Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

fxus62 kmfl 171128 
afdmfl

Area forecast discussion
National Weather Service Miami Florida
628 am EST Fri Nov 17 2017

Aviation...
VFR conditions will prevail into Saturday. Light offshore flow (nw
for eastern terminals) will transition from 14-16z to NE at 10-14
knots. This evening, wind will again less to speeds around 5 knots.
Direction overnight is reflected as NE, but there is reasonable risk
of northwest flow again setting up over the East Coast.

&&

Previous discussion... /issued 357 am EST Fri Nov 17 2017/

Discussion...
today through the weekend: lingering low level moisture and a few
showers will affect mainly East Coast areas this morning, but
drier air over central Florida will make steady southward progress
today and overspread all of South Florida by afternoon. This sets
the stage for a mainly dry and sunny weekend as the surface high
pressure area over the eastern United States shifts east into the
Atlantic. A cold front will move down the peninsula on Sunday and
reach the Lake Okeechobee area late in the afternoon, then through
the rest of South Florida Sunday evening. Air ahead of the front
during the day on Sunday will be too dry to support any
precipitation, with isolated to scattered showers accompanying and
following the frontal passage mainly Sunday evening and night.

Breezy NE wind today will decrease in time for the weekend. Along
with the drier air, overnight and early am low temperatures will
be a touch cooler this weekend, ranging from the upper 50s
interior SW Florida to the 60s elsewhere. High temperatures will
range within a few degrees either side of 80 degrees. In essence,
temperatures continuing to run very close to average for mid-
November.

Monday through Thanksgiving day: weather becomes unsettled for
Thanksgiving week as the front is expected to stall over The
Straits of Florida on Monday. As surface/low level winds turn NE
and east on Monday, clouds and scattered showers will affect East
Coast areas while the interior and Gulf Coast squeeze out one more
dry day. A longwave trough looks to set up over the central and
eastern United States as the week progresses, with a strong
shortwave trough coming out of The Rockies and sweeping into the
Gulf of Mexico on Wednesday. The front should respond to the
deepening trough by backing up over South Florida and spreading
increasing clouds and precipitation over the area. Included a
slight chance of thunderstorms on Tuesday as enough instability
should be in place. Consensus of model guidance has the shortwave
trough deepening into a closed low pressure system on Wednesday
slowly progressing eastward, with the European model (ecmwf) continuing its trend
of a stronger surface and mid-level low than the GFS. A composite
of the global model guidance points the front becoming nearly
stationary over central Florida as the closed low in the Gulf
moves slowly east through Thanksgiving day. This scenario should
keep rain chances fairly high Wednesday through Thanksgiving day,
but with low confidence in the details of the evolving pattern
next week, wouldn't be surprised to see changes in timing and
coverage of any precipitation over the next few days. Temperatures
start off on the cool side Monday morning in the 50s over the
interior, otherwise lows in the 60s to around 70 and highs around
80 to the lower 80s will be the rule for much of Thanksgiving
week.

Marine...
small craft caution today Atlantic waters for NE wind 15-20 knots
and seas to 6 feet. Wind and seas subside late tonight, with
decent boating conditions this weekend. A NE swell of 2 feet will
linger over the Atlantic waters through Sunday. Wind and seas
increase late Sunday night with the passage of the cold front,
with caution or perhaps even advisory level conditions possible
early next week over all local waters, along with increasing
showers.

Beach forecast...
a high risk of rip currents will continue today at the Atlantic
beaches with NE wind of 15-20 mph. The rip current risk will
slowly diminish on Saturday but likely remain elevated, before
lowering further on Sunday.
&&

Preliminary point temps/pops...
West Palm Beach 79 64 81 63 / 10 10 10 10
Fort Lauderdale 80 69 81 67 / 30 10 10 10
Miami 80 68 82 67 / 30 10 10 0
Naples 80 61 81 63 / 10 10 0 0

&&

Mfl watches/warnings/advisories...
Florida...high rip current risk through this evening for flz168-172-173.

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

National Weather Service Glossary of Abbreviations