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Area forecast discussion 
National Weather Service Miami Florida
1259 PM EST Sat Dec 27 2014


Residual low level moisture, underneath the inversion this am, has
allowed cumulus around 3kft to form, along the East Coast. The cloud
layer was most prodigious across Palm Beach County, where more
low level moisture resides near the diffuse boundary. Thus, can't rule
out a few hours of MVFR ceilings at kpbi, and evev kfll/kfxe today.
Lower ceilings appear to be moving away from other terminals with
easterly surface flow. Nice slice of drier air above inversion
should continue mixing down into late afternoon.

Sref again showing decent probs of IFR visible and some ceiling overnight,
but looks to be away from the airports with the exception of apf.
Sref probs also noteworthy at pbi although guidance not
responding. Conds are not nearly as favorable as last night,
without the numerous coastal showers of Friday along the East
Coast. However, fair confidence at apf with lamp showing
restrictions. Canadian simulated cloud cover depicting clouds
coming ashore along the East Coast with an increase in moisture at
850 mb late tonight. Ceilings could be near 3kft if this occurs.
Improvement at apf Sunday morning could be slow again. Perhaps
more broken ceilings along the East Coast Sunday afternoon.


Previous discussion... /issued 940 am EST Sat Dec 27 2014/

made some earlier adjustments to cancel dense fog advisory
although fog has been slow to completely erode due to extensive
high level clouds streaming across South Florida in active
subtropical jet. Frontal boundary continues to lift slowly north
over the region and becoming diffuse as it does so as upper ridge
builds in from the Caribbean. This should allow for a clearing
sky by early this afternoon as a drier airmass moves in from the
south. The 12z mfl sounding already indicates significant low
level drying from 24 hours ago. No other changes are planned at
this time with marine zones in good shape.


Previous discussion... /issued 712 am EST Sat Dec 27 2014/


Visible has already improved to VFR at some terminals, with apf slower
to improve this morning with IFR possibly remaining for a few
more hours. All terminals should improve to VFR by late morning as
drier air arrives from south to north with a weak boundary washing
out. With low level moisture in place this morning, there could be a
few MVFR ceilings early before clouds rise and clear.

Previous discussion... /issued 145 am EST Sat Dec 27 2014/

Dry weather over South Florida this weekend before a slight
chance of showers early to middle of next week...

Short term...
patchy to areas of dense fog has developed over most of South
Florida early this morning which should continue through the early
daylight hours. The only exception to this is for the east
coastal areas of South Florida where the fog should be more
isolated in coverage and remain above 1/4 of a mile in visible.
Therefore...a dense fog advisory will continue until 8 am EST this
morning for most of South Florida...except for the east coastal
areas of South Florida.

A frontal boundary over Lake Okeechobee region early this morning
will continue to dissipate allowing for high pressure over the
western Atlantic waters to build across the central Florida
Peninsula this weekend. This will allow for an east to southeast
wind flow over South Florida bringing in drier air from the
Atlantic waters. Therefore...the weather will be dry this weekend
over South Florida with temperatures well above normal for this
time of year. Highs will be in the 80s with lows in the 60s except
around 70 East Coast metropolitan areas.

Long term...
the high will then shift back east into the western Atlantic
waters early next a trough of low pressure over The Four
Corners moves northeast into the southern Gulf Coast states. This
in turn will allow for low pressure to develop over Texas and
move northeast into the southeastern United States pushing a cold
front southward into central Florida. This will allow for the wind
flow to become more southerly over South Florida and allow for a
few showers over northern areas by Tuesday.

The low will continue to move northeast into the Middle Atlantic
States by middle of next the front moves into South
Florida and dissipates. So the slight chance of showers will
continue over South Florida for middle of next week with the best
chance over the East Coast metropolitan areas. High pressure will then
build back into South Florida for late next week bringing back the
dry weather to the area.

the winds will be easterly this weekend before swinging more
southerly early next week ahead of a weak cold front. Wind speeds
will be mainly 10 knots or less this weekend into early next week
over all of South Florida waters. This will keep the seas at 2
feet or less in both the Atlantic and Gulf waters of South Florida
this weekend into early next week.


Preliminary point temps/pops...
West Palm Beach 67 82 70 82 / 10 10 10 10
Fort Lauderdale 69 82 72 82 / 10 10 10 10
Miami 69 83 71 83 / 0 10 10 10
Naples 65 82 66 82 / 0 10 10 10


Mfl watches/warnings/advisories...


Short term...30/kob
long term....30/kob

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