552 
FXUS62 KMLB 220917
AFDMLB

Area Forecast Discussion
National Weather Service Melbourne FL
417 AM EST Sun Nov 22 2020

.DISCUSSION...
Today-tonight...A ridge that has been extending towards the
mid-Atlantic states and southeast U.S. in the last few days, it
will finally lift northeast today. This as a low pressure develops
over the Ohio Valley. Locally, the pressure gradient will weaken 
even more, providing for a light wind flow generally from the 
east. Forecast soundings indicate that PWAT will increase to an 
inch and a half today as a bulk of moisture moves over our local 
forecast area. Coastal counties have observed on/off rainfall
earlier this morning, remaining mostly over the coastal counties
as moderate-heavy rain and dissipating quickly as these move to
the west of I-95. A few lightning strikes were spotted over the
waters. As the day progresses, the activity will focus towards
Brevard/Osceola northward and with the mid levels flow from the
south, activity will move towards Orange/Seminole. Mention of
thunder was included as limited instability will be present as the
cap between 850-700 mb erodes this morning. As showers/lightning
storms start to decrease in coverage around sunset, interior areas
should dry out this evening follow by coastal areas after late
evening. With a focus of showers north from Indian River
northward, I don't expect minor flooding concerns for St Lucie and
Martin counties.

High temperatures will reach near 80 this afternoon, followed by a
drop to the mid-upper 60s tonight. Due to a persistent swell 
still reaching the local waters, a high risk for rip currents 
continues today for the local beaches. 

Monday-Wednesday...A mid-level trough pushing from the Ohio Valley 
into the Northeast states will drag a weak, dry surface cool front 
through east central Florida on Monday. Winds becoming northerly by 
sunrise on Monday, with breezy conditions returning mainly to the 
coast and the Atlantic waters. The front will pass through the local 
area through the afternoon, ushering in much drier air. Models 
suggest PWATs falling to as low as 0.6" Monday into Tuesday, with a 
slight rebound through mid week, but remaining well below 1". 
Forecast soundings also include a strong, very dry subsidence 
inversion above 850mb (though extending even lower at times, 
especially initially after the frontal passage). Thus, have no 
mentionable PoPs in the forecast through Wednesday, with the 
exception of a small area ~20% over the Atlantic waters as the front 
sags southward Monday. High pressure over the eastern US will not 
linger long before pushing eastward into the Atlantic ahead of the 
next low pressure system. Winds veering back to onshore Tuesday into 
Wednesday. Winds will remain breezy along the coast and offshore 
into Tuesday night, as the pressure gradient remains tight with the 
building high pressure. But, winds will decrease along with the 
gradient on Wednesday. 

Afternoon high temperatures remaining in the upper 70s to low 80s 
each day. Low temperatures will cool behind the front Tuesday 
morning, dropping into the upper 50s north of I-4, with mid to upper 
60s along the immediate Treasure and southern Space Coasts. Dew 
points will be a bit more pleasant to start the week, in the upper 
50s to low 60s.

Thursday onward...Later in the week, models develop a slightly 
stronger area of low pressure over the central plains before pushing 
this feature through the Ohio Valley. A cold front dropping through 
the Deep South looks to stall over north Florida before dissipating. 
Winds will take on a more southerly component as the front 
approaches the area, becoming SE Wednesday night into the day on 
Thursday. However, winds will return to easterly late Thursday as 
the front diffuses. Have no mentionable PoPs through the end of the 
week at this time. However, some light PoPs could return to the 
forecast if the subsidence inversion breaks down sufficiently, which 
is low confidence at this time. Temperatures warming slightly into 
the lower 80s, with morning lows in the low to mid 60s.

Isolated PoPs return late next weekend, ahead of yet another 
approaching frontal boundary.

&&

.AVIATION...
SHRA will continue this morning and early afternoon reaching the 
coastal terminals, reducing visibilities to 1-3SM and cigs to 
1-3kft. Less coverage of SHRA after mid-afternoon for coastal
terminals from KMLB to KSUA. Area of low stratus will continue
streaming southwest and keep cigs at 5 kft over KLEE and at times
for KDAB, KSFB, KMCO, and KISM. For interior terminals, SHRA
reaching them this morning are in light intensity and dissipating
as they continue to move westward, leaving KLEE rain-less.
However, by late morning, coverage of SHRA will increase inland,
with some small probabilities for TSRA. Impacts from these will be
an occasional lightning strike and heavy rain, reducing
visibilities. Winds will prevail from the east at 8-15 kt with
brief gusts to 20-25 kt in the heavier storms.

&&

.MARINE...
Today-tonight...Winds will continue to decrease today as seas due
the same thing. However, 7 feet seas were still being observed at
buoy 41009 and 8 ft at 41010, the Small Craft Advisory was
extended for the nearshore waters of Brevard and Treasure Coast
through 10 am. Outer waters advisory remains through this evening.
These could be adjusted as new observations come in today. So even
for areas without an advisory, caution will need to be exercise as
seas will be up to 6 ft. Showers and isolated lightning are
expected today, producing localized higher seas and winds. 

Monday-Tuesday...A trough passing eastward through the Ohio Valley 
into the Northeast will drag a weak, dry cool front through ECFL on 
Monday. Hazardous boating conditions returning as winds veer N and 
increase to 15-20kts again. These wind speeds will persist through 
Tuesday; However, winds will veer back onshore by Tuesday afternoon. 
Seas 5-6ft, building up to 7ft offshore by Monday afternoon. A 
slight chance of showers possible offshore during the frontal 
passage on Monday, otherwise dry conditions expected.

Wednesday-Thursday...Winds diminish Wednesday, as the high pressure 
over the eastern US pushes into the western Atlantic and the 
pressure gradient eases. Speeds becoming 10-15kts Wednesday, then 
10kts or less on Thursday. Onshore flow will veer SE Wednesday then 
nearly S Wednesday night as another front approaches ECFL, but 
stalls across northern FL before dissipating. Seas diminishing along 
with the winds, becoming 5-6ft Wednesday afternoon, then 3-5ft 
Thursday. Dry conditions are expected to continue.

&&

.HYDROLOGY...
The Saint Johns River at Astor is forecast to remain in Minor Flood 
Stage through at least middle of next week. Forecast details are 
available on the daily River Flood Statement issued by NWS Melbourne 
until further notice.

&&

.PRELIMINARY POINT TEMPS/POPS...
DAB  79  65  76  60 /  40  20   0   0 
MCO  81  65  80  60 /  40  20   0   0 
MLB  80  68  79  64 /  40  20  10   0 
VRB  81  68  80  66 /  40  20  10   0 
LEE  81  64  79  58 /  40  20   0   0 
SFB  81  65  79  59 /  40  20   0   0 
ORL  81  67  80  61 /  40  20   0   0 
FPR  80  67  79  65 /  40  20  10  10 

&&

.MLB WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...Small Craft Advisory until 10 AM EST this morning for Sebastian 
     Inlet to Jupiter Inlet 0-20 nm-Volusia-Brevard County Line 
     to Sebastian Inlet 0-20 nm.

     Small Craft Advisory until 4 PM EST this afternoon for Flagler 
     Beach to Volusia-Brevard County Line 20-60 nm-Sebastian 
     Inlet to Jupiter Inlet 20-60 nm-Volusia-Brevard County Line 
     to Sebastian Inlet 20-60 nm.

&&

$$

Negron/Leahy