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Area forecast discussion 
National Weather Service Miami Florida
606 am EST Friday Feb 12 2016

Aviation...prevailing VFR through forecast cycle. High pressure
overhead keeps the wind generally light, allowing for a sea
breeze to develop today and a land breeze to develop tonight.
Offshore flow leading to north-northeast wind at kapf and north-northwest wind along East
Coast this morning, with sea breeze developing along both coasts
7-9kts after 16z with winds becoming southeast along East Coast and west-northwest
at kapf. The land breeze redevelops overnight, though speeds
generally 3kts or less. /Alm

&&

Previous discussion... /issued 402 am EST Friday Feb 12 2016/

.Nice weather through the weekend, becoming breezy on Sunday...

Discussion...surface high pressure sitting over South Florida
will continue to provide for sunny and dry weather with mild days
and cool nights today into Saturday. Highs today and Saturday will
reach the 70s area-wide with low dewpoints. Some patchy, light fog
is possible over the western interior this morning and again early
Saturday morning, but any fog should be quite shallow and will not
include in forecast at this time.

Impressive shot of Arctic air will invade much of the eastern
third of the country this weekend, but the brunt of the air mass
will stay well north of Florida this time around. The associated
cold front will move through South Florida late Saturday/Saturday
night, but because the main push behind the front is well to our
north, the front will act more like a "backdoor front" with winds
turning to the north-NE rather quickly behind it. This means only a
glancing blow from the Arctic high with only slight cooling
Saturday night and Sunday. Lows will still be in the 40s and 50s
Saturday night, with highs on Sunday in the upper 60s to lower 70s
with a breezy NE wind making it feel a little on the cool side.
Clouds will increase some on Sunday, especially East Coast metropolitan
areas as cold air stratocumulus should be prevalent in the low
level NE flow.

Changes to the weather pattern begin on Monday as a well-defined
middle/upper level shortwave comes out of The Rockies and High Plains
and sweeps across the southeast United States/Gulf of Mexico Monday
night and Tuesday. A 100-120 knots upper level jet will accompany this
feature across the Florida Peninsula. Moisture will gradually
increase across South Florida Monday as low level winds turn to the
se, then S-SW Monday night and Tuesday ahead of an approaching cold
front. This will support showers spreading north across the area on
Monday, with highest coverage of precipitation expected Monday night
into early Tuesday. Models not in perfect agreement on amount of
moisture increase and instability. The GFS moisture return is modest
compared to the European model (ecmwf) which shows a bulls-eye of high quantitative precipitation forecast across
South Florida. Some of this is probably convective feedback and
we've seen the European model (ecmwf) be prone to this with other systems this
winter. However, dynamics are in place to support the possibility of
heavier showers and this will be watched closely in the coming days.
Probability of precipitation for the Monday/Tuesday time frame will show an increase over
the previous forecast and will probably need to be increased further
over the next couple of days as confidence increases in this
scenario. For now will not include thunder, although certainly a
possibility and will largely depend on amount of moisture and
instability.

After the front moves through on Tuesday, dry and seasonably cool
temperatures will return for most of next week, although probably
not as cool as what we've experienced this week.

Marine...good boating conditions expected through Saturday, then
increasing winds and seas Saturday night and Sunday behind the
backdoor cold front. Seas will likely peak at 6 feet in the Gulf
Stream on Sunday. Winds turn to the southeast/south and remain
around 20 knots Monday and Monday night ahead of the next cold
front which will spread showers across the area, with seas
remaining around 6 feet in the Gulf Stream.

Fire weather...dry air today will lead to relative humidity
values below 30 percent across much of the western half of the
peninsula, with higher values in the 40 to 45 percent range over
the eastern half. Light winds today and poor to fair dispersion
will mitigate red flag concerns. Humidity levels will recover some
on Saturday as dispersion values improve to generally good, with
further increase in humidity on Sunday as winds become northeast
to east.

&&

Preliminary point temps/pops...
West Palm Beach 72 55 73 56 / 0 0 0 10
Fort Lauderdale 73 57 74 58 / 0 0 0 10
Miami 73 57 74 58 / 0 0 0 10
Naples 72 54 74 50 / 0 0 0 0

&&

Mfl watches/warnings/advisories...
Florida...none.
Am...none.
GM...none.
&&

$$

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