Scientific Forecaster Discussion
fxus62 kmfl 251818
Area forecast discussion
National Weather Service Miami Florida
118 PM EST Sat Feb 25 2017
the weather is forecast to be mostly dry across South Florida.
However, there is a weak trough slowly moving across the area
tonight, which may bring some isolated showers, and a wind shift
towards daybreak tomorrow. For the taf period, VFR conditions are
forecast. There is a potential for fog development once again for
the interior areas. Models are currently keeping the fog away from
the coast lines. However, this may need to be added later this
evening if the models increase the coverage of fog tonight. For
tomorrow morning, the wind will shift to the northwest, and then
even northeast by mid morning, behind the trough.
Previous discussion... /issued 1002 am EST Sat Feb 25 2017/
the main changes to this mornings update was to adjust to current
conditions, and add patchy fog for the interior areas for
tonight, as the sref does indicate it is possible once again.
However, the sref is not indicating an impact to the East Coast
Metro areas like today. Also, reduced the rip current risk down
to low today for Palm Beach County beaches, as there were no
reported rip currents yesterday, and conditions are improving
Previous discussion... /issued 431 am EST Sat Feb 25 2017/
Discussion...latest surface analysis shows weak trough over the
Miami/Fort Lauderdale area and extending east into the Bahamas
leading to some cloudiness over these areas that stretches back
toward the adjacent waters of the SW Florida coast also. Light
winds, clearing skies aloft and sufficient surface/low level
moisture favored the formation of fog and low clouds early this
morning particularly in the presence of this boundary across the
interior and SW Florida coast. Light warm and moist southeast flow noted
in the 00z sounding across the area over a relatively cooler sfc
layer is also another indicator of favorable conditions and it is
under this setup we also tend to see low level stratus and/or fog
across the adjacent Gulf waters as well where waters are cooler
than in the Gulf Stream waters of the Atlantic. This is
corroborated by the split window channel loops from GOES. It is in
the vicinity of this boundary that the denser fog has developed
this morning leading to an advisory for Miami Dade and portions of
Broward and inland Collier. Elsewhere, it has been mostly a mix
of low clouds and patchy fog but dense fog cannot be totally ruled
out. A statement is also in effect for areas outside the
advisory. Advisory in effect through 9 am this morning. Conditions
should improve gradually after sunrise.
Short term...through Monday. There is still a remote possibility
of fog once again on Sunday morning. However, aforementioned
surface trough should be well east of the area and forecast winds
from a variety of models indicate winds above sfc layer not
favorable so opted to leave it out of the forecast for now.
However, this will need to be revisited later today as some of the
model output statistics show hints of the possibility
particularly for the West Coast and interior.
Model consensus still shows weak front approaching area on Sunday
and dissipating as we move into Monday over the area. Rain chances
with this front will remain slight at best. However, daytime
temps will cool down a bit to near normal tomorrow before quickly
beginning to warm up again on Monday.
Extended term...through end of the week.
Behind the front, a large region of high pressure will build
to our north and move quickly offshore by early in the week. This
will result in increasing easterly flow from late Sunday through
early in the week before winds slacken as the ridge moves well
into the Atlantic and pressure gradient weakens across the area
towards the middle of the week. Low to mid level high during the
week will have associated heights that will be well above normal
per ensemble systems and this indicate temperatures will be
running well above normal through the week. Rain chances will
remain limited through much of the week and increase a bit as a
weak frontal system approaches the region on Thursday.
Marine...a lingering swell of 1 to 3 feet offshore Palm Beach
will continue to retreat through tonight. However, seas will
increase across the Atlantic waters on Sunday and into Monday
behind the aforementioned front as winds increase from the north
and then east through the period. Seas will reach 4 to 6 feet
across much of the Gulf Stream waters and 5 to 7 feet off Palm
Beach County with occasionally higher seas before beginning the
subside on Monday.
Preliminary point temps/pops...
West Palm Beach 83 66 79 73 / 0 10 20 20
Fort Lauderdale 83 66 80 72 / 10 10 20 20
Miami 85 67 81 71 / 10 10 20 20
Naples 79 62 81 64 / 0 0 10 10