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Area forecast discussion 
National Weather Service Miami Florida
406 am EDT Wednesday Oct 1 2014

Highlights:
* typical afternoon tstorm development through Saturday, focusing
interior and East Coast metropolitan.
* First taste of fall (south Florida style) looking more likely by
Sunday!

Discussion...a surface trough lies across central FL, placing
South Florida in a moist west-SW wind flow again today and this will
continue through Saturday. So am expecting a typical diurnal
pattern of convection, favoring the interior and East Coast given
the westerly component of the wind fields. The lower level winds
today still look just breezy enough to prevent a full fledged
Atlantic sea breeze from developing, but winds do look to back to
a more southerly direction this afternoon, providing enough
convergence to activate numerous thunderstorms. The main impacts
will be lightning strikes along with the potential for isolated
street flooding where the heaviest storms develop. This similar
pattern will repeat itself through the first half of the upcoming
weekend as precipitable waters remain near 2 inches in a typically unstable
atmosphere.

A significant change in the weather is looking more likely for the
later part of the weekend as now both GFS and European model (ecmwf) are sending the
first strong cold front of this fall season across South Florida
Saturday night and off our coast Sunday morning. GFS ensembles are
supporting this frontal passage idea as well...with the average of the
members a degree or two below the operational GFS MOS Sunday and
Sunday night. Given this...have trended the forecast cooler Sunday
through Tuesday. This would be a very noticeable change from the
sultry high dewpoints we've felt since may...well into the 70s.
Behind the front, dewpoints will fall into the 60s on a nice
northerly breeze. Highs on Sunday are forecast to be only in the
Lower-Middle 80s. Lows are forecast to drop into the 60s interior
and Gulf Coast both Sat and Sun night...and lower 70s East Coast
metropolitan with comfortable humidity...letting US know that it is
indeed fall.

This is pretty early in the season for a cold front, but the
pattern of an amplified trough across the eastern Continental U.S. Does not
seem to want to let go as the trough continues re-establishing
itself even after temporary flow changes. Given this, an early
season cold front isn't shocking...and in fact the longer range
GFS shows another cold front as we enter middle October. Could this
be the beginning of a parade of cold fronts? Too early to say,
but i'm inclined to believe so given the aforementioned locked
synoptic pattern. /Gregoria

&&

Marine...prevailing winds will be less than 10 knots through Friday
with correspondingly low seas. The first strong cold front of the
fall season is looking more likely to sweep across the local
waters Saturday night with winds becoming northerly then
northeasterly behind it along with increasing seas, especially off
the Palm Beach coast. /Gregoria

&&

Preliminary point temps/pops...
West Palm Beach 88 76 87 77 / 70 30 50 20
Fort Lauderdale 88 78 88 77 / 60 30 70 20
Miami 89 77 88 77 / 60 20 70 20
Naples 86 78 87 77 / 40 20 30 10

&&

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

$$

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