Area Forecast Discussion
Issued by NWS Melbourne, FL

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466
FXUS62 KMLB 161425
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
1025 AM EDT Thu May 16 2024

.UPDATE...
Issued at 1015 AM EDT Thu May 16 2024

Weak frontal boundary has sagged into central FL and will become
stationary across southern sections this afternoon. GOES-16 Total
Precip water product shows much drier air has filtered in across
northern sections with a band of much higher PWAT across southern
FA. Northern sections will experience lower dewpoints/humidity
and mostly sunny skies with max temps in the low to mid 90s.
Higher moisture across the south will promote scattered to
showers and storms this afternoon streaming west to east,
primarily affecting Martin/St Lucie counties. Expect a sea breeze
to develop this afternoon which will add low level convergence to
an already unstable mid levels characterized by steep lapse
rates. Expect an increase in convective coverage and intensity
this afternoon into the early eve. Isolated strong to severe
storms with hail and strong wind gusts will be possible over
Okeechobee, St Lucie and Martin counties. The sea breeze will
provide locally enhanced helicity in the low levels so a brief
tornado/waterspout will be possible in storms along or behind the
sea breeze.

&&

.AVIATION...
(12Z TAFs)
Issued at 1015 AM EDT Thu May 16 2024

A weak frontal boundary will become stationary across central FL
this aftn and tonight. Drier air and clearing sky conditions at
DAB/LEE/SFB/MCO but scattered SHRA/TSRA will stream eastward and
affect SUA/FPR and possibly VRB. Utilizing VC term there but
TEMPOs for MVFR/IFR TSRA will be possible later in the day.
West wind 10-15 knots will dominate then a wind shift out of the
E/SE should occur at coastal terminals (MLB-SUA) aft 18Z. Model
trends will be monitored for patchy fog development early Fri
morning.

&&

.PREVIOUS DISCUSSION...
Issued at 400 AM EDT Thu May 16 2024

Today-Tonight...Activity on radar this morning is largely
confined to the adjacent Atlantic waters, where isolated showers
and a few storms have developed. Across east-central Florida,
mostly dry conditions are present with temperatures in the mid to
upper 70s. A weak cold front is now bisecting the area and will
continue to meander south toward Lake Okeechobee and the Treasure
Coast by this afternoon. North of the front, dry air will be
pushing in from the north. It is along and south of the front
where the highest rain chances will exist (30-50 PoP), especially
this afternoon, along with the chance for a few lightning storms.
Some of the high resolution CAMs are lackluster in relation to
convective activity later today. Thus, NBM guidance was regarded
as too aggressive and high chance PoPs across the Treasure Coast
seemed most reasonable for today. With that said, any storm that
becomes established will have the potential to produce gusty
winds and small hail. The Storm Prediction Center has placed areas
near and south of Fort Pierce to Okeechobee under a Marginal Risk
for severe storms today.

Sky conditions will gradually clear out from north to south behind
the front, allowing locations around the Orlando metro and points
north to warm into the low 90s. A handful of suburban/urban sites
here may even reach the mid 90s by mid to late afternoon. Farther
south, remaining clouds and rain chances will keep temperatures
in the upper 80s to around 90 degrees. Winds become light and
variable tonight, and there are subtle hints in the guidance for
some overnight fog into Friday morning. However, more confidence
will be needed to add fog into the forecast, so model trends will
be monitored through the day. Temperatures late tonight are
forecast to fall toward normal mid-May values, into the mid to
upper 60s.

Friday-Saturday...Low pressure remains in place offshore the mid
Atlantic/ northeast coast Friday and Saturday. An associated
moisture boundary stretches from the western Atlantic into the
northern Gulf, draped across the southern peninsula Friday morning.
The boundary gradually lifts northward through the day Friday,
washing out as high pressure builds at the surface and aloft. A late
afternoon sea breeze collision could support isolated showers and
lightning storms on Friday with PoPs only ranging 10-20 percent.
Uncertainty exists in the PoP forecast Saturday due to model
disagreements in available moisture. The GFS (PWAT ~ 1.6) promotes a
drier solution compared to the ECMWF (PWAT ~ 1.9). The current
forecast follows closer to a GFS solution and has nudged PoPs down
slightly, now ranging 30-40 percent on Saturday. Dry air aloft due
to ridging should limit convective growth, keeping any developing
activity shallow.

Temperatures are forecast above seasonal values through the end of
the week. Highs range the low 90s along the immediate coast on
Friday, warming into the mid 90s across the interior. A few upper
90s cannot be ruled out in vicinity of Lake Okeechobee. Temperatures
warm a degree or two into Saturday.

Sunday-Thursday...Mid level troughing and its associated surface
feature dig across the southeast U.S. early next week, moving into
the western Atlantic. Moisture increases ahead of a cold front
passage Sunday night into Monday. Coverage of showers and storms
builds on Sunday ahead of the cold front with PoPs increasing to
around 60 percent across much of east central Florida. Chances for
showers and storms then gradually dwindle each day with only an
isolated mention Wednesday and Thursday. Afternoon temperatures are
forecast to range the low to mid 90s Sunday and Monday, falling to
range the upper 80s to low 90s Tuesday. Highs widely range the 90s
again by Thursday.

&&

.MARINE...
Issued at 400 AM EDT Thu May 16 2024

Today-Tonight...Favorable boating conditions are forecast outside
of scattered showers and lightning storms. A frontal boundary
draped across the Atlantic will sink south of Sebastian Inlet
later this afternoon, confining higher rain chances to the
adjacent Treasure Coast waters. West-northwest winds 10-15 kt
decrease and turn out of the east-southeast late afternoon and
early evening. Seas 2-3 ft this morning, becoming 1-2 ft this
afternoon and evening.

Friday-Monday...Coverage of showers and lightning storms increases
into the weekend as a cold front approaches the waters on Sunday.
Southerly winds around 10-15 kts veer southwest Saturday night,
becoming northerly on Monday behind the cold front. Seas of 2-3 ft
increase to 4-5 ft offshore Sunday night.

&&

.FIRE WEATHER...
Issued at 400 AM EDT Thu May 16 2024

Today...Drier air is forecast to move into northern and interior
portions of east central Florida later today. As a result,
relative humidity values may fall into the mid to upper 30s.
West-northwest winds will remain around or below 10 mph for a
majority of the afternoon. Additional fire starts cannot be ruled
out from Okeechobee to the Treasure Coast due to a chance for
lightning storms.

Extended...Moisture and storm chances build into the weekend as a
cold front approaches east central Florida on Sunday. Min RH values
ranging the upper 30s to low 40s across the interior increase into
the upper 40s to mid 50s ahead of the front. Drier air builds early
next week, returning interior RHs to the low to mid 40s. Light
southwest flow backs south-southeast as the east coast sea breeze
develops Friday and Saturday. Winds increase to 10-15 mph on Sunday,
veering north-northeast into Monday.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  90  68  91  73 /   0   0  10   0
MCO  92  69  95  75 /   0   0  20   0
MLB  90  69  91  74 /  10   0  20  10
VRB  91  70  93  73 /  30   0  20  10
LEE  91  70  94  75 /   0   0  10   0
SFB  93  69  95  74 /   0   0  10   0
ORL  92  70  95  75 /   0   0  20   0
FPR  91  69  93  73 /  40  10  20  10

&&

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

&&

$$

UPDATE...Kelly