Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 161757

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
157 PM EDT Sat Sep 16 2017

Weak high pressure will persist across the region into Monday.
Hurricane Jose is forecast to remain over the Atlantic and appears
unlikely to impact the Carolinas or Georgia.  A more summer like
pattern will highlight the weather next week with diurnal rain
chances and above normal temperatures expected.


As of 130 PM EDT: Satellite imagery shows some enhanced cu on the
ridgetops, so once again an isolated shower will not be ruled out,
although nothing appears on radar just yet. Temp trends look good.

Otherwise, 1022 mb surface high pressure centered over the central
Appalachians this morning will continue to nose southward across
our region today through tonight, as Hurricane Jose remains well
east of the GA coastline. Other than the aforementioned shallow
moist layer beneath the mid-level inversion, profiles will remain
relatively dry, with light northerly flow around the high pressure
to the north. The models do continue to produce light QPF along the
eastern slopes of the mountain in weak convergence this afternoon,
but shower coverage should be quite limited given the persistent
mid-level inversion. Will confine any afternoon PoPs to slight
chance along the eastern slopes. Max temps will be about a category
above climo this afternoon, with mins one to two categories above
climo tonight. Another round of mountain river valley fog is likely
late tonight.


As of 200 AM EDT Saturday:  Little change in the short term period
of the fcst as broad deep layer ridging continues to dominate the
synoptic pattern on Sunday morning, while TC Jose remains a few
hundred miles off the Carolina coastline.  Jose looks to continue
tracking northward leading to virtually no impact for northeast GA
and the Carolinas, other than reinforcement of the drier nely flow
thanks to the northeast surface high.  Otherwise, a cold front
associated with an Upper Midwest shortwave will extend southward
through the Plains states.  Pattern evolution on Sunday and Monday
is rather uneventful as the only thing to note is the persistence of
the deep ridge, and further northward advancement of Jose, possibly
posing some threat to the New England shores.  As for the fcst
closer to home, token below climo pops over the high terrain, dry
elsewhere with temperatures returning to near or slightly above
normal levels amongst abundant sunshine.


As of 100 PM EDT Saturday: Continued above normal temperatures are
slated for Wednesday with the cwfa oriented within the eastern
periphery of the llvl return flow moisture.  In concert with
encroaching s/wv energy, diurnally fired deep convection remains
possible for the mtns.  The sensible weather atop the region may not
change a whole lot for Thursday with what is shaping up to be a
pretty weak flow regime lingering acrs the SE conus.  Ridge axis
center remains progged to strengthen atop the NE conus throughout
the latter half of the period.  The accompanying increase in
easterly flow/atlantic moisture influx atop the Carolinas will allow
temperatures to return to near climo by Saturday. The extended range
guidance is giving mixed signals with respect to any increase in
shower activity Friday and Saturday, but the consensus keeps
probablities in the low chance range through the end of the period.


At KCLT and Elsewhere: As expected, fair weather cu have developed
across the region this afternoon, with cloud bases generally around
040-045. Will not rule out a temporary ceiling as clouds drift
slowly overhead, so have elected to include a TEMPO group for BKN
clouds. Any ridgetop showers should avoid KAVL. The clouds should
thin out around sunset. Wind will remain light and generally from
the N. Persistence is a good forecast for the next 24 hours. Thus,
expect another round of valley fog/stratus tonight at KAVL,
with conditions deteriorating after midnight to at least low
IFR for several hours before daybreak, then lingering until 14Z
before burning off. Other sites should be spared any prevailing
restrictions. Wind will come up light NE after sunset and more cu
will form around midday Sunday.

Outlook: Isolated, mainly high terrain diurnal showers will continue
through the late weekend into early next week. Morning mountain
valley fog/stratus are also expected each day.

Confidence Table...

            18-24Z        00-06Z        06-12Z        12-18Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High  97%     Low   57%     Med   75%
KHKY       High 100%     High 100%     High  97%     High  97%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High  97%

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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