch of unsettled weather for several more
days.
While confidence is extremely low, EPS members amplify the trough
over the Southeast U.S. by late next week in response to unyielding
positive height anomalies over Canada. If this occurs, drier air has
at least a low chance of reaching the district by next Friday or
Saturday. We call it a low chance, for now, as the GEFS/GEPS means
are not as bullish on such a pattern change. If it can get here, any
drier air would likely be temporary as the MJO still looks to become
favorable for ascent and corresponding negative pressure anomalies
in the W Caribbean and Gulf between Sep 15-20.
-----Short-Term Mesoscale Features-----
Mesoanalysis finds a weak surface trough extending roughly from
Tampa to Melbourne, juxtaposed with total moisture (PW) values
greater than 2" south of Interstate 4. The morning sounding from XMR
(06/15Z) measured a PW of 2.2", warm cloud depths to ~ 15 KFT,
moderate instability, and an unusually-low convective temp of 86
deg F. We also have a pair of modest shortwaves to monitor, one of
which is approaching Florida from the Eastern Gulf, with the
other over Louisiana.
On Sunday, weak positive vorticity advection continues from the
slow-moving shortwave currently in the Gulf. More of the area
should be influenced by light southwest flow as the front remains
over the northern portions of Central Florida. A sea breeze from
the Atlantic will try to force its way inland, but will likely
struggle to do so, focusing convergence over the eastern half of
the peninsula. Moisture values should remain unusually high.
-------Sensible Weather & Impacts-------
Now - Tonight...
Much of the district has seen substantial insolation, causing
scattered rain and storms to blossom pretty early today. Eventually,
storms should try to concentrate from Leesburg to Orlando to near
Okeechobee by early evening, with some of this likely to linger past
sunset. Inherited storm chances look good with only minor tweaks,
from 60% at Daytona Beach to 70-80% elsewhere. Gusty winds to
40-45 mph and occasional/frequent lightning can be anticipated in
the strongest storms. Rain chances diminish to less than 30%
overnight.
Still think the highest potential for localized flooding today will
reside from Greater Orlando southward over areas west of I-95. While
not widespread, HREF/REFS members indicate a 5-10% chance of
receiving 3-5" of excessive rainfall. The prototype WPC Urban Rain
Rate Dashboard for Greater Orlando shows a 45% (25%) chance of a 2
(5) year ARI event somewhere in the urban corridor. A 5-year ARI
event often produces minor flooding, especially over suburban/urban
landscapes.
Peak heat indices this afternoon will be uncomfortable in the 100-
105 deg F range.
Sunday...
More unsettled weather with high rain and storm chances (70-80%) by
afternoon and evening. As described in the mesoscale features, we
anticipate the focus of rain and storms to be displaced a bit east
of today and firmly over the eastern half of the peninsula. The
primary hazards remain locally heavy rainfall, gusty winds to around
40-45 mph, and deadly lightning. Storm motions may be hastened just
a bit compared to today, but HREF/REFS members show a 10% chance of
3" rainfall tallies, which could cause minor flooding. Peak heat
indices should top out around 100 degrees.
Next Week...
High moisture, the nearby front, and potential weak low pressure
formation combine to yield a rinse-and-repeat forecast through at
least Thursday. Numerous showers and storms (60-80%) are forecast
each day, with even some activity lingering into the night along the
coast. If an area of low pressure forms, winds may become breezy to
gusty north of the feature, which would deteriorate beach
conditions. There is still much uncertainty, except to say that the
rain gear will need to be handy. Daily storm chances range from 60-
80% Mon-Thu. Excessive rainfall leading to minor flooding will
continue to be a concern, particularly if the heaviest storms keep
occurring over the same locales.
Confidence falls quickly from next Friday and beyond as members
diverge on the upper-air pattern. This requires a continuation of
scattered showers and storms in the forecast until the details
become clearer. Statistical guidance shows brisk onshore winds north
of Cape Canaveral late next week.
Highs in the mid 80s to around 90 deg F are forecast, likely
averaging out a bit below normal due to showers and cloud cover.
&&
.MARINE...
Rounds of showers and storms are likely for the next several days,
with the potential for a few gusty offshore-moving storms,
especially on Sunday. A stationary front sits atop the local
Atlantic this weekend, and is forecast to be reinforced by a
secondary front arriving from the north early in the week.
Prevailing winds and seas remain favorable, however, outside of
storms.
Seas up to 3 FT through Monday, building to 2-4 FT on Tuesday -
Wednesday, except up to 5 FT in the Gulf Stream. Winds south of the
front will be S/SE up to 12 KT, turning E/NE north of Cape
Canaveral. Will monitor a potential freshening of onshore winds over
our northern local waters early next week, particularly if an area
of low pressure can form on the stationary front.
&&
.AVIATION...
(00Z TAFs)
Issued at 724 PM EDT Sat Sep 6 2025
Convection is winding down this evening, with scattered showers
and lightning storms lingering mainly across the interior from
the Orlando Metro area northward. Have VCSH through 03Z for all
terminals. Mostly dry conditions are expected overnight. Winds
will be light tonight, from the south, before becoming southwest
by mid morning and remaining 10 KT or less. The east coast sea
breeze is forecast to form in the afternoon, turning the winds
onshore. Another active day is forecast Sunday, with activity
initially forming along the coast as the sea breeze forms in the
afternoon. Activity will then focus across the interior (generally
west of I-95) into the mid afternoon where boundary interactions
will occur. Have included VCTS starting along the coast at 18Z and
across the interior at 20Z. Any lingering activity is forecast to
dissipate or move out of the area by around 03Z with winds
becoming light and variable.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB  75  88  74  86 /  30  80  60  80
MCO  74  92  75  89 /  60  70  60  80
MLB  76  89  74  88 /  30  80  70  80
VRB  74  90  73  89 /  40  80  70  80
LEE  75  89  74  86 /  60  70  60  70
SFB  76  90  74  87 /  40  80  60  80
ORL  76  90  75  88 /  60  70  60  80
FPR  73  90  71  89 /  40  80  60  80
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
&&
$$
DISCUSSION...Heil
AVIATION...Watson

NWS MLB Office Area Forecast Discussion