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Area forecast discussion 
National Weather Service Melbourne Florida
321 PM EST sun Dec 28 2014

Discussion...

..chance of dense fog again late tonight...

Tonight...
ridge axis extending from Bermuda to the Bay of Campeche low level SW
flow will interact with a frontal trough over the deep south to
maintain a deep S/SW flow across central Florida. The srly flow coupled
with surface dewpoints in the 60s areawide will keep min temperatures around 15f
above climatology average...l/m60s interior and M/u60s along the coast.

Primary weather concern will be the formation of stratus/fog due to
fairly high moisture trapped below a sharp subsidence inversion in the
h90-h75 layer...RUC analysis showing upstream h100-850 mb mean relative humidity values
between 70-80pct. With little to no middle/upper level cloud cover overhead...
where/when fog will form will depend on the strength of the
boundary/low level flow. At this time...it appears the pgrad will be a little
tighter than Sat night as the frontal trough presses across the
Panhandle/eastern Gomex and into the western flank of the ridge. This should
limit the extent/duration of dense fog to areas along and north of the
I-4 corridor during the predawn hours. Patchy/areas of general fog
elsewhere.

Monday...
little change in the current weather pattern as the primary h30-h20 jet
streak driving the front has a lifting orientation that is more or
less parallel to the southern extent of the boundary. Without a digging trough
to uproot the ridge...the front will be left with little more than
its forward momentum to advance eastward...a progress that will be slow
at best given the position of the ridge axis. Low energy airmass
beneath the ridge with no sig vorticity or Omega lift...h50 temperatures
around -8c...and a 5-8c subsidence inversion through the h95-h70 layer that
will effectively cap vertical motion well below 10kft. Precipitation will
remain too low to mention.

Fog/stratus will linger past dawn but should burn off by middle morning.
Partly/mostly sunny skies and a continuing S/SW flow will produce afternoon maximum
temperatures in the l/m80s...5-10f above average. By and large...Monday maximum temperature
records look safe...though Orlando could tie depending on how
quickly any stratus/fog Burns off.

Monday night-Wed...
not much change in the forecast to close out 2014. Rather broad
northern stream trough evolves through the period. This will cause
flow aloft to veer to westerly with 500 mb heights falling
slightly. Associated weak surface front will have considerable
trouble getting past the Stout Ridge in place over the state...and
instead limp anemically into the region Tuesday and Wednesday...eventually
becoming aligned west/east vicinity northern Bahamas late Wednesday.

We will continue to see abundant low level moisture with rather
unable-December like dewpoints in the middle-upper 60s ahead of the front
Tuesday. Middle level moisture looks minimal...and without any upper
level support the best rain chances will come with the minimal
lift provided by the front. Will keep best rain chances (20-30%)
Monday night-Tuesday night with the front.

Temperatures will continue above normal with highs in the upper
70s to lowers 80s Tuesday. Then as winds veer quickly to the northeast
Wednesday behind the front...there will be a little cooling but readings
will stay near to above normal.

Thursday-next sun...
frontal boundary or its remnants move into South Florida by Thursday
as the large cold surface high spilling across the eastern 2/3rds
of the country bridges it...leading to breezy north-northeast
flow.

While northern areas may dry out a little more...higher low level
moisture never really scours out of Okeechobee and the Treasure
Coast...especially as flow becomes more easterly on Friday.
Consensus MOS still shows slight chance probability of precipitation along the coast new
years evening and will retain this for continuity sake...but do not
expect a lot of coverage or much in the way of significant rainfall.

Otherwise...consensus MOS keeps low end probability of precipitation in through much of the
period...and for now will keep the mention confined to the waters
as land impacts look to remain minimal beyond persistent cloudiness
and the occasional sprinkle.

Upper level and surface ridging will build back across the region
late Friday into Sat pushing old frontal trough back to the north.
Southern upper level low left behind over The Four Corners region
will kick out to the east and open up into a trough Friday and Sat...
driving a potent storm system across the deep south and into the
middle part of the country.

Latest model runs show that the storm system will lift out too
quickly to cause much of a front to reach the area by next
weekend...with the GFS holding it off completely and the European model (ecmwf)
showing a weak boundary limping into the area next Sunday.

&&

Aviation...through 29/18z
surface wnds: through 29/03z...S/SW between 5-8kts...becoming S/southeast coastal sites after
28/18z. After 29/03z...S/SW at or below 3kts.

Visibilities/wx: through 29/03z...VFR all sites. After 29/03z...prevailing MVFR
br all sites...north of ktix-kism areas LIFR in fog.

Cigs: through 29/03z...VFR all sites. After 29/03z...prevailing MVFR between
fl010-020 all sites...areas LIFR below fl004 north of ktix-kism.

&&

Marine...
tonight-Monday...hi pressure ridge axis extending from Bermuda across S Florida
to the North Shore of the Yucatan Peninsula will combine with a slow
moving cold front over the deep south to maintain a S/SW breeze across
the local Atlantic to start the week...light to gentle S of Cape
Canaveral...gentle to moderate north of the cape due to slightly tighter
pgrad. Seas 3-4ft nearshore and 4-5ft offshore overnight... almost
all of which will be due to a long period Erly swell. Seas becoming 2-3ft
nearshore and 3-4ft offshore after daybreak as the swell begins to
dampen out. The long period swell will generate a high rip current
threat at area beaches Monday afternoon.

Tue-Fri...a frontal boundary is forecast to slide through the
waters Tuesday and bring a chance of showers. A north/northeast surge
possibly to 15 knots is indicated Tuesday night into Wednesday. The front
will stall out just to our south late in the week with winds
gradually veering around to east by Friday. Right now speeds look to
be 10-15 knots late in the week. Considerable low level moisture
lingering after the frontal passage...and a long northeast wind
fetch...should start to cause isolated Atlantic showers.

&&

Climate...
record highs today... forecast
record high
Daytona Beach 83/1988 81
Orlando 85/1916 83
Melbourne 87/1981 82
Vero Beach 84/1981 82

Record highs Monday... forecast
Daytona Beach 83/1946 80
Orlando 84/2007 83
Melbourne 84/1973 82
Vero Beach 85/2012 82

&&

Preliminary point temps/pops...
dab 62 80 65 77 / 0 10 20 30
mco 62 82 64 80 / 0 10 20 30
mlb 66 81 68 79 / 0 10 20 30
vrb 66 81 66 80 / 0 10 10 30
Lee 62 81 64 78 / 0 10 20 30
sfb 63 81 65 79 / 0 10 20 30
orl 63 81 65 78 / 0 10 20 30
fpr 65 81 65 80 / 0 10 10 30

&&

Mlb watches/warnings/advisories...
Florida...none.
Am...none.
&&

$$

Short term...bragaw
long term....lascody

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