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000
FXUS62 KMFL 241130
AFDMFL

Area Forecast Discussion
National Weather Service Miami FL
630 AM EST Thu Jan 24 2019

.AVIATION...
A approaching cold front will bring increasing instability to the
region this morning, allowing for the chances of SHRA and TS to
continue to increase through the morning. Some of the TS may be
strong with gusty wind, and a very slight chance of a tornado,
mainly north of a line from APF over to PBI. The frontal passage
currently looks to be late this afternoon, into the evening
hours. Behind the front, the wind will shift to the northwest for
the overnight hours and subside through the night.

&&

.PREV DISCUSSION... /issued 345 AM EST Thu Jan 24 2019/

..Strong to severe storms possible ahead of cold front today...

DISCUSSION...
A line of showers and thunderstorms is pushing eastward across
the Gulf of Mexico and the Big Bend of Florida this morning. Ahead
of these storms, discrete cells of showers have developed in
prefrontal bands over portions of South Florida. Rain chances will
increase as the morning continues and the front pushes closer. A
healthy low level jet and sufficient surface moisture will be
present this morning into the afternoon over portions of the
state to support strong storms. A special 09z upper air sounding
will soon shed some light on conditions this morning aloft ahead
of the front`s arrival.

Instability and wind shear are present over the region this
morning and expected to remain for portions of the day before the
supporting features shift away. Before that shift of support away
from the region, there is a potential for strong to severe storms.
The primary focus of the strong to severe threat is strong winds,
including tornadic activity. The areas with the higher threat
today are Southwest Florida and the Lake Okeechobee region, which
remain under the Marginal Risk in the Storm Prediction Center`s
Day 1 Outlook.

Current thought is that the line of convection will push into
Southwest Florida this morning and continue eastward, moving
across the east coast metro areas in the afternoon, before
clearing into the Atlantic by the evening. As the low level jet
departs, some weakening in the convection is possible. The coastal
interactions by the convection as it nears the east coast could
provide some localized convergence and shear that could also
produce some stronger storms in the afternoon.

As drier, cooler air moves over the region behind the front for
Friday, there could be some trailing high cloud cover. As the
front stalls to south and east by Saturday, it will act as a focus
for moisture. The next mid-level disturbance will emerge into the
Gulf late Saturday into Sunday, helping to spur the frontal
boundary back northward. This additional moisture will allow rain
chances to increase and the potential for some thunderstorms
cannot be ruled out though the overrunning nature of the cloud
cover may help limit available instability for thunderstorms.

A reinforcing boundary will push through late Monday into Tuesday,
helping to clear out the disturbance and related moisture. A
second frontal boundary on Wednesday will ease into the region
with some divergence in potential solutions causing increasing
uncertainty to end the forecast period. The finer details of this
boundary, its timing, and available moisture could have impacts on
the forecast evolution over time for mid to late week. Currently,
South Florida would remain in the warmer, moist sector capable of
supporting mention of rain chances. If this synoptic setup were
to change, so would the forecast. Preferred the mean of the model
blends for temperatures through the 7 day period.

MARINE...
Increasing showers and storms today as the cold front moves across
the waters. By Friday, the front should be clearing into the
Atlantic with decreasing rain chances over most of the waters. The
dry period will be brief as the moisture returns and a disturbance
moves across the waters Sunday into Monday with additional rain in
the forecast.

BEACH FORECAST...
A high risk of rip currents along the Atlantic beaches today.
Behind the cold front, the Gulf beaches may see an elevated risk
of rip currents on Friday.

FIRE WEATHER...
Drier air behind the cold front on Friday could allow portions of
South Florida to experience relative humidity values in the mid to
upper 30 percent range on Friday afternoon. Wind speeds during the
driest periods of Friday afternoon should remain below critical
thresholds.


&&

.PRELIMINARY POINT TEMPS/POPS...
West Palm Beach  80  56  66  52 /  50  30  10  20
Fort Lauderdale  80  60  67  55 /  40  30  20  30
Miami            80  61  67  56 /  40  30  20  30
Naples           75  56  65  48 /  60  20  10  10

&&

.MFL WATCHES/WARNINGS/ADVISORIES...
FL...High Rip Current Risk through this evening for FLZ168-172-173.

AM...Small Craft Advisory until 7 PM EST this evening for AMZ650-651-
     670-671.

GM...None.
&&


DISCUSSION...02/RAG
MARINE...02/RAG
AVIATION...13
BEACH FORECAST...02/RAG