Scientific Forecaster Discussion
fxus62 kmfl 110000 aaa
Area forecast discussion...updated
National Weather Service Miami Florida
700 PM EST Sat Dec 10 2016
the winds will be northeast tonight around 10 knots, except 15
knots at kfll taf site. The winds will be more easterly on Sunday
with speeds around 15 knots gusts to 25 knots. The ceilings should
remain in the MVFR conditions tonight before improving to VFR
conditions on Sunday at most of the taf sites. The only exception
to this is at kapf taf site where the ceilings will be in VFR
conditions. The visible should remain in VFR conditions tonight into
Sunday, but could fall down into MVFR conditions over the East
Coast taf sites with the passage of any showers.
Previous discussion... /issued 427 PM EST Sat Dec 10 2016/
This afternoon-tonight: the heavier rainfall from earlier has
diminished this afternoon, leaving mostly light to moderate rain
along the East Coast and Atlantic and sprinkles over the interior.
Weak low level boundary continues to oscillate across the region
providing focus for this activity. Overall, this will be the
pattern as we head into tonight under breezy east-northeast flow.
Models hint at a few ripples in the flow overnight that may help
enhance East Coast rainfall, especially as winds just above the
surface veer more east-southeast and increase coastal convergence
along the weak low level boundary in place over the region. Will
have to monitor for additional heavy rainfall convergent bands
setting up along the East Coast and potential for urban flooding,
especially if these occur where there has already been some heavy
Rain and clouds temper overnight lows which will drop into the
Sunday: breezy conditions continue into Sunday as winds veer more
easterly. Low level boundary continues its northward move during
the day, shifting the best rain chances towards Palm Beach County
and Lake Okeechobee with time. It will be another day of scattered
to numerous showers over the Atlantic and along the East Coast
with drizzle/light showers occasionally reaching into the interior
and the Gulf Coast. Locally heavy rainfall will remain a concern,
especially near the boundary.
Daytime highs will moderate back to normal with highs ranging
from the upper 70s to near 80. Overnight lows remain very muggy
around 10 degrees above normal in the mid 60s to low 70s.
Next week: South Florida will remain under the influence of weak
high pressure off to our north and east through mid week, with light
southeasterly flow. Low levels remain moist through the period, but
the near record level pwats that are in place this weekend will drop
as the mid levels dry out. This relatively drier air will remain in
place even as the next frontal boundary arrives around Thursday with
Isolated to widely scattered showers will continue across the
region, mainly for the East Coast Metro. Temperatures will be near
to slightly above normal for mid-December.
Marine...tight pressure gradient between high pressure over the
southeast and quasi-stationary boundary across the Florida Straits will
continue to bring gusty east-northeast winds and hazardous marine
conditions through the remainder of the weekend.
Wind speeds will generally be in the 20-25 knot range over
the local Gulf and Atlantic waters, including Biscayne Bay, with the
potential for occasional gale force gusts over the Atlantic. Rough
seas can also be expected through the weekend with seas of 7-10 feet
over the Atlantic and 5-7 feet in the offshore Gulf waters.
Surface high weakens and moves into the Atlantic early next week
allowing winds to ease as they veer southeast. Marine conditions
improve by late Monday with decreasing winds and seas.
Beach forecast...gusty northeast winds will lead to a high risk of
rip currents for the Atlantic beaches through Sunday, with the risk
likely remaining elevated into Monday. The risk will begin to
decrease beginning late Monday and into Tuesday as the flow shifts
to the southeast and weakens.
Aviation...Atlantic showers will continue to spread across the
East Coast terminals, particularly mia, opf, and tmb, this
afternoon and evening. MVFR cigs are expected, with bouts of IFR
cigs and vsbys with heavy rain showers. Some sites could improve
to VFR briefly, mainly pbi. Apf should remain MVFR or better.
Gusty northeasterly to easterly flow is expected through much of
the period. MVFR cigs could linger into Sunday.
Preliminary point temps/pops...
West Palm Beach 70 79 69 84 / 40 40 30 20
Fort Lauderdale 70 78 71 83 / 60 50 30 30
Miami 69 79 71 83 / 50 50 30 20
Naples 64 80 67 83 / 10 10 10 20
Florida...high rip current risk through Sunday evening for flz168-172-173.
Am...Small Craft Advisory until 10 PM EST Sunday for amz630-650-651-
GM...Small Craft Advisory until 4 am EST Sunday for gmz656-657-676.