Area Forecast Discussion
Issued by NWS Melbourne, FL
FXUS62 KMLB 250919
Area Forecast Discussion
National Weather Service Melbourne FL
519 AM EDT Sat Mar 25 2017
...Poor to hazardous boating conditions continue today...
...High Rip Current threat at the Atlantic beaches today...
Today/Tonight...Mean layer ridging stretched over the Peninsula is
being squeezed by two closed lows, the first over the central Plains
and the other over the Bahamas. Neither of these lows are expected
to exert influence on the local weather pattern today, with high
pressure to our north maintaining E/SE flow and mainly rain-free
conditions. Available moisture (PWATs) remains at or below 1.00":
low enough to keep measurable precip out of the forecast, though a
few convergent bands moving in off the Atlantic could lead to brief
sprinkles/light rain over a small portion of the coast into the
afternoon. Pressure gradient will slacken through the afternoon, so
not expecting it to be as breezy today. This will weaken the marine
influence and allow temps to climb a few degrees relative to Friday:
low 80s inland, upper 70s-near 80 along/east of I-95.
Combined seas of 5 to 7 feet over the nearshore waters and east
winds up to 15 mph will continue to produce choppy to rough surf
along the Atlantic beaches. A high risk for rip currents also
continues today and residents/visitors are reminded to heed the
advice of lifeguards as well as beach patrol flags and signs.
Sunday...High pressure ridge to the north will nose southwest
across the area. The resulting lighter wind flow will allow both
east and west coast sea breezes to develop with a collision late
in the day on the west side of the peninsula, just west of Lake
county. Aloft, a deep cut-off low over IL/IN will have a trough
axis extending south into the Gulf of Mexico. This trough axis and
assocd spoke of vorticity is forecast to weaken as it approaches
the FL peninsula but it may provide enough support to generate
isolated showers over the far interior late in the day when the
boundary collision occurs. The GFS MOS PoPs of 40-50 percent look
too high but compromised with the much lower NAM and ECM MOS and
added 20 PoP for Lake county. Do not have enough confidence to add
thunder given the weak lapse rates and precip water values of
1.25 inches but this may need to be reconsidered with subsequent
model runs. Highs will be in the upper 70s coast and up to the mid
80s inland under partly cloudy skies.
Mon-Fri...Weather looks rather tranquil as low level ridge settles
over the area and a weak front pushes offshore to the north Wed.
As a result, rain chances will remain low through Thu. With no
significant frontal passages or intrusions of cool air, high
temperatures will be above normal in the low 80s coast and mid 80s
interior. The ridge is forecast to press southeast of the area
with a warmer southerly flow developing late in the week which
could produce some upper 80s interior. 00Z GFS and ECMWF show
upper trough digging over the western US early in the week then
disagree on its evolution thereafter. The GFS shows a piece of the
upper trough moving east across the deep south inducing sfc low
development along the northern gulf coast Fri while the ECMWF
lifts the trough all in one piece into the Great Lakes, well north
of the area. Went with a model blend of 20-30 PoPs on Fri (Day 7)
but confidence is low.
Continued E/ESE flow will produce periods of BKN/OVC sky conditions
at FL040-FL060, with a few sprinkles and/or light rain showers
passing by the coastal terminals into the early afternoon.
Today/Tonight...High pressure remains north through the period,
providing continuous E/ESE flow. Expect the local pressure gradient
to relax during the day and winds to drop to around 15 knots by
early in the afternoon. Boating conditions will remain poor to
hazardous, with combined seas up to 7 feet lingering into the
afternoon. Small Craft Advisory for all but the nearshore Volusia
waters is set to expire this afternoon (5pm).
Overnight, winds around 15 knots will keep seas up to 6 feet
offshore. Small Craft should exercise caution into tonight.
Sun-Wed...Sfc low pressure north of Puerto Rico on Sunday is
forecast to deepen as it lifts north then northeast away from the
area. This feature will deform the high pressure ridge to the
north and a piece of the ridge will shift southwest toward the
area. This will result in a decreased wind flow but seas will
remain 4-6 feet as long period east swells become the primary
contribution to wave height. This should continue to produce
hazardous conditions near inlets for small craft especially during
the outgoing tide so will probably need a Caution headline but do
not foresee a Small Craft Advisory.
.PRELIMINARY POINT TEMPS/POPS...
DAB 79 63 79 61 / 10 10 10 10
MCO 82 61 83 61 / 10 10 10 10
MLB 80 65 79 61 / 10 10 10 10
VRB 79 65 79 62 / 10 10 10 10
LEE 82 61 83 62 / 10 10 20 10
SFB 81 61 82 61 / 10 10 10 10
ORL 81 62 82 62 / 10 10 10 10
FPR 79 64 79 60 / 10 10 10 10
AM...Small Craft Advisory until 5 PM EDT this afternoon for
Flagler Beach to Jupiter Inlet 20-60 nm-
Volusia-Brevard County Line to Jupiter Inlet 0-20 nm.