Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Miami Florida
848 PM EDT Monday Oct 20 2014

Update...precipitable water on the evening Miami sounding increased a full inch
since this morning...and confirmed by GPS met data and sits now at
near 2" at Miami...up from 0.91 inches this morning! This abrupt
moisture surge induced tstorm development along the Miami-Dade
coast late this afternoon/evening with areas near Cutler Bay
receiving over 6"! Street flooding occurred across this area
before the storms rolled off the coast. Additional development is
now occurring again across the far southern peninsula and slowly
lifting northward. So kept probability of precipitation in for the overnight with the
highest probability of precipitation across the south. /Gregoria


Previous discussion... /issued 752 PM EDT Monday Oct 20 2014/


Shws and a few storms which affected mia and nearby terminals have
weakened and departed offshore. Showers may redevelop later, as
they redevelop over the floirda straits tonight, so after a break
vcsh was used. Additional moisture combined with a few upper level
disturbances entering from the eastern Gulf of Mexico, will lead
to more numerous showers and thunderstorms on Tuesday. Thunderstorms in the vicinity may be
necessary with the next set of tafs.

Previous discussion... /issued 355 PM EDT Monday Oct 20 2014/

Possible wet conditions and heavy rainfall late this week...

Short term...

Tonight through Wednesday...
high pressure over the southeastern United States will move east
into the Atlantic waters tonight into a middle to upper
level trough over the Great Lakes moves east into the Middle Atlantic
States. Low pressure will then close off near the Middle Atlantic
States Tuesday night into Thursday pushing a cold front southward
from the Tennessee Valley to the Lake Okeechobee region before
stalling out.

The steering flow over South Florida will also swing from an
easterly direction tonight to a southwest direction by Wednesday
allowing for tropical moisture to work into the region from the
south. Therefore...probability of precipitation over South Florida will be raised to
scattered to numerous during this time frame with the highest probability of precipitation
over the southern areas.

Wednesday night into Thursday...
south Florida's weather will depend on the development and
movement of the tropical disturbance over the southwest Gulf of
Mexico. At this time...NHC is thinking that the disturbance will
move eastward into the western Caribbean Sea along with deep
tropical moisture.

The stationary front will also remain over the Lake Okeechobee
region during this time frame which will keep the surface winds
in an easterly direction. This weather pattern will allow for good
isentropic lift over South Florida. Therefore...the probability of precipitation will
remain in the 50 to 70 percent range over South Florida for late
this week with the best coverage over the southern areas.

There could also be some heavy rainfall over South Florida late
this week if this weather pattern sets up.

A few of the storms could even become strong to severe over South
Florida late this there is also a middle to upper level jet
that will be working over South Florida from the west.

Long term...
the European model (ecmwf) long range model is showing that the disturbance will
stall over the Bahama Islands this weekend before moving back west
early next high pressure builds over the western
Atlantic waters. The GFS long range model is showing that the
disturbance will remain nearly stationary over the western
Caribbean this weekend before moving northward into the Gulf of
Mexico early next week.

As you can see from the long range models...there is very low
convenience in the forecast for this weekend into early next
week. So will not change the extended forecast at this time...and
will continue to monitor the latest runs of the GFS and European model (ecmwf) and
guidance from NHC.

Therefore...South Florida residents and visitor need to continue
to pay attention to the latest forecast from the National Weather
Service in Miami Florida through the week and into this weekend.

the winds will be easterly tonight into Wednesday with speeds of
15 knots or less. For late this week into this weekend..the wind
speeds and direction will depend on the strength and location of
the disturbance in the Gulf of Mexico.


Preliminary point temps/pops...
West Palm Beach 71 84 71 84 / 30 50 50 40
Fort Lauderdale 76 84 76 84 / 40 50 50 50
Miami 74 85 74 85 / 50 50 50 60
Naples 70 85 70 85 / 30 50 40 50


Mfl watches/warnings/advisories...


National Weather Service Glossary of Abbreviations