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Area forecast discussion 
National Weather Service Miami Florida
1009 am EDT Sat Jul 30 2016

Update...
12z mfl sounding data describes a more stable air mass compared
to yesterday, with morning cape of less than 700, a little warmer
500 mb temps around -6 c, and fzl above 16 kft. However, the
modified sounding values still suggest enough thermodynamic
instability will be in place this afternoon as daytime heating
peaks for some storms to form. Latest local hi-res model
solutions also suggests potential for at least scattered
afternoon thunderstorms and continuing through the early evening
hours. Best chances of rain remain over interior and Gulf Coast
areas where numerous storms could develop later today. Current
forecast package remains on track and no significant changes are
required for the morning update.

&&

Previous discussion... /issued 812 am EDT Sat Jul 30 2016/

Aviation...
VFR prevails at all terminals this morning. Current prevailing
light and variable winds will transition into onshore flow early
in the afternoon as sea breezes develop. Kept carrying thunderstorms in the vicinity for
all terminals during the afternoon hours with VFR continuing
outside of any thunderstorm that may affect a terminal or its
vicinity.

Previous discussion... /issued 349 am EDT Sat Jul 30 2016/

Discussion...
models continue to show a fairly typical summertime pattern for
South Florida for at least the next week. A Bermuda high continues
to maintain its presence in the western Atlantic. At 500mb, the
pattern is fairly stagnant, with a ridge sitting over the central
US, and weak flow across the Florida Peninsula. This will keep a
warm, but fairly seasonable air mass over the County Warning Area. The temperature
gradient between the air mass over the water and over the Mainland
during the day, looks to Max out right around 6f. This is barely
enough for a sea breeze to take shape, if at all. It will likely
continue to act as it has been over the last few days, with a sea
breeze front setting up over the Atlantic coast, allowing for some
showers and storms to develop over the Southeast Florida Metro
area. They will then then propagate towards the interior through
outflow boundaries, and diurnal heating in the interior.

The last couple of soundings continue to show the freezing level
well above 15k ft, almost 16k ft, and the 500mb temp around -6c
to -6.5c. This supports a persistent pattern for the next couple
of days, with showers and thunderstorms possible, mainly in the
interior and along the Gulf Coast, with a few still possible along
the Atlantic Metro areas. Some strong gusty wind will be possible,
and some heavy rain, as pwats are around 2 inches.

There will, of course be some fluctuations through the week in
moisture. Probably the most significant will be an influx of
tropical moisture on Sunday, as a wave move by to the south. This
will allow for an increase in instability as well, leading to
better coverage of convection across the area, as well as possibly
somewhat stronger convection, depending on the exact dynamics that
fall into place. Then conditions dry out for a day, before another
influx of moisture and instability, which will enhance convection
across the County Warning Area on Tuesday as well. Behind this wave, the pattern
looks to become stagnant once again, with typical diurnal showers
and thunderstorms over the Mainland and nocturnal convection over
the coastal waters.

Aviation...
calm and variable winds will prevail through the early morning
hours as high pressure builds into S Florida today. A few isolated
showers could develop near the terminals by mid morning with southeast
winds picking up to around 10 knots with daytime mixing. Sea
breeze convection is expected to develop early afternoon along the
coast and move further inland into the day. Added thunderstorms in the vicinity for pbi,
fxe, tmb and apf where the higher chance for thunderstorms is
possible. Winds will decouple in the evening hours and remain
light through midnight.

Marine...
showers and thunderstorms will continue to be possible across the
South Florida waters through the middle of next week. Coverage may
be enhanced Sunday and then again on Tuesday as a couple of
tropical waves move across the area, bringing an influx in
moisture and instability. With the wave on Tuesday, the wind is
forecast to increase out of the east, which will allow seas to
build in the Atlantic to around 3 to 4 ft for Tuesday and
Wednesday. For the next couple of days, the rip current risk
should be low for all South Florida coastal areas, as the east
wind remains below 10kts. By the middle of next week, the risk
may increase as the easterly wind increases.

&&

Preliminary point temps/pops...
West Palm Beach 92 79 90 80 / 20 30 60 10
Fort Lauderdale 91 79 90 81 / 20 30 60 10
Miami 93 79 91 81 / 30 30 60 10
Naples 91 76 91 76 / 40 30 60 20

&&

Mfl watches/warnings/advisories...
Florida...none.
Am...none.
GM...none.
&&

$$

Short term...
long term....

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