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fxus62 kgsp 240132 
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Area forecast discussion 
National Weather Service Greenville-Spartanburg SC 
932 PM EDT Wednesday Jul 23 2008 


Synopsis... 
a cold front will move across the western Carolinas and northeast 
Georgia tonight. Dry high pressure will build in Thursday and 
Friday. The front will move back into the region on Saturday and 
become stationary as a series of upper lows move across the area. 


&& 


Near term /through Thursday/... 
widespread locally robust thunderstorms around kclt and points eastward 
will diminish through late evening...but will hang onto isolated 
covering all across the Piedmont into the overnight hours as DPVA slug 
from upper trough swings through and works on lingering 
moisture. Otherwise...expect the clearing trend to spread 
east from the tenn line. Surface boundary to settle south across 
the County warning forecast area ushering in min temperatures below seasonal normals. 
Dry and stable air is expected for Thursday and no probability of precipitation will be 
carried with maximum temperatures slightly below normal. 


&& 


Short term /Thursday night through Saturday night/... 
as of 215 PM Wednesday...looking at bukfit soundings from the NAM 
and GFS...the airmass over the western Carolinas and NE Georgia should 
remain stable Thursday night and Friday. I did keep some slight chance probability of precipitation 
in the NC mountains late Friday and Friday night...as a little instability is 
shown by the models starting in the early evening hours over the 
high terrain. The airmass will gradually moisten over the mountains 
on Saturday. The old European model (ecmwf) brought an mesoscale convective system...or perhaps the remnants 
of one...across the northern part of the forecast area Sat morning. The GFS also 
brings the remnants of a northwest flow mesoscale convective system over the forecast area on Sat...but 
farther to the south and a little earlier in the day. Having both 
models bring something through the area is a good sign...as are the 
high probability of precipitation on the sref...but confidence on the timing or exact nature 
of the precipitation is still not very high. For now will carry 30 probability of precipitation 
outside the mountains and 40 to 50 probability of precipitation over the mountains through the 
day on Sat. With the eastern Continental U.S. Long wave beginning to amplify 
again...the northwest flow will strengthen a little Sat night. 
Therefore...I/ve kept chance probability of precipitation in the forecast well into the 
nighttime hours. 


&& 


Long term /Sunday through Wednesday/... 
as of 115 PM Wednesday...the thinking regarding the medium range 
remains consistent with a trough continuing along the eastern 
Seaboard through the middle of next week. At the surface...a frontal 
boundary is expected to drop southward and approach the forecast area during 
the day on sun...becoming quasi-stationary thereafter and remaining 
in the area through middle week. Therefore...will continue to carry 
solid chance probability of precipitation across the region through Wednesday...tapering off a little 
bit towards the end of the period as high pressure tries to build in 
from the north and push the old boundary further south. As far as 
temperatures go...warmest day will be sun with temperatures a few degrees above 
normal...then returning to values close to climatology for early and middle 
week. 


&& 


Aviation /02z Thursday through Monday/... 
it remains debatable whether convective line will be contain 
enough covering for a real thunderstorm threat at kclt...so will continue 
to mention just thunderstorms in the vicinity until about 02 UTC. Otherwise...VFR level 
clouds and light winds will be seen across the rest of the forecast area 
tonight. Will continue to limit any late night visibility restriction 
to just kavl for now. VFR conditions and winds less than 10 kts are 
expected all day on Thursday. 


Outlook...high pressure will remain over the area through 
Friday...providing generally VFR conditions. Scattered mainly 
afternoon and evening thunderstorms can be expected Saturday through 
Sunday. Some MVFR ceilings and visibility may occur in 
thunderstorms...with MVFR visibility at night in fog where rain 
falls. Another front will be in the area on Monday...which will 
support more thunderstorms and associated restrictions. 


&& 


Gsp watches/warnings/advisories... 
Georgia...none. 
NC...none. 
SC...none. 


&& 


$$ 
Synopsis...McAvoy 
near term...Ark/csh 
short term...McAvoy 
long term...bsh 
aviation...csh