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fxus62 kmfl 270834 
afdmfl

Area forecast discussion
National Weather Service Miami Florida
434 am EDT Sat may 27 2017

..hot Memorial Day weekend...

Discussion...
near-term (this morning): diffuse frontal boundary over the
Atlantic extending to the Southeast Florida coast along with a passing
mid-level shortwave trough are helping to trigger showers and
thunderstorms near and just east of the Upper Keys early this
morning. Expect this activity to remain over the Gulf Stream
through the morning hours, with mostly clear skies over the
peninsula.

Short-term (today through Memorial day): the Memorial Day weekend
will be a hot and mainly dry one across South Florida as high
pressure aloft builds into the area. For today, there will be just
enough influence from the diffuse front and passing mid-level
shortwave trough to favor a few showers and thunderstorms this
afternoon primarily over interior sections south of Lake
Okeechobee as well as the East Coast Metro area south of West
Palm Beach. Sea breeze collision will be over the interior, with
the low/mid level flow moving any showers and storms slowly
towards the East Coast. Went with similar pops as the previous
forecast, which is higher than MOS and close to the model
consensus. As the high pressure aloft builds into Florida Sunday
and Memorial Day, deep-layer drying will be more pronounced,
thereby further reducing rain chances. An isolated afternoon storm
or two over the southern everglades is about all that is in the
forecast for the end of the Holiday weekend.

High temperatures through Memorial Day will rise into the lower
to mid 90s, except for coastal areas which will top out in the
upper 80s. 1000-850 mb thickness increase to over 1430m over
interior sections each afternoon, which should easily support mid
90s with a few upper 90s possible. Even the western suburbs of
the Miami-Fort Lauderdale-West Palm Beach Metro may reach the mid
90s, especially on Sunday. Afternoon sea breezes will mitigate the
heat over Metro areas, but not provide much relief over interior
sections. Heat index values are forecast to reach 100-102 degrees
over most of Metro Southeast Florida today, and around 100 degrees Sunday
and Memorial Day. Despite warmer daytime temperatures, heat index
over interior sections will likely fail to reach 100 degrees due
to low relative humidity values. Minimum temperatures will be
in the sultry mid 70s East Coast Metro, but cool down into the
upper 60s interior sections tonight and possibly again Sunday
night as dry air and clear skies promote some radiational cooling
and temporary relief from the daytime heat.

Long term (tuesday through Friday of next week): high pressure
surface and aloft will shift east into the Atlantic, leading to
prevailing and humid east/southeast wind and a pattern reminiscent of
Summer. This pattern favors night and morning showers/isolated
thunderstorms Atlantic and East Coast and afternoon and evening
showers/thunderstorms interior and Gulf Coast. Temperatures will
be close to average for the end of may and beginning of June, with
highs in the upper 80s to lower 90s and lows in the 70s.

&&

Marine...
as the high pressure remains over South Florida through the
Memorial Day weekend, winds will be largely driven by sea breezes.
Light wind at night and morning will increase to near 15 knots
during the afternoon sea breeze cycle near shore. More steady
east/southeast wind beginning Tuesday as the high pressure area
shifts north and east. Seas will be mainly 3 feet or less.

&&

Beach forecast...
light winds in the morning will increase some each afternoon with
the sea breeze cycle, but overall surf conditions should be rather
benign. Isolated thunderstorms possible this afternoon East Coast
beaches, otherwise mostly dry conditions through the Holiday
weekend.

&&

Fire weather...
dry air which filtered into the Lake Okeechobee area yesterday
behind the weak front will linger over the next 2-3 days, leading
to low relative humidity values well below 40 percent over most of
interior South Florida through Memorial Day. Driest air expected
today as relative humidity values will drop to below 30 percent
over parts of Glades County. As a result, a red flag warning has
been issued for Glades and Hendry counties this afternoon into
early evening. Relative humidity values remain near critical levels Sunday,
lowering to below 40 percent even into interior portions of
Southeast Florida, then slowly moderate Memorial Day into early
next week.

&&

Previous discussion... /issued 149 am EDT Sat may 27 2017/

Aviation...
VFR conditions should prevail, although very brief periods of
sub-VFR stratus is possible over Miami-Dade and Broward terminals
through about 12z. Isolated afternoon thunderstorms also possible
over these locations, but pop too low to warrant mention in taf
at this time. Light winds will persist until midday seabreezes penetrate
each coast, bringing onshore wind at around 10 knots. Wind will
diminish again tonight.

&&

Preliminary point temps/pops...
West Palm Beach 91 75 92 75 / 10 0 10 0
Fort Lauderdale 90 78 91 77 / 20 10 10 0
Miami 93 77 93 77 / 20 10 10 10
Naples 89 74 89 75 / 10 0 0 0

&&

Mfl watches/warnings/advisories...
Florida...red flag warning from noon today to 8 PM EDT this evening for
flz063-066.

Am...none.
GM...none.
&&

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