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Area forecast discussion 
National Weather Service Miami Florida
1237 PM EST sun Feb 1 2015

Aviation...

East to southeast flow continues with broken/overcast ceilings around 5kft this
afternoon. Some gusts to 25 kts. Diurnal cumulus will dissipate this
evening although other clouds will still move onshore overnight.
Outside chance of brief MVFR ceilings with any showers that develop
along the East Coast around dawn. Ch too small for vcsh at this
time. In advance of monday's front, surface winds veer to the S
and SW, with the best chance of showers at apf.

&&

Previous discussion... /issued 1001 am EST sun Feb 1 2015/

Update...
not much change is necessary on the morning updates. The Small Craft Advisory for
the offshore Gulf waters will be allowed to expire as the 06z run
of the hires model guidance continues to show the southeast wind
to lessen over that area this morning. Current surface analysis
shows a stationary frontal boundary over the Florida Straits just
off the north coast of Cuba stretching into the central Gulf of
Mexico with a surface high pressure centered just off the
Carolinas coast. The high pressure will continue to shift east
into the Atlantic through the afternoon resulting in the surface
wind to veer to the southeast. The 12z mfl sounding indicates a
very stable atmosphere in place with virtually no chances of a
shower developing. Current temperatures are around 70 with a few
locations reaching the lower 70s. Plenty of sunshine despite of
scattered low level cumulus will allow for afternoon temperatures to
reach the middle to upper 70s.

Kob

Previous discussion... /issued 701 am EST sun Feb 1 2015/

Aviation...

Cumulus field around 5kft once again expected today, with east to southeast
winds gusting to 25 kts at times this afternoon. Surface high
pressure will continue moving away from the eastern Seaboard.
VFR conds will persist.

Previous discussion... /issued 403 am EST sun Feb 1 2015/

Short term (today-tuesday)...

Recently animated water vapor imagery showed a shortwave trough
digging east-southeast across the plains states and more of a zonal
pattern/broad ridging across the eastern half of the country. The
latest surface analysis showed high pressure centered over the Carolina
coast and a frontal boundary extending east-southeast from the western Gulf of
Mexico to the Florida Straits/northern Cuba. Early morning observations
across South Florida showed moderate easterly winds with
temperatures ranging from the lower 50s over the interior/Gulf Coast
to the middle to upper 60s along the East Coast. Despite the dry surface
and middle-level air in place in the wake of a cold front that moved
through yesterday morning, a sufficient amount of boundary layer
moisture beneath a subsidence inversion will continue to support a
shallow cumulus field with bases in the 4-5 kft range this morning/today,
especially over the East Coast/metropolitan locations. Although a
warming/moistening trend will be expected into the upcoming week,
another pleasant day is expected today as dewpoints remain in the
middle to upper 50s (high temperatures reaching the low 70s this
afternoon).

The latest short-range model guidance has initialized the current
pattern well and shows low pressure developing over the lower MO
valley in response to the upper trough over the plains today. This
surface/upper feature will quickly translate east-northeast toward the northestern
states through Monday with a trailing cold front sweeping eastward
across the southern states tonight and through South Florida Monday
evening/night. The low-level flow across South Florida will
steadily veer to the southeast today, south tonight and southwest
through the day Monday ahead of the approaching frontal boundary.
Southerly flow, increasing moisture and isentropic lift ahead of
this approaching boundary could result in a few showers through
the day Monday. The latest arw/nmm model reflectivities show
mainly a narrow line of showers along/ahead of the cold front
moving into the northwestern areas from Naples to the lake region Monday
afternoon/evening periods. The consensus guidance continues to
indicate temperatures reaching the low 80s (average is around 76
deg) across the interior and East Coast areas with the SW flow in
place.

Much drier air will filter into the local area in the wake of the
cold front Monday night through Tuesday. Dewpoints are prognosticated to
return to the middle 40s across the interior areas to around 60 degree
along the Southeast Florida coast. Afternoon highs are forecast to
dip back into the low to middle 70s on Tuesday.

Long term (tuesday night-Saturday night)...

The extended guidance remains in decent agreement through the middle-
week period and indicates the progressive pattern continuing. The
ensemble guidance remains persistent overall from cycle to cycle and
shows a southern stream shortwave trough translating eastward along the northern
Gulf Coast region and phasing west/ the northern stream as another
shortwave trough dives southeast over the region from the northern
plains. This upper energy will induce cyclogenesis over the
western Gulf of Mexico through the day Wednesday.

Although differences between the model solutions begin to emerge
through this period, a general consensus indicates this surface
reflection quickly progressing eastward over the Gulf of Mexico and
dragging a cold front across the Florida Peninsula sometime
Thursday night into Friday. The European solutions are slightly
more bullish with the development of the Gulf low and faster than
the GFS through this period. Temperatures will remain at or above
average through the period ahead of the Gulf low/frontal boundary
and possibly back to around normal by Friday night/Saturday
morning with dry conditions expected over the weekend.



Marine...

The latest marine package was updated to include Small Craft Advisory winds over the
offshore Gulf waters, which was based on an evening ascat pass that
showed 20-25 knot winds over the southeastern Gulf of Mexico. The latest
hires model guidance supports around 20 knots winds over the far
offshore Gulf waters through daybreak, then gradually shows a
weakening trend through the morning and afternoon period as the
gradient weakens and the flow shifts to the southeast. Exercise caution
conditions will likely continue over the Atlantic waters today
with east-southeast flow continuing.

High pressure will continue to shift east through Monday as a cold
front sweeps eastward across the Gulf of Mexico. The cold front will move
across the local marine areas Monday night with high pressure
building behind the front through the middle of next week. Later in
the week, a Gulf low is prognosticated to develop over the western Gulf and
track eastward over the Florida Peninsula. Despite the model differences,
the European model (ecmwf) and GFS solutions indicate a significant northerly wind
field setting up along the East Coast in the wake of this system
Thursday night through Friday with north-northwest flow Friday into Saturday
across South Florida. If this scenario evolves, a moderate to
large northerly swell would become a possibility by next weekend.
However, due to the differences noted and this being toward the
end of the forecast period, forecast confidence remains low at
this time and later model cycles will need to be monitored.

The latest probabilistic rip current guidance indicates hazardous
rip currents will remain likely today along the East Coast beaches
from Jupiter Inlet to Miami. As a result, the high risk of rip
currents will continue.



&&

Preliminary point temps/pops...
West Palm Beach 67 83 59 74 / 10 30 20 10
Fort Lauderdale 67 81 62 73 / 20 20 10 10
Miami 68 83 62 76 / 10 20 10 10
Naples 62 77 54 71 / 0 30 20 10

&&

Mfl watches/warnings/advisories...
Florida...high rip current risk until 7 PM EST this evening for flz168-172-
173.

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

$$

Short term...30/kob
long term....30/kob
aviation...21/km

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