Scientific Forecaster Discussion
fxus62 kmlb 130745
Area forecast discussion
National Weather Service Melbourne Florida
245 am EST Wed Dec 13 2017
Today...a dry front will sweep southeast from South Florida early this
morning and through the Bahamas this afternoon. In its wake deep
layer drying and northwest flow will keep skies sunny with cool
afternoon high temperatures in the lower 60s nrn sections to the mid
60s central and south.
Tonight...surface high pressure will drift east toward South Florida
overnight as another frontal boundary moves toward the southeast.
Proximity to the surface high across southern sections should allow
lows to drop into the upper 30s inland from the coast and across
Okeechobee County. Across nrn sections...westerly low level flow off
the Gulf to 20-25 knots at 925 mbs will moderate temps some with
lows mainly in the lower 40s and in the mid 40s in urban areas and
near the larger Inland Lakes.
Thu-sun...models show a more zonal flow aloft into Thursday, with a
short wave trough axis moving through the Midwest and into the southeast
Friday. This will initiate a slow southward progressing weak cool
front across the region late Friday and into the weekend. High
pressure behind this boundary will shift northeast toward the mid-
Atlantic coast and offshore into the Atlantic on Sunday.
Low level moisture increases out ahead of this boundary into late
week in the westerly flow. However any mentionable rain chances look
to hold off until Friday when sufficient low level moisture and
enhanced support for lift from jet north of the area may be able to
generate a few showers through the afternoon. Still, rain chances
remain low with pops ranging from 20-30 percent over mainly central
and northern portions of the region. Dry conditions then expected
through the weekend as front shifts south and stalls near Lake
Okeechobee region early Sunday.
Temperatures will warm to more seasonable values into late week,
with highs reaching the low to mid 70s, and lows in the 50s. A
slight and brief cool down then expected mainly for northern
portions of central Florida Saturday behind the front, with highs in
the mid to upper 60s. As onshore flow strengthens with high pressure
building off the eastern Seaboard, temperatures again warm into the
mid to upper 70s for highs on Sunday.
Mon-Wed...models begin to diverge in their solutions into early next
week regarding the passage of the next cool front to move through
the area. The European model (ecmwf) shows a stronger and faster progressing trough
through the central and eastern U.S. That weakens ridge across the
Caribbean region and pushes front and showers associated with this
boundary through Florida during the Monday/Monday night timeframe.
However, the GFS delays this frontal passage until late week,
keeping greater moisture and rain chances north of the area Mon-Tue.
Due to these model differences and lower confidence in the forecast
this far out will only mention a slight chance for showers in the
forecast for Monday. Highs will remain above normal Monday in the
upper 70s to low 80s and then some slight cooling back to more
normal values expected once frontal boundary is able to move through
skies will be mainly clear with VFR and dry flying weather today.
Short range guidance indicates some marine stratocu from the Gulf
may make it to klee vcnty after 06z.
today...northwest winds to 15-20 knots near shore and 20 knots offshore
early this morning will decrease to 10-13 knots offshore into the
afternoon hours. Will continue advisory for the offshore waters into
late morning and headlines scec near shore.
Tonight...westerly winds to around 15 knots nrn waters and 10 knots
south will allow seas to gradually subside to 2-3 ft near shore and
around 4 ft offshore.
Thu-sun...an offshore flow with wind speeds up to 10-15 knots, and
seas ranging from 1-3 feet will generally persist into late week. A
weak cold front is then forecast to move through the region Friday
night into Saturday, switching winds briefly out of the north and
building seas to 4-5 feet offshore. High pressure building offshore
north of the area will then allow winds to quickly veer onshore into
Sunday, with speeds forecast to remain less than 15 knots and seas
around 2-3 feet.
today...min rhs will drop to 25-30 percent across the interior this
afternoon with northwest winds lowering to 5-10 mph through the afternoon.
Decreasing winds through the day and low erc values are expected so
no headlines will be needed. Thu/Fri...southwest flow from the Gulf
will moisten low levels some with min rhs around 50 percent.
Preliminary point temps/pops...
dab 61 43 71 56 / 0 0 10 10
mco 63 45 72 55 / 0 0 0 10
mlb 65 40 71 56 / 0 0 0 10
vrb 65 38 71 53 / 0 0 0 10
Lee 63 46 71 57 / 0 0 10 10
sfb 63 45 72 56 / 0 0 10 10
orl 63 46 71 57 / 0 0 10 10
fpr 65 37 71 52 / 0 0 0 10
Am...Small Craft Advisory until 4 am EST early this morning for
Flagler Beach to Volusia-Brevard County line 0-20 nm-
Sebastian Inlet to Jupiter Inlet 0-20 nm-Volusia-Brevard
County line to Sebastian Inlet 0-20 nm.
Small Craft Advisory until 10 am EST this morning 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.