311
FXUS62 KMLB 091132
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
732 AM EDT Sun Jun 9 2024

...New AVIATION...

.AVIATION...
(12Z TAFs)
Issued at 732 AM EDT Sun Jun 9 2024

No significant changes from the 06Z package. VFR conditions
prevail outside of convection. Just ISO TSRA/SHRA expected
along the sea breezes, the sea breeze collision, and TSRA outflow
boundaries, which should mostly stay west and south of the
terminals, but chances for TSRA impacts high enough at all ECFL
terminals except KDAB/KSFB/KLEE for VCTS. Coverage/confidence too
low for TEMPOs, but can`t rule out a short-fused AMD if a
terminal gets unlucky. Light WNW-WSW winds once again favor a
diffuse WCSB, forecast to reach KLEE ~17Z and increase winds to
5-10 kts. ECSB reaches the coastal terminals between 16Z-20Z,
earliest to the south, shifting winds initially ESE ~10kts then
veering to SE-SSE at 10-15 kts with occasional gusts to 20 kts by
around 22Z. Sea breeze collision forecast near KSFB and near or
east of KMCO/KISM ~23Z-00Z. Winds 10 kts or less after 02Z,
veering to SW late tonight.

&&

.PREVIOUS DISCUSSION...
Issued at 450 AM EDT Sun Jun 9 2024

Key Messages:

-Heat Advisory from 11 AM to 6 PM for portions of east central
 Florida

-Record high temperatures forecast today and Monday, including Leesburg
 and Sanford

-High rain chances arrive by mid to late week, repeated rounds of heavy
 rainfall with localized flooding possible

Today-Tonight...Another warm start is underway with temperatures
in the upper 70s to low 80s early this morning. A moisture
gradient is bisecting the area with PW around 1.35" to 1.50" north
of Orlando to 1.80" farther south. The main story for today is
going to be the heat, which has prompted a Heat Advisory for
portions of Brevard and Orange counties south to Okeechobee
County. Along the coast, the afternoon sea breeze will work to
knock temperatures down a few degrees, so heat indices there will
approach but fall just short of advisory criteria. In addition,
drier air north of I-4 will keep heat indices largely below
criteria. High temperatures reaching the mid to upper 90s will be
common most everywhere, with several sites like Leesburg and
Sanford forecast to tie previous record highs. Widespread heat
indices of 102 to 107 are expected with values up to 110 in the
advisory area.

If planning to be outdoors today, even for a short
periods of time, make sure to stay well hydrated and take
frequent breaks in shaded or air-conditioned spaces. This level of
heat can affect anyone without adequate hydration and effective
cooling. Remember to never leave children or pets behind in
vehicles!

Afternoon to early evening rain and isolated lightning storm
chances will be largely confined to locations surrounding Lake
Okeechobee and the Treasure Coast. PoPs were kept near 40-50
percent there, with only a slight chance of a stray shower or
storm from Orlando and Cape Canaveral to the Melbourne area.
Warmer temps aloft will work to limit overall lightning activity.
Outside of any isolated storms, winds may briefly gust behind the
inland push of the sea breeze. At the beaches, a moderate risk
for rip currents is present.

Temperatures will decrease slowly tonight, backing down into the
mid 70s by sunrise Monday.

Monday-Tuesday...A significant shift in the prolonged hot and dry
weather pattern will commence early in the week with increasing
rain and storm chances, especially from Orlando and Melbourne
southward on Monday. Mid level ridging, slightly warmer 500mb
temps, and relatively drier air hold across northern locations
Monday afternoon, keeping the highest PoPs (50-70 percent) focused
south. Model soundings depict appreciable moisture (2"+ PW),
supportive lapse rates, and a backed low-level wind profile along
the coast. One limiting factor to stronger storms may be marginal
500mb temps, but there does appear to be a non-zero risk of a few
strong storms Monday afternoon. The east coast breeze will likely
stay pinned farther east, with storms forming nearer to the coast
and drifting offshore through the early evening. Temperatures will
reach the upper 90s north of Orlando with the remainder of the
area reaching the low to mid 90s. Heat indices may again approach
108 degrees in a few spots, but it remains to be seen whether
coverage will be high enough to warrant an advisory.

A weak cool front is forecast to approach north Florida on
Tuesday as high pressure builds of the Mid Mississippi and Ohio
Valleys. The slightly more dominant west-southwest surface flow
will again keep the east coast breeze stuck near and east of I-95.
With PW approaching and eclipsing 2" over much of the area,
scattered to numerous showers and embedded lightning storms are
forecast Tuesday afternoon and evening. Repeated episodes of heavy
downpours could produce a quick 0.50" to 1.50" of rainfall in any
given location. 48-hour QPF from Monday through Wednesday morning
ranges from 2" to 3" from Melbourne southward, and 0.50" to 1.50"
near and north of I-4. Resultant afternoon temperatures will only
be able to reach the upper 80s to low 90s, due to increased cloud
cover. Lows remain steadily in the low to mid 70s each night.

Wednesday-Saturday...Significant rain chances become established
mid to late week as tropical moisture anchors across the FL
peninsula. This moisture will push daily PWs toward
climatological maximums. The threat for heavy rainfall and
localized flooding goes up as a result, and the Weather Prediction
Center has placed much of the area in a Marginal Risk for
excessive rainfall Wednesday and Thursday. Successive rounds of
moderate to heavy rain and isolated storms will be maximized
during the daytime hours but could also linger through the
nighttime hours. With time for the forecast to be further refined,
the current Wed-Sat QPF places a wide swath of 3" to 5" over
central FL with locally higher amounts possible. If realized, this
would certainly help the present drought conditions. Afternoon
highs will be limited to the 80s with the coolest days being
Thursday and Friday. South-southeasterly winds may also turn
breezy Friday into Saturday as low-level winds increase. Model
guidance is in less agreement toward the latter half of the
weekend, but some flavor of rain chances may linger into Sunday as
well. Overall, it is shaping up to be a rather wet stretch of
days, from Wednesday onward.

&&

.MARINE...
Issued at 450 AM EDT Sun Jun 9 2024

Today-Tonight...Westerly winds back to the southeast this
afternoon behind the east coast breeze (10-15 kt). Winds veer
again to the SSW tonight and approach 17-18 kt over the Gulf
Stream, before decreasing toward daybreak Monday. Isolated showers
and lightning storms are possible, mainly south of Cape Canaveral
and Sebastian Inlet. Seas 1-2 ft.

Monday-Thursday...Increasing moisture, especially from Tuesday
onward, will lead to higher rain and isolated storm chances into
mid week. On Monday, SW winds back to the SSE behind the sea
breeze, increasing and veering SSW again Monday night (especially
over the Gulf Stream). More persistent SSW flow on Tuesday will
back to the SSE by Wednesday and Thursday. Repeated rounds of
moderate to heavy rainfall are expected mid to late week. Boating
conditions deteriorate due to high rain and storm chances, though
seas outside of storms will generally remain 2-3 ft.

&&

.FIRE WEATHER...
Issued at 450 AM EDT Sun Jun 9 2024

Continued fire sensitive conditions are forecast today through at
least Monday, as above normal temperatures and overall dry
conditions remain. Only isolated showers and storms are expected
from near Lake Okeechobee to the Treasure Coast this afternoon.
Relative humidity values will fall into the mid to upper 30s
north of Interstate 4. Additionally, a Heat Advisory is in effect
for portions of east central Florida this afternoon.

A gradual improvement to fire weather conditions is expected
through the week as moisture and subsequent rain chances
significantly increase by mid to late week. However, lightning
strikes may lead to additional fire starts.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  97  74  96  74 /  10   0  40  40
MCO  97  76  95  76 /  20  10  60  50
MLB  93  76  93  75 /  30  10  70  50
VRB  93  75  93  74 /  30  20  70  60
LEE  98  75  96  76 /  10  10  40  40
SFB  99  75  97  75 /  10  10  50  40
ORL  98  76  96  76 /  20  10  50  40
FPR  93  75  93  74 /  30  20  70  60

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...Heat Advisory from 11 AM this morning to 6 PM EDT this evening
     for FLZ045-053-058-247-254-259-347-547-647.

AM...None.
&&

$$

DISCUSSION...Schaper
AVIATION...Haley