Area Forecast Discussion
Issued by NWS Melbourne, FL
FXUS62 KMLB 280842
Area Forecast Discussion
National Weather Service Melbourne FL
440 AM EDT SUN AUG 28 2016
...High Risk of Rip Currents in the surf zone today...
...Increasing threat for heavy rainfall through mid week...
Today/Tonight...All in all, not much has changed over the past 24
hours as the area remains sandwiched between a deep layer ridge well
to the north and weak low pressure across the Florida Straits.
Continued elevated easterly flow will tap a moist environment over
the Atlantic while the envelope of deepest moisture and highest
PWATs in association with the tropical wave remains to our south for
one more day.
With PWATs remaining at or above 2.0" and steady onshore flow
continuing, PoPs remain similar (30/40%) to the past several days.
Low end chances for showers will continue along the coastal counties
through late morning before convection develops and focuses over the
interior by the early afternoon. With continued mild temperatures
aloft, thunderstorm coverage is expected to remain limited; however,
residents and visitors are reminded that any storm is capable of
producing deadly cloud-to-ground lightning strikes. Warm east flow
will keep temperatures above normal tonight in the mid to upper 70s,
with low 80s along the immediate coast.
Increasing very long (16-17sec) period swell will produce a high
risk for rip currents in the central Florida Atlantic surf zone
today, which will warrant CFW statement issuance. Will also need
to headline/highlight as such in the HWO/ZFP.
Monday-Thursday...While precision is never a guarantee of accuracy,
the model consensus with respect to the tropical wave (omnipresent
"Invest 99L") has improved and trended toward a more coherent, and
stronger area of low pressure developing over the eastern GOMEX
during days 2-4. By sunrise Monday, the tropical wave axis will
extend from the lower keys to the NW Bahamas. Low pressure is
forecast to form well west of KEYW-KAPF an track NW offshore SWFL
out to about 88W through TUE night, before gradually turning north
on WED and NNE THU, moving onshore THU night somewhere between the
western panhandle and Big Bend region.
While uncertainty still exists as to the exact strength and track of
the low, what continues to be of greater confidence for ECFL is the
influx of very high (2.1" to 2.5") PWAT air northward across the
region Tuesday-Thursday. Regardless of whether or not convection
directly associated with the low remains off to the west through the
period, enhancement of the diurnal convective pattern seems quite
likely, and high POPs remain in order. Given slightly slower trend
of moisture advection, tweaked numbers down to 50/north to 70/south
for Monday, then up to 70-80 Tuesday, 60-70 Wednesday and 60 on
Thursday. We will need to see how the low evolves before refining
any potential flood threat for the area, or if there may be some
enhanced risk for wind gusts/squalls/tornado potential. Temps will
continue to be shaded a couple degrees below climo thru the period.
Friday-Sunday...Extended forecast will continue to favor the ECMWF
solution, which shows faster departure of the low through late Friday
/early Saturday, which should allow for gradual mean drying of the
air mass. However, residual SW flow remains in the low`s wake as the
Atlantic ridge rebuilds westward into south FL, which should favor
the central and eastern peninsula for at least climatological
chances of diurnal convection. Temps should rise back to and then
slightly above normal given the expected wind regime.
Maintaining VCSH over coastal terminals through at least late
morning as small chance exists for onshore moving showers. As is
typical with this type of pattern, timing of SHRAs and associated
VSBY/CIG reductions remains difficult, though impact to any one
terminal expected to be very short in duration. Focus for SHRA/TSRA,
remaining scattered in coverage, will shift inland by late this
morning and early this afternoon.
Today-tonight...Gentle to moderate easterly breezes will continue
today as weak low moves through the Florida Straits. Seas generally
3 - 4 feet nearshore and up to 5 feet offshore. Moisture will remain
sufficient to produce scattered showers and isolated thunderstorms
over the waters through the day. Wave models picking up on a long
period swell generated by distant Hurricane Gaston impacting the
east FL coast beginning this evening with dominant periods
increasing to 14 - 15 seconds.
Monday-Thursday...Southeast wind flow to start the week will veer
to south and then southwest by Wednesday-Thursday given northward
track of the anticipated low pressure area to our west. None of the
models tighten the gradient appreciably over the MAOR until after
the flow becomes offshore/SW. Consequently, the combination of wind
chop and long period swell keep seas AOB 5FT through the period.
Less then favorable boating conditions will be accompanied by an
increasing coverage of rain/storms and attendant threat for locally
higher winds and seas in gusty storms or squalls.
.PRELIMINARY POINT TEMPS/POPS...
DAB 91 77 89 77 / 30 30 50 40
MCO 92 75 91 77 / 40 20 50 30
MLB 90 79 89 77 / 40 30 60 40
VRB 89 77 87 77 / 40 30 60 50
LEE 94 75 92 77 / 40 20 50 30
SFB 92 75 91 77 / 40 20 50 30
ORL 92 76 91 77 / 40 20 50 30
FPR 89 77 88 77 / 40 30 60 50