Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 220547

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
147 AM EDT MON AUG 22 2016

High pressure will build in behind a departing cold front today,
bringing cooler and drier air to the area for most of the week.
Another weak cold front will approach the Western Carolinas from the
northwest toward the end of the week.


As of 1:40 am EDT: While AVL did see a trace of precipitation from
an extremely shallow shower, radar is currently clear following the
passage of a cold front earlier today.  Front is currently analyzed
close to the southeast border of the CWA.  Winds behind the front
are light and northerly.  This flow is lowering dewpoints across the
area tonight.  Drier boundary layer air will lead to lows a little
cooler Monday morning than we have seen in recent weeks, and less
humid and drier weather generally with very low chances for
precipitation and temperatures several degrees cooler than yesterday
and near seasonal normals.


As of 230 PM EDT Sunday:  The short term fcst period kicks off
on Monday evening looking relatively quiet.  An H5 trof axis will
continue ejecting to the northeast across Nova Scotia, while heights
rise over the OH/TN valleys as well as the mid Atlantic states.
At the surface, an old cold front will linger across portions of
the deep south while sprawling cool/dry high pressure settles
over New England on Tuesday, eventually sliding offshore into
Wednesday.  As such, the only chances for precipitation look to
be on the periphery of the high, across the upper Savannah River
valley into the sw NC mtns each day.  Meanwhile another H5 trof
and associated surface cold front will slide south out of Canada,
eventually approaching the OH valley by periods end.  All in all,
the fcst will feature slight/chance pops across the a fore mentioned
zones, while remaining dry elsewhere.  Dewpoints in the lower/mid
60s combined with below normal temperatures should yield fairly
comfortable conditions through the period.


As of 2 PM EDT Sunday: the medium range fcst picks up at 00Z on
Thursday with upper ridging in place over the eastern CONUS and
a closed upper low moving eastward across the US/Canada border.
Over the next couple of days the ridge flattens a bit, after which
the latest model guidance restrengthens it as we move into the
weekend. At the sfc, high pressure will be sliding off the East Coast
and a relatively dry cold front will approach the fcst area from the NW.
The front is still expected to approach the fcst area by late Thursday
and move thru the CWFA on Friday. The deeper moisture associated with
the front remains relegated mostly to the north. Behind the front,
another round of high pressure will settle over the region for the
weekend. No major changes were needed for the sensible fcst with
slight to solid chance POPs over parts of the high terrain Fri, Sat,
and Sun. Temps will steadily warm thru the period with highs starting
out around climatology and ending up at least a category above climo
over the weekend.


At KCLT and elsewhere: At 1 am cold front is analyzed along the
southeast border of the area with light to variable northerly winds
behind it.  Shower activity has ended with the passage of this
front, with no further precipitation expected over the next 24
hours.  Winds will vary some overnight and tomorrow, becoming more
southerly in the afternoon, but will remain light.  With the
northerly flow, dewpoints have been declining across the area and
should remain under pressure overnight. This should largely remove
the chances for fog in the morning.  The low ceilings at some
low-lying areas like KAVL that we have been seeing lately are also
less likely following this change of air mass.

Outlook: The dry air will remain in place across the area resulting
in fair weather through at least mid-week.

Confidence Table...

            05-11Z        11-17Z        17-23Z        23-00Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       Med   62%     Low   48%     High 100%     High 100%
KHKY       High 100%     High  83%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     Med   66%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the scheduled TAF issuance flight rule category. Complete hourly
experimental aviation forecast consistency tables and ensemble forecasts
are available at the following link:




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