Area Forecast Discussion
Issued by NWS Miami, FL

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FXUS62 KMFL 241727

Area Forecast Discussion
National Weather Service Miami FL
127 PM EDT TUE MAY 24 2016

Showers and storms have developed almost on cue this afternoon,
along the Atlantic sea breeze. The HRRR is showing KAPF may not
see any convection this afternoon, so have reduced weather mention
to VCSH for now. For the remainder of the afternoon into the
evening, the activity should taper off between 00z and 02z,
looking from north to south, so have SHRA VCTS in for all sites
until 01z or 02z, with the earlier time being to the north.
Otherwise, VFR conditions through the TAF period, with brief IFR
under heavy showers and storms.


.PREV DISCUSSION... /issued 828 AM EDT TUE MAY 24 2016/

Some minor tweaks to the forecast this morning, mainly for sky
cover, as most sites are reporting mostly clear skies, as well as
looking pretty clear on the IR imagery. Also, tweaked PoPs to
include the latest hi-res model runs.

VFR conditions through the day, with the exception of some brief
IFR possible under any heavier showers or thunderstorms that may
develop. Have kept VCTS, or added as needed for this afternoon,
although there is still a little uncertainty in the timing of
the development.

PREV DISCUSSION... /issued 439 AM EDT TUE MAY 24 2016/

The front that pushed into South Florida the last couple of days
has stalled out and will be draped over the area today as a
quasi-stationary boundary. A ridge of high pressure will build
over the southeast states in the wake of the departing northeast
U.S. system, leaving a pocket of cool air and lower heights aloft
stranded over South Florida and the Bahamas. With the ridge
building to the north, a predominant easterly flow will be in
place, allowing the Atlantic sea breeze to move well into the
interior this afternoon.

With relatively cool air aloft (-10C at 500 mb) and the
aforementioned boundaries, numerous showers and thunderstorms will
develop with today`s diurnal heating. Most of the convection-
allowing models (CAMs) are quite aggressive developing showers and
thunderstorms early this afternoon over the southeast Florida
metro corridor, and then focusing into the interior and southwest
Florida by late afternoon. In fact, CAMs are nearly unanimous
depicting an area of at least one inch of rain accumulation in the
southwest interior this afternoon. So the POP and QPF forecasts
are aggressive in that area.

The surface boundary should settle over the southern tip of the
Peninsula or northern keys Wednesday, leaving a slightly drier
low level air mass over much of South Florida with surface
dewpoints and layer precipitable water values much lower than
previous days. Therefore rain chances will not be as high
Wednesday afternoon, but with lingering cold air aloft, afternoon
surface heating, and moist easterly low level flow off the
Atlantic, some afternoon showers will still be expected,
particularly near the remnant boundary over the southern part of
the peninsula.

With moderate to gusty easterly winds in place, at least a
moderate risk of rip currents is expected at the Atlantic Beaches
the next two days.

The slightly drier air mass will remain in place Thursday with
only low rain chances over the southern third of the area. The
pocket of lower heights and colder air aloft over the Bahamas
is likely to begin to develop a surface reflection by Thursday,
either in the form of an inverted trough or weak surface low. As
the southeast U.S. ridge begins to weaken and move east by the
weekend, this system will begin to feel the influence of a
negatively tilted upper trough ejecting out of the Plains,
inducing a general movement toward the northwest. This will keep
South Florida generally on the drier side of the system. However,
the surface ridge breaking down should allow the old boundary to
wash out, allowing the return of deeper moisture to the area. With
relatively weak gradients over the area, diurnal sea breeze
convection will be the main weather of interest.

Moderate to fresh easterly breezes will dominate through Wednesday
night, with sustained winds 15 to 20 knots bringing 4 to 5 foot
seas off shore. Small craft should exercise caution. As the ridge
breaks down by late week winds and seas will settle somewhat.


West Palm Beach  73  85  73  84 /  20  20  10  20
Fort Lauderdale  75  85  75  84 /  40  30  20  30
Miami            74  85  75  84 /  50  40  30  30
Naples           71  90  69  89 /  20  30  20  10


.MFL Watches/Warnings/Advisories...


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