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Area forecast discussion 
National Weather Service Miami Florida
326 PM EST Friday Dec 19 2014

Discussion...
generally light easterly winds are expected to veer to the
southeast and increase slightly through the weekend. This will
translate to a slight warming trend with mainly rain free
conditions with weak high pressure across the western Atlantic and
mainly zonal flow aloft.

Boundary layer moisture will increase through the weekend as an
area of low pressure across the western Gulf of Mexico moves to
the northeast aided by a weak upper level impulse. This system
will quickly exit into the western Atlantic by Monday bringing
rain chances mainly for the central and Northern Peninsula with
lesser chances further south. A thunderstorm or two could be
possible late Sunday into Monday mainly across the Lake Okeechobee
region but not very confident due to the lack of any real
forcing. However...did mention a slight chance for thunder Monday
afternoon as diurnal heating could spark an isolated thunderstorm
especially along the Atlantic coast with weak sea breeze
convergence. A few showers may linger into early Tuesday.

Deep moisture rich southwest flow will then become firmly
entrenched across the Florida Peninsula on Tuesday as a highly
amplified 500 mb low begins to dig southward across the middle
Mississippi Valley. This low is then expected to take on a more
negative tilt allowing the associated surface low to deepen across
the Great Lakes. This will reinforce warm air advection across the Florida
Peninsula on Tuesday allowing temperatures to surge into the low
to middle 80s across most of South Florida Tuesday afternoon. As the
500 mb low digs further south...a line of showers and thunderstorms
are expected to form along the surface cold front late Tuesday
into early Wednesday across the eastern Gulf of Mexico and push
into South Florida on Wednesday. Best dynamics should remain well
north of the area along with the more favorable jet structure.
However the surface forcing along with ambient heating should be
more than enough to facilitate a decent coverage of thunderstorms
Wednesday as the front passes through. Both the GFS and the European model (ecmwf)
remain in good agreement with the timing and intensity of this
system.

Showers and thunderstorms should exit the area by late Wednesday
with a much cooler and drier air mass expected to filter into the
area by Christmas morning. Consensus models currently show high
temperatures Christmas day struggling to reach 70 degrees as cool
high pressure takes control. Dry and slightly warmer weather
should then prevail Friday into the weekend.

&&

Aviation...
high pressure will keep rain free conditions across South Florida
through the taf period with generally light east to southeast
surface flow. Patchy fog is possible tonight with minimum impact
to the taf sites.

&&

Marine...
good boating conditions will continue through the weekend with
high pressure in control. A cold front will approach South Florida
on Tuesday and move through the local waters on Wednesday. This
will result in the wind veering to the southwest and then
northwest behind the front with building seas through Christmas
day.

&&

Preliminary point temps/pops...
West Palm Beach 63 77 65 78 / 0 10 10 10
Fort Lauderdale 66 77 67 78 / 0 0 10 10
Miami 65 78 66 79 / 0 0 10 10
Naples 58 77 61 78 / 0 0 10 10

&&

Mfl watches/warnings/advisories...
Florida...none.
Am...none.
GM...none.
&&

$$

Short term...10/cd
long term....10/cd
aviation...71/je

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