Area Forecast Discussion
Issued by NWS Miami, FL

Home | 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 291758
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
158 PM EDT MON AUG 29 2016

.AVIATION...

Thunderstorm activity mostly interior and limited at that with
VCSH assigned Atlantic coast terminals through 00z. Thunderstorm
activity could be more active western peninsula this afternoon
with terminal KAPF assigned VCTS at 19Z. Showers and isolated
thunderstorms will continue to stream westward off the Atlantic
terminals and affect the Atlantic coast terminals, with only
isolated thunderstorms expected through 00z. Occasional periods of
MVFR to near IFR conditions may be possible through 00z with
passage of heavy showers or an occasional thunderstorm, will amend
as needed. Deep tropical moisture and additional showers expected
over night with VCSH assigned all terminals at OOZ. Southeasterly
winds around 10 knots or less expected through 06Z then generally
southerly winds around 12z.

60

&&

.PREV DISCUSSION... /issued 1148 AM EDT MON AUG 29 2016/

UPDATE...

Very little was changed in the short term forecast as it is in
line with current forecast trends. Maintained high POPS for
numerous showers and isolated to scattered thunderstorms through
mid morning mainly across the Atlantic waters and coastal zone
then across all the local waters and the peninsula for the
afternoon and early evening hours. Regional wind observations
indicate sustained winds to around 21 knots possible across the
off shore Gulf waters. Given the uncertainties in the forecast
with the presence of Tropical Depression nine, as of 1100 AM about
170 miles west southwest of Key West, maintained the Small Craft
Advisory for the Gulf waters through 00Z this evening, mainly
emphasizing the off shore waters. As for the changes in the
forecast track of Tropical Depression nine, please consult the
products of the National Hurricane Center for the latest
information updated at 1100 AM this morning.

60/BD

PREV DISCUSSION... /issued 748 AM EDT MON AUG 29 2016/

AVIATION...

For the short term...terminals KTMB...KMIA and KOPF could have
periods of MVFR conditions with mainly shower activity over the
next hour with very brief near IFR conditions possible during this
period but low confidence. Otherwise, lightning activity currently very
limited with VCTS assigned Atlantic terminals at 18Z and at KAPF
at 16Z. While winds currently somewhat variable and light, around
13-14Z southeasterly around 10 knots expected and by 18Z around
10-13 knots with higher gusts possible.

60/BD

PREV DISCUSSION... /issued 453 AM EDT MON AUG 29 2016/

DISCUSSION...

Today-Wednesday: Tropical Depression Nine continues to move
through the Florida Straits early this morning. It is currently
forecast to emerge in the southeastern Gulf of Mexico later today,
before turning north-northeast across the eastern Gulf of Mexico
through mid week.

Not much change in the ongoing sensible weather, nor in the
forecast as the influence of TD Nine will keep abundant deep
tropical moisture steaming across South Florida.

Rain/Storms: Squally weather will continue across the region,
especially along Atlantic coast through Tuesday as gusty showers
and thunderstorms move in from the Atlantic coastal waters. Winds
will veer more southerly into Wednesday, which will bring better
rain chances for the Gulf coast as well.

Rainfall totals through mid week may reach 2-5 inches, with locally
higher amounts possible. Currently, the highest rainfall totals
are expected along the Gulf coast closest to the track of TD Nine.
The timing for the threat from the heaviest rains currently is
from late tonight through Wednesday. Heavy rainfall that falls in
a short amount of time may lead to some flooding, especially
areas of poor drainage in urbanized locations.

Winds: Brisk east southeast winds will become southerly into
Tuesday. Expect breezy conditions at times even outside of
storms, with squalls potentially bringing in wind gusts of 40 to
50 mph.

Rip Currents: A high risk of rip currents continues along all Atlantic
beaches over the next few days, along with rough surf. As winds
veer more southerly, the is the potential for an increasing risk
along Gulf coast beaches as well.

Thursday-Next Weekend: The current forecast track of TD Nine has
it moving across North Florida late in the week. South Florida
will remain in a deep tropical airmass through late week, with
breezy conditions and scattered to numerous showers and
thunderstorms each day.

A more typical summer pattern should begin establishing during
the upcoming weekend, although the eventual evolution of TD Nine
will also play a role on the eventual weather scenario. Frequent
lightning and locally heavy rainfall will continue to be the
primary threats.

AVIATION...
Outside of showers and thunderstorms where MVFR/IFR flying
conditions will be possible, VFR flying conditions should prevail
at the TAF sites for much of the TAF period ending 06z Tuesday.
Have gone with VCTS at the TAF sites for much of the period,
except at KAPF where VCTS should hold off until around 16z.
Included a TEMPO group at KMIA, KTMB, and KOPF from 06z-08z to
account for brief MVFR conditions associated with a cluster of
showers moving northwest off the Atlantic waters. After 00z, more
widespread chances for showers and embedded storms will be
possible along with MVFR ceilings.

Winds will be out of the east/southeast around 10 knots through
the TAF period, with higher gusts possible in and around
squalls/thunderstorms.

MARINE...

A Small Craft Advisory remains in effect for the Gulf Coastal
waters through this evening.

Atlantic Waters: East-southeast winds at least 15kts will
continue over the Atlantic waters with 15-20kts possible at times
as TD Nine is forecast to move into the southeastern Gulf of
Mexico later today. For the moment, winds are forecast to veer
more south-southwest into mid week with speeds continuing around
15-20kts. Seas are currently forecast to be around 2-4ft. While
no advisories are currently forecast, conditions will be less than
favorable with very choppy seas.

Gulf Waters: Easterly winds have not been quite as strong as
expected, with forecast trends keeping speeds closer to 15 to 20
knots through today. For now, have left the SCA in place to make
sure these trends hold and given the uncertainties in TD Nine.
Otherwise, the forecast will be similar to the Atlantic waters
with east-southeast winds 15-20kts veering south-southwesterly
into mid week. Sustained winds around 20kts are possible Wed-Thurs
as TD Nine makes its closest approach well west of the area. Seas
3-5 ft, with up to 6 feet at times. However this will likely
continue to fluctuate with changes in the forecast.

Numerous showers and thunderstorms will continue over all the waters
through midweek, with rough seas and locally gusty winds with any
thunderstorm that forms.

&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  76  88  77  90 /  70  90  60  70
Fort Lauderdale  77  89  78  90 /  80  80  60  70
Miami            77  88  77  89 /  70  80  60  70
Naples           78  88  78  88 /  50  80  70  80

&&

.MFL Watches/Warnings/Advisories...
FL...High Rip Current Risk until 8 PM EDT this evening for FLZ168-172-
     173.

AM...None.
GM...Small Craft Advisory until 8 PM EDT this evening for GMZ656-657-
     676.

&&

$$

SHORT TERM...
LONG TERM....
AVIATION...60/BD



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