065 
fxus62 kgsp 051130 
afdgsp 


Area forecast discussion 
National Weather Service Greenville-Spartanburg SC 
730 am EDT Sat Jul 5 2008 


Synopsis... 
a weakening cold front will move toward the Carolinas through 
Sunday. A ridge of high pressure will build into the region early 
next week and persist until another cold front approaches by late 
week. 


&& 


Near term /through tonight/... 
for the very near term...expect isolated/widely scattered convective 
activity to continue through sunrise as left over instability is 
gradually used up. Expect to see more patchy fog in locations that 
received rain in the last 12 hours. As for today...our chance for 
more convective activity actually has quite a lot going for it. 
Upper divergence...the approach of a middle level short wave... 
relatively deep moisture...and low level convergence along lingering 
boundaries all should provide a favorable environment. After an 
early morning lull...convection should fire from west to east during 
the middle part of the day and carry on through the late evening. A 
few severe wind gust producing storms are not out of the question... 
but the potential is not quite as high as Friday because middle levels 
are not as dry and dcape should not be as high. The highest pop was 
put over the mountains/foothills as it is in the guidance...being that a 
weak surface boundary should drift in there from the west to provide 
a bit more focus. A chance pop was kept all night similar to what is 
transpiring now. Temperatures were nudged toward the mav guidance. 


&& 


Short term /Sunday through Monday night/... 
as of 240 am Saturday...the GFS and NAM are in better agreement 
regarding the position/intensity of the upper trough over the tenn/ 
Ohio valleys. However...discrepancies remain regarding the evolution 
of this feature. The GFS continues to feature a more progressive 
upper pattern...sweeping the trough east of the County warning forecast area by Monday 
afternoon. Meanwhile...the NAM maintains the trough in the vicinity 
of the Appalachians through Tuesday morning. Considering that the GFS 
has been the most consistent model with this feature...and that the 
NAM appears to be gradually trending toward the GFS with each 
run...we will generally side with the GFS. A continued moist/ 
unstable airmass along with upper support from the trough will lead 
to good coverage of convection again on Sunday...particularly across 
the eastern zones...where moisture/instability should be maximized. 


The axis of deep moisture will begin to shove off to the east on 
Monday...but with the trough still in the area...scattered diurnal 
convection will develop once again. 


&& 


Long term /Tuesday through Friday/... 
as of 250 am Saturday...the sub-tropical ridge will build into the 
southeast early next week. Sufficient moisture will remain in place 
over Georgia and the Carolinas to warrant chances for diurnal 
convection through mid-week. The medium range models continue to 
depict a frontal boundary approaching from the northwest by the end 
of the period. However...this doesn/T figure to have a huge impact 
on sensible weather. Chances for mainly diurnal convection and temperatures 
near climatology will continue through day 7. 


&& 


Aviation /12z Saturday through Wednesday/... 
a favorable environment for deep convection coupled with relatively 
deep moisture means that showers and thunderstorms could develop 
really at just about any time and place today and tonight. All 
terminals will get a thunderstorms in the vicinity from midday Onward and we will handle the 
restrictions with amendments when the timing can be determined. 
Clouds will be VFR outside of showers. Flow should be some variation 
of south. The convection should continue well into the evening hours 
similar to Friday evening. Late tonight...an MVFR visibility is a 
good bet at any terminals that experienced a shower today...so it 
will be featured in all tafs. 


Outlook...moisture will continue to increase through Sunday with 
solid chance showers/thunderstorms through weekend...including ceiling/visibility 
restrictions. Diurnal convection can be expected through middle 
week...with lower ceiling/visibility in vicinity of showers/thunderstorms. 


&& 


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


&& 


$$ 
Synopsis...jdl 
near term...PM 
short term...jdl 
long term...jdl 
aviation...PM