Area Forecast Discussion
Issued by NWS Melbourne, FL
FXUS62 KMLB 161451
Area Forecast Discussion
National Weather Service Melbourne FL
950 AM EST Mon Jan 16 2017
...High Risk of Rip Currents at the beaches today...
...Above Normal Temperatures will continue this week...
Current...Western Atlantic high pressure center offshore north
Florida is in the process of getting reinforced/absorbed by a
stronger high to the north. Steady ESE surface-2KM flow is in place
across the central and southern peninsula this morning. A mix of
marine CU (at 3.0 - 3.5KFT), SC "pancaking" against the strong
subsidence cap just about H85 (5-6KFT) and CS is producing a few
areas of significant cloud cover, otherwise partly to mostly sunny
conditions prevail, with 9AM temps in U60s-L70s.
Remainder of today...expect another warm and precip-free day as the
mean local air mass remains relatively dry/capped by ridging aloft.
Lingering long period swells will keep the Rip Current danger high
once again through sunset. Forecast looks on track with the usual
cosmetic tweaks to temps/winds/skies and removal of the mention of
early morning fog.
.AVIATION...VFR. AREAS of CIGs near BKN-OVC060 look like a good bet
again this afternoon given the strong cap in place and the narrow
moist layer beneath it. Some late fog possible again late tonight,
however it seems like MOS may be overdoing its extent, given the
flow regime in place. We shall see...
MARINE...ESE winds around 10-12KT north of the Cape and and 12-15KT
knots to the south with seas 3-4FT near shore and 4-5FT offshore.
LONG TERM/IMPACT WX...Lascody
.PREV DISCUSSION... /issued 255 AM EST Mon Jan 16 2017
Tonight...Low level winds will veer to the SE at H9 overnight
thought sfc winds will go calm to light. Should see some radiational
late night fog mainly across the nrn interior. Will continue patchy
wording...though could be more prevalent from I-4 northwestward
late. Lows will drop into the 50s inland and lower 60s along the
Tuesday-Wednesday...Deep layer ridging encompasses the Florida
peninsula but does begin to weaken/flatten out later in the period
as pieces of the elongated upper troughing, extending from the Great
Lakes through the Desert Southwest, push off of the northeast
U.S./Mid Atlc States. Surface ridging north of the area early in the
period will settle southward to across the central FL peninsula Tue
night/Wed. This, as a frontal boundary drops southward from the Mid
Atlc states Wed night across the southeast U.S./north FL. Winds
respond briefly Wed overnight by becoming light northerly.
PWAT values remain forecast under one inch through early Wed and
with the fairly strong subsidence across the area will keep
precipitation chances absent from the forecast. The overall pressure
gradient remains weak and winds generally light during the day and
near calm at night. The greatest weather concern will revolve around
fog development each night/morning. Highs will continue above climo
in the U70s/L80s. Lows will continue above normal as well generally
in the M-U50s with a few spots in the L60s.
Thursday-Sunday...Shortwave ridging aloft will move across the
Florida peninsula on Thu. The flow aloft remains nearly zonal, with
any decent shortwave activity keeping north and west of the area,
until Sun night when an expansive upper low over the central CONUS
digs further southward. At the surface, winds quickly become light
onshore again on Thu as the previously mentioned backdoor front
moves away from the Florida east coast. An area of low pressure over
the ArkLaTex region with associated upper energy lifts northeastward
into the Tennessee Valley on Thu and Ohio Valley Thu night keeping
the Deep South in the warm/moist sector into the weekend.
Deep layer moisture values will steadily increase into the weekend
with PWAT values in upwards of 1.40-1.60 inches at times thru Sun
afternoon. A more significant surface cold front will traverse the
GOMEX on Sun, then is forecast by medium range models to push across
ECFL Sun overnight/early Mon morning. The ECMWF remains a bit faster
with this system compared with the GFS.
For PoPs, continue to keep Thu dry for now and will introduce a
small threat Fri afternoon/evening across the I-4 corridor for
possible shower activity. On Sat, enough moisture, heating, combined
with some weak energy aloft may allow for some convection KMLB
northward, mainly in the afternoon. Will keep thunder mention out of
the forecast on Sat. At present, believe we are safe from most
convection Sun morning ahead of the next approaching front, but
chances increase steadily later in the afternoon (north) as moisture
deepens further and added surface heating. Have added a SCHC threat
for thunder I-4 corridor northward on Sun. Increasing shower/storm
chances areawide Sun night and this will be our greatest
precipitation threat areawide over the extended. Currently have 40-
50 percent chances and this may continue to increase with further
confidence leading up to the event. There will be the potential for
a few strong storms Sun night, but this is too far out to narrow out
any exact threats just yet.
Temperatures may realize a few degrees cooler on Thu with passage of
the aforementioned backdoor front, but will quickly rebound back
into the U70/L80s for highs Fri-Sun. Overnight lows remain milder
than average and generally in the U50s/L60s.
Broken cirrus moving across the area during the early morning hours
should keep BR/FG patchy across nrn terminals thru 13z. May see some
periods of brief MVFR/IFR KISM to KDAB corridor including KLEE.
Otherwise VFR today with BR/FG prospects looking good for nrn
terminals aft 17/06z.
Tuesday-Friday...The surface ridge axis begins north of the coastal
waters on Tue but will drift southward to across the central FL
peninsula Tue night/Wed, then drift further south and east away from
the area into late week. A brief back-door front will slide
southward across the waters Wed overnight/early Thu. The pressure
gradient remains generally weak with surface winds AOB 15 kts.
Initial seas of 3-4 ft will subside to AOB 3 ft during the period.
.PRELIMINARY POINT TEMPS/POPS...
DAB 79 58 78 57 / 10 0 10 0
MCO 80 58 81 59 / 0 0 10 0
MLB 79 61 78 59 / 0 0 10 0
VRB 78 61 79 58 / 10 0 10 0
LEE 80 58 80 60 / 0 0 10 0
SFB 80 59 80 59 / 0 0 10 0
ORL 80 60 80 61 / 0 0 10 0
FPR 77 59 79 57 / 10 0 10 0