Area Forecast Discussion
Issued by NWS Greer, SC

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FXUS62 KGSP 230238

Area Forecast Discussion
National Weather Service Greenville-Spartanburg SC
1038 PM EDT SUN MAY 22 2016

Dry high pressure builds into our region from the Mississippi
and Ohio valleys early this week as low pressure lingers over
the Mid-Atlantic. A moist southerly flow develops by mid week and
continues into the weekend.


As of 1030 PM EDT, one last spoke of better upper vorticity rotating
southward into the region is generating continued scattered showers
late this evening - mainly over western NC. Coverage of this
activity will dry up quickly after Midnight as the vort lobe moves
southeast of the area. An isolated rumble of thunder will be
possible, but expect mainly just showers. Northerly winds will
continue to slowly diminish through the night as the pressure
gradient further relaxes. Expect partly cloudy skies overnight with
lows from the upper 40s across the mtns to mid 50s across NE GA.

On Monday, the center of the coastal H5 closed low will drift over
the western Atlantic, but leave cyclonic flow across the Atlantic
states. The circulation around the low should result in greater
cloud cover north of I-40, with the rest the CWA under mostly to
partly sunny conditions. Winds will be much lighter than on Sunday,
remaining from the north through early afternoon before varying.
High temperatures are forecast to range only a degree or two warmer
than Sunday highs.


As of 155 PM Sunday...the early to middle part of the week will see
a slow transition in the upper pattern. The old upper low off the
Mid-Atlantic coast at 00Z Tuesday will move to the New England coast
Monday night and Tuesday allowing a flattening upper ridge to build
in from the west through Tuesday night. No changes to earlier
thinking that surface high pressure will control our weather, which
will be dry with a warming trend back to just above normal Tuesday
and then warming to something on the order of five degrees or so
above normal on Wednesday. If there is an issue, it will be the
chance and extent of convective precip Wednesday afternoon. The
model guidance suggests the better low level moisture will remain
well to our west through the end of the day, so not much coverage is
expected. Cannot rule out a few showers developing over the higher
terrain late in the day, especially the Smokies, so a small PoP will
be carried there.


As of 215 PM Sunday, The forecast models are similar in showing the
upper pattern amplifying late in the week with a trough digging over
the Rockies and plains and ridge building over the east.  At the
surface, high pressure will anchor over the mid-Atlantic near or
over VA as waves of low pressure move NE from the plains to the
Great Lakes with fronts nearly stationary in an arch.  Some energy
and instability affecting the western Carolinas and NE GA as we
remain in the warm sector for several days. Low level wind flow will
be S to SW Friday into Saturday becoming lighter and more variable
late in the weekend.  Instability each afternoon generally along the
values of 1000 to 1500 CAPE mainly over the NC mtns. Wind shear
light.  At the end of this period, the models have the East Ridge
breaking down early next week with GFS showing a tropical low
forming east of FL to start the week then drifting north over the
Carolinas toward mid week. We have days to watch this to see if
other models come onboard.

Max temps mostly in the 80s for lower elevations and Mins in the
60s into weekend then slightly cooler as ridge breaks down.


At KCLT and elsewhere: Lingering scattered showers over western NC
will quickly diminish after 06Z. Isolated thunder chances appear too
small to mention with these showers. Will keep VCSH going at KHKY,
KAVL, and KCLT through 06Z - with the Upstate TAFs dry. Otherwise,
expect mainly SCT to BKN high based stratocumulus with some thinning
overnight in the northerly flow. Northerly winds will continue to
abate overnight. Low end gusts will be possible in the NC piedmont
with mixing again on Monday, but will cap winds at 10 kt or less for
now with continued FEW to SCT high based cumulus/stratocumulus.

Outlook: Mainly VFR conditions will prevail through the week.
Scattered afternoon SHRA/TSRA may return Wednesday, with daily
coverage increasing Thursday and Friday.

Confidence Table...

            02-08Z        08-14Z        14-20Z        20-00Z
KCLT       High 100%     High 100%     High 100%     High 100%
KGSP       High 100%     High 100%     High 100%     High 100%
KAVL       High 100%     High 100%     High 100%     High 100%
KHKY       High 100%     High 100%     High 100%     High 100%
KGMU       High 100%     High 100%     High 100%     High 100%
KAND       High 100%     High 100%     High 100%     High 100%

The percentage reflects the number of guidance members agreeing
with the schedule 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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