Area Forecast Discussion
Issued by NWS Miami, FL

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FXUS62 KMFL 090106

Area Forecast Discussion
National Weather Service Miami FL
806 PM EST Thu Dec 8 2016

The 09/0000Z MFL sounding shows around 1500 J/KG of SB CAPE and
a near record PWAT of 2.10 inches. These values are rather
impressive for December and indicate an ample amount of both
moisture and instability in the atmospheric column. This evening,
radar had depicted moderate to heavy rain showers, which affected
eastern Broward and Miami-Dade counties. With the heaviest cells,
rain rates were as much as 2-3 inches per hour causing isolated
incidents of minor street flooding. Through tonight, as a
stationary front remains planted over the Florida Straits, the
threat for showers and slight chance for thunderstorms will
continue. Short term models, including the HRRR and Hi-Res WRF,
show this activity mainly affecting southern portions of the East
Coast metro and adjacent Atlantic waters. Have adjusted PoPs to
better reflect coverage. Otherwise, forecast appears on track.


.PREV DISCUSSION... /issued 655 PM EST Thu Dec 8 2016/

AVIATION...Ongoing shra affecting east coast from KFLL southwards
with -DZ vcnty KPBI with next frontal boundary. Tempo for MVFR
vsbys and cigs at these sites through 03Z-04Z with potential for
IFR in heaviest activity. Prevailing VFR remainder of tonight, but
potential for occasional MVFR cigs will linger through remainder
of TAF cycle. Winds shift NNW this evening 6-9kts, then becoming
NE 11-16kts with gusts to 20kts for all sites after 15Z.

PREV DISCUSSION... /issued 444 PM EST Thu Dec 8 2016/

DISCUSSION...Latest surface analysis indicated a stationary
boundary sitting along the Florida Straits and a cold front draped
across the central Florida peninsula. Warm, moist, and unstable
air ahead of this front led to spotty shower coverage early today,
but no lightning activity was observed. Light flow near the
surface allowed for a waterspout to develop off the Miami beach
coastline at around 11:30 am this morning.

Current radar trends show scattered convection along a southwest to
northeast oriented line affecting portions of Inland Monroe County
to coastal Miami-Dade. According to the latest HRRR and Hi-Res
WRF runs, this activity will persist through tonight over the
aforementioned areas, as well as the local Atlantic coastal
waters. Enough instability is present to maintain a slight chance
for thunderstorms, but none are expected to become strong. On
Friday, as the cold front continues to push south over our region,
surface winds will shift to the north and northeast. In addition,
drier air will be advected in, allowing dewpoints to fall down
into the 50`s across Collier, Glandes, and Hendry counties, and
low to mid 60`s elsewhere. These values are more typical for this
time of year when compared to the last few days. Cooler air will
also spread across South Florida with Forecast high temperatures
around 10 degrees lower than todays. Similar conditions are
expected on Saturday with northeast flow, cooler weather, and an
enhanced chance of showers along the eastern portion of the

Sunday through early next week, long range models depict a surface
high moving off the coast of Virgina/North Carolina. This feature
will generate a period of east and southeast flow over South
Florida. Sufficient low level moisture will continue the daily
chances of showers, mainly affecting the east coast metro and
interior regions. Maximum temperatures early next week are
forecast in the low to mid-80s, around 5 degrees above normal for
this time of year.

MARINE...An approaching cold front will bring increasing
northerly flow later tonight and into Friday. Winds on Saturday
could reach over 20 knots at times with seas reaching the 7 to 10
feet range, especially over the Gulf Stream. Winds and seas should
decrease from Sunday through early next week.

West Palm Beach  64  72  67  75 /  30  50  50  50
Fort Lauderdale  67  74  65  75 /  50  40  50  50
Miami            67  75  66  77 /  50  40  50  50
Naples           60  69  58  78 /  20  30  10  10



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