810 
fxus62 kgsp 181845 
afdgsp 


Area forecast discussion 
National Weather Service Greenville-Spartanburg SC 
245 PM EDT Thursday Mar 18 2010 


Synopsis... 
weak but warmer high pressure will continue over our region through 
Saturday before moving off the Carolina coast. A cold front is 
expected to cross the western Carolinas and northeast Georgia from 
the west late Sunday with an upper level low passing on Monday. 
High pressure will again be the main influence from Monday through 
Thursday...until the next front arrives late in the week. 


&& 


Near term /through Friday/... 
as of 200 PM...a stacked...filling low will continue to spin in vicinity of 
the Carolina coast this evening...and begin to drift eastward 
tonight. Associated middle and upper level cloudiness will gradually 
decrease in coverage overnight. Also...as a surface low continues to 
move further offshore of the Outer Banks...high pressure builds in 
from the lower MS valley...resulting in a seasonably cool...tranquil 
night. Min temperatures will range from the 30s mountains to lower 40s Piedmont. 


Friday...a beautiful day on tap for the forecast area as high 
pressure continues to build in from the west. Under sunny 
skies...temperatures will be in the 60s mountains and lower to middle 70s Piedmont 
with light winds. 


&& 


Short term /Friday night through Sunday night/... 
as of 240 PM Thursday...fair and mild weather will continue on 
Saturday. High clouds will begin to increase...especially in the 
afternoon...but highs should still be a few degrees above Friday/S 
readings. 


The upper low that approaches the region on Sunday is fairly 
compact. It/S a strong feature...just not very broad. This limits 
the extent of the moisture transport out of the Gulf. Dry air will 
also work around the low from the southwest later in the day on 
Sunday. While there will still be a good frontal band out ahead of 
the low...these limiting factors will hold down on the amount of 
precipitation that falls across the region. Most places will certainly 
measure with this event...but the only place that looks to even 
approach an inch of rain will be over the southern NC mountains where several 
hours of upslope flow will enhance rainfall amounts. 


The frontal band will push slowly to the east of the region Sunday 
night. I/ve slowed the timing down about 6 hours from the previous 
forecast...which keeps likely probability of precipitation over most of the forecast area through 
midnight. Temperatures will cool aloft as the upper low approaches...and 
the higher mountain elevations should see some snow after midnight. The 
upper low looks...attm...to lift a little too far to the north for 
the best dynamics to affect the region...but some snow accumulations 
above 3500 feet is certainly possible. 


&& 


Long term /Monday through Thursday/... 
as of 240 PM Thursday...as the upper low passes from west to east 
across the North Carolina mountains or at least nearby...thickness 
values will fall with northwest flow moisture lingering especially along 
the Tennessee border areas on Monday. The upper low will slowly 
pass to the east of the forecast area by Monday evening...although 
the European model (ecmwf) still keeps it back over our area but this model has been 
consistently slower than the other models in the progress of this 
system. The European model (ecmwf) also takes the low farther south than the other 
models which is discounted. Not expecting much northwest flow snow...just 
mainly in the highest elevations. Heights begin to rise Tuesday and 
weak high pressure will prevail through middle week. 


The next system will reach our region on Thursday with showers 
moving into the area from the west. Keeping slight chance for 
eastern zones through Thursday night as the front makes very gradual 
progress. At this point...wind shear is minimal and cape is almost 
non-existent so leaving out any mention of thunder. There are model 
differences as the GFS has a weaker low centered over the Arkansas/miss 
border 18z Thursday and the European model (ecmwf) has a more dynamic system crossing 
North Texas at that time. Temperatures a few degrees above normal 
ahead of the system. 


&& 


Aviation /19z Thursday through Tuesday/... 
kclt and elsewhere...widespread middle and high clouds will remain over 
the western Carolinas through this afternoon. Low pressure over the 
western Atlantic will track east this evening. As the low 
departs...cloud cover over the region will begin to thin from west 
to east. North to northeast winds will remain light and may be 
variable across the foothills and Piedmont...with speeds ranging 
from 5-9 kts. After sunset...sky cover will become gradually clear 
with winds 3-5 kts or less. Friday through 18z...expect generally sky clear 
with light wind. 


Outlook...VFR is expected through Saturday. A cold front may bring 
restrictions with a line of showers and thunderstorms Sunday into 
Sunday night. Lingering rain/snow showers in the mountains and gusty 
southwesterly/westerly winds over the Piedmont expected on Monday. 


&& 


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


&& 


$$ 
Synopsis...deo 
near term...Arkansas 
short term...McAvoy 
long term...deo 
aviation...Arkansas