Area Forecast Discussion
Issued by NWS Miami, FL

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS62 KMFL 202347 AAA
AFDMFL

Area Forecast Discussion...UPDATED
National Weather Service Miami FL
747 PM EDT Thu Sep 20 2018

.UPDATE...
Most of the showers and thunderstorms have dissipated this evening
over South Florida, except over the interior areas and the Gulf
waters of South Florida where a few showers are still ongoing.
These showers should continue to slowly dissipate through rest of
the evening hours, as isolated to scattered showers and a few
thunderstorms should develop in the Atlantic waters and move
westward towards the east coast metro areas. The showers and
thunderstorms should continue to increase in coverage after
midnight over the Atlantic waters and work into the east coast
metro areas before dissipating, as the mid to upper level low over
the Bahamas moves westward towards South Florida. Therefore, pops
will remain isolated over the interior and west coast metro areas
this evening, while the east coast metro areas will see isolated
showers and thunderstorms after midnight.

Rest of the forecast looks good at this time and no other changes
are planned.

&&

.AVIATION...
Few shower may linger for an hour or two for KAPF, then generally
dry conditions will prevail overnight. After daybreak, scattered
activity should develop as relatively early sea-breeze boundary
intrudes into eastern terminals, for now will go with 14-22z VCSH.
Gulf breeze will be later in afternoon for Naples, when VCSH also
in place. Generally light winds overnight with E wind around 10
KT during the day. NW Gulf breeze by mid- afternoon is forecast at
KAPF.

&&
.UPDATE...54/BNB
AVIATION...23/SBK

.PREV DISCUSSION... /issued 412 PM EDT Thu Sep 20 2018/

..A FEW STRONG STORMS POSSIBLE FRIDAY...

..AN INCREASE THREAT OF RIP CURRENTS BEACHES OF PALM BEACH COUNTY
THIS WEEKEND...

DISCUSSION...
High pressure over the Southeastern United States will remain
nearly stationary this weekend keeping an light easterly wind flow
over South Florida leading to the typical scattered to numerous
sea breeze driven showers and thunderstorms each day with the best
coverage over the interior and west coast metro areas.

An upper level low will also continue to develop over the Bahamas this
afternoon and move westward across South Florida late tonight into
Saturday. This will allow for the 500 mb temp to cool down to -8
to -9C leading to a few strong storms on Saturday especially where
the sea breezes collide. The primary impacts from the strong storms
will be gusty winds, hail, frequent lightning strikes, and locally
heavy rainfall.

The upper level low will then move into the Gulf of Mexico on
Sunday allowing for the 500 mb temps to warm back up to around -6C
which is near normal for this time of year. Therefore, the
thunderstorm activity on Sunday should be more of a typical
summertime weather pattern with lightning strikes and some heavy
rainfall across the region.

Extended forecast...
The high will remain nearly stationary early of next week over
the Southeastern United States before shifting a little bit south
into Central Florida for the middle of next week as a cold front
moves southward into the Southeastern United States from the
north. This will allow for the light easterly winds early next
week to become more of a south/southeast direction by middle of
next week over South Florida. Therefore, isolated to scattered
showers and thunderstorms will continue over the region with the
best coverage over the western areas early next week shifting to
the Lake Okeechobee region for the middle of next week.

MARINE...
The winds will be easterly around 5 to 10 knots this weekend into
early next week over South Florida Waters. At the same time, a
small northeast swell around 2 feet will be working into the
Atlantic waters of Palm Beach County from the north that is
associated with the low north of Bermuda. This will allow for the
Atlantic seas to build from less than 2 feet tonight to 2 to 4
feet by this weekend, except for the Palm Beach Atlantic waters
where the seas will build to 3 to 5 feet. The Gulf seas will
remain at 2 feet or less this weekend.

BEACH FORECAST...
The threat of rip currents should increase this weekend along the
beaches of Palm Beach County due to the small northeast swell
working into these waters this weekend. Rest of the Atlantic
beaches of South Florida and the gulf beaches of South Florida
should remain in the low condition at this weekend at this time.
&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  77  90  77  90 /  30  40  20  20
Fort Lauderdale  79  89  79  89 /  30  40  20  20
Miami            78  90  78  90 /  20  40  20  30
Naples           75  91  75  91 /  10  60  30  60

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...None.
AM...None.
GM...None.
&&

DISCUSSION...54/BNB
MARINE...54/BNB
AVIATION...23/SBK
BEACH FORECAST...54/BNB



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.