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Area forecast discussion 
National Weather Service Key West Florida
536 am EDT Thursday Aug 25 2016

another active night for the waters near the Florida Keys, as showers
and thunderstorms have been developing south of the Lower Keys and
north of the Middle Keys. A high pressure in the mid levels over
southeast United States and stretching at the surface from the
southeast to the northwest Atlantic this morning has kept winds from
the northeast locally, bringing with it moisture and an upper level
trough instability. Thanks to the rainfall at the Key West Airport,
which so far has been near a quarter of an inch since 1 am, the
temperature at the Airport dropped to 75 degrees while Marathon
Airport remained in the mid 80s. Winds have been from the northeast
to east generally 10 to 15 knots.

today through Saturday night...the high pressure will remain in place
over southeast United States through at least Monday. This will keep
winds from the northeast to east locally. Precipitable water values will continue
to be near 2 inches and with enough instability in the area, the
chances for showers and thunderstorms will remain. This afternoon,
and possibly fridays and saturdays too, with winds from the east to
northeast in the lower levels, expect the development of clouds over
the Keys, mainly over the Lower Keys, and consequently, the occurence
of showers and thunderstorms. Temperatures will have the potential to
reach the near 90s and cool down to the mid 80s with any rainfall

Sunday through Wednesday...currently, a tropical disturbance just
off the northeast coast of Dominican Republic continues without a
closed circulation even though it has near gale-force winds. The
latest model guidance from the GFS and European model (ecmwf) continue to show
different solutions for this system from Sunday on at the local area.
GFS brings a tropical wave for the Keys Sunday night while the
European takes a strong tropical storm over South Florida. Since the
system still lacks organization, these forecasts are uncertain at
this time. As the system moves west northwest north of the Greater
Antilles during the next few days, environmental conditions are
expected to become more conducive for development. For now, Florida
Keys residents and visitors should continue to monitor the progress
of this system. We are moving towards the peak of the hurricane
season, therefore it could be a good time to review your preparedness
plan. The local forecast, mainly for winds and wave heights, was kept
conservative due to the uncertainty of the situation. Regardless of
development, wet conditions are expected from Sunday through the end
of the forecast period.


northeast to east winds of 10 to 15 knots have been reported by the
marine stations in the Florida Keys. Gusts near 25 knots were
observed near thunderstorms in the Lower Keys earlier this morning.
Winds are expected to come down a notch today to near 10 knots
through Saturday night. As mentioned above, forecast from Sunday on
remains uncertain at this time. However, it will be updated as new
guidance becomes available and models get a better handle of the
tropical disturbance.


while VFR conditions will prevail, conditions are favorable for the
development of island cloud lines in addition to the widely scattered
showers and a few thunderstorms across the broader area. Brief
periods of gusty winds and sub VFR conditions will be possible,
especially at the eyw terminal. Away from convection, surface winds
will be out of the east at around 10 knots.


Preliminary point temps/pops...
Key West 89 79 90 80 / 40 40 40 40
Marathon 92 79 92 80 / 40 40 40 40


Key watches/warnings/advisories...



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