195
FXUS62 KMLB 170851
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
451 AM EDT Tue Sep 17 2024

...New DISCUSSION, MARINE, HYDROLOGY...

.DISCUSSION...
Issued at 451 AM EDT Tue Sep 17 2024

Key Messages:

- A marginal risk for isolated severe storms exists across all of
east central Florida today.

- Poor to hazardous boating and surf conditions continue today.

- High astronomical tides will promote elevated water levels this
week, and a Coastal Flood Advisory continues through at least
tonight.


Current-Tonight... High cloud cover is in place across much of east
central Florida this morning while observing stations indicate
localized areas of lower stratus. Patchy fog remains forecast across
the interior, hinting at visibility reductions where clouds lower. A
few showers continue in vicinity of Lake Okeechobee while lightning
has remained over the local Atlantic waters.

A weak surface boundary across the southern half of the peninsula
gradually lifts northward late today into tonight. Aloft, a mid
level shortwave swings across the area. Scattered diurnal showers
and storms are forecast as surface heating and boundary interactions
occur. Model soundings suggest steep low level lapse rates this
afternoon which will be supportive of quick strengthening storm
updrafts. An isolated marginal threat exists where updrafts can
interact with dry air and shortwave energy aloft. However, it is
worth noting some uncertainty in the forecast. Continued broken
cloud cover and occasional light showers are forecast to continue
across the south where the greatest moisture exists. This could
delay or limit surface heating where CAMs generally suggest the
greatest convective coverage should occur. An isolated severe storm
which can develop will be capable of localized damaging wind gusts
up to 60 mph, frequent lightning strikes, and torrential downpours.
Westerly steering flow will push convective coverage back towards
the coast late this afternoon and into the evening.

Hazardous beach and coastal conditions continue today. Long period
swells around 9-10 seconds will promote a a high risk of life
threatening rip currents at all area beaches. Additionally,
astronomical high tides will continue a minor coastal flood threat
through at least this evening`s high tide cycle.

High temperatures remain near seasonal in the upper 80s to low 90s.
Peak heat index values are forecast between 98-105.


Wednesday-Thursday... Mid level low pressure across the southeast
U.S. becomes an open trough into Thursday. A surface boundary
continues to lift northward Wednesday, shifting back southward
across the area on Thursday. Local boundary interactions and pulses
of shortwave energy aloft should support scattered afternoon and
evening convection (40-50%) across much of east central Florida each
day. Slightly higher coverage of showers and storms (~60%) is
forecast across Okeechobee and the Treasure Coast in vicinity of
higher moisture. Westward steering flow should allow inland
convection to push back toward the coast each evening. Dry air aloft
could promote isolated wind gusts up to 50 mph where stronger
convective mixing can occur. Otherwise, hazards associated with
isolated stronger storms include occasional to frequent lightning
strikes and locally heavy downpours. Temperatures mostly in the low
90s Wednesday fall a few degrees cooler on Thursday, ranging the
upper 80s to near 90. Peak heat index values are forecast between
98-103 degrees.


Friday-Monday...A 500mb vorticity boundary slides southeastward
across the state late week as mid level troughing moves offshore the
eastern seaboard. A surface boundary settles across south Florida as
high pressure builds across the southeast U.S. The greatest moisture
remains southward late week into early next week. However, scattered
PoPs remain in the forecast each day as sustained onshore flow
develops. Seasonal temperatures are forecast each afternoon ranging
the upper 80s to near 90.

&&

.MARINE...
Issued at 451 AM EDT Tue Sep 17 2024

Today-Tonight...Hazardous seas up to 7 ft offshore gradually subside
through late morning, and a Small Craft Advisory remains in effect
through 11 AM. Otherwise, small craft should exercise caution this
morning for seas up to 6 ft across nearshore Brevard and the nearshore
Treasure Coast. Seas become widely 4-5 ft late tonight. Winds
remain light and variable, developing an onshore component near
the coast as the sea breeze develops. Scattered offshore moving
showers and storms are forecast into the afternoon and evening. An
isolated severe storm will be possible, producing wind gusts up
to 34 kts.

Wednesday-Saturday...Seas continue to subside Wednesday becoming 3-4
ft. Winds remain light and variable before becoming onshore into
late week. Scattered to numerous showers and scattered lightning
storms are forecast through the period.

&&

.HYDROLOGY...
Issued at 451 AM EDT Tue Sep 17 2024

The Saint Johns River near Astor is forecast to remain in Moderate
Flood stage (around 3.2-3.4 ft) through this week. The potential
exists for small additional rises if locally heavy rainfall develops
over the river basin.

Southward, additional heavy rainfall across the Saint Johns River
basin has caused a steady rise in river levels with the forecast
point at Deland forecast to remain in Action Stage and the point at
Sanford forecast to reach Action Stage today. Geneva Above Lake
Harney is now forecast to remain just below Action Stage. Additional
heavy rain could cause further rises, so interests along the river
should monitor for forecast updates.

&&

.AVIATION...
(06Z TAFs)
Issued at 120 AM EDT Tue Sep 17 2024

Will monitor for patchy fog/low stratus (low confidence) development
overnight and early Tue morning, otherwise continued mainly VFR
outside of afternoon/evening convection ~ MVFR CIGs/VSBYs. Should
any fog/stratus develop, expect burn-off by around mid-morning. Some
"Vicinity" wording in place for later convection and will
accommodate TEMPO groups later on as necessary. Appears greatest
convective coverage may be south of KMCO. Light/variable winds
will transition onshore in the afternoon as the sea breeze
develops and pushes well inland by late in the day. Storm steering
flow today will be toward the ENE at 10-15 kts.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  87  73  91  73 /  30  10  40  30
MCO  91  75  92  74 /  50  10  50  30
MLB  89  75  90  74 /  50  20  40  40
VRB  91  73  91  73 /  50  30  50  40
LEE  89  74  91  74 /  40  10  50  20
SFB  89  73  91  74 /  50  10  50  30
ORL  91  75  92  75 /  50  10  50  30
FPR  91  73  91  73 /  50  20  60  40

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Coastal Flood Advisory until midnight EDT tonight for FLZ141-154-
     159-164-347-447-647-747.

AM...Small Craft Advisory until 11 AM EDT this morning for AMZ570-572-
     575.

&&

$$

DISCUSSION...Law
AVIATION...Sedlock