Weather

463 
fxus62 kgsp 211857 
afdgsp 


Area forecast discussion 
National Weather Service Greenville-Spartanburg SC 
257 PM EDT Thursday Aug 21 2008 


Synopsis... 
high pressure will continue from New England...southward across the 
western Carolinas and northeast Georgia through Friday...gradually 
moving off the Atlantic coast this weekend. Meanwhile tropical 
cyclone Fay is expected to move slowly westward across northern 
Florida to southern Alabama this weekend. A weak cold front will 
approach the mountains on Monday...and may finally lift the remnants 
of Fay toward our region in the early to middle part of next week. 


&& 


Near term /through Friday/... 
despite easterly flow from the surface-700 mb...ridging and warm temperatures 
aloft...along with low surface dewpoints have effectively capped the 
atmosphere with just scattered-broken cumulus and cirrus shield from Fay lingering 
into the evening hours. Continued easterly flow should allow 
for redevelopment of stratcu overnight across much of the County warning forecast area 
and some showers could also develop...forced by the upglide 
and upslope flow. The deeper moisture north of the westward 
moving Fay is expected to edge closer to the region perhaps 
aiding in the continued isolated shower threat into Friday. 
Lower low level thickness values will advect SW resulting in 
marginally less warm conditions Friday afternoon. 


&& 


Short term /Friday night through Sunday/... 
as of 245 PM Thursday...latest models in decent agreement regarding 
the westward movement of Fay along the Gulf Coast under the deep 
layer ridge over the middle-Atlantic region. GFS is now a little 
farther north with the deep layer moisture...bringing it to both 
sids of the upper Savannah River valley. The NAM keeps it along the 
river and west. With the upper ridge in place...middle levels remain 
warm with subsidence inversion. Therefore...precipitation chances remain 
meager at best through Sunday. Kept some slight chance pop mainly along 
the Savannah River. Models Show Low level moisture moving into the 
area with the deep easterly flow. This combined with the upslope 
flow could bring some isolated showers to the Blue Ridge. Expect 
late night/early morning clouds to redevelop then dissipate by 
afternoon each day. Temperatures should remain right around normal. 


&& 


Long term /Sunday night through Thursday/... 
as of 255 PM Thursday...the 00z European model (ecmwf) and 12z GFS are is pretty good 
agreement with the remnants of Fay...at least early on. The remnant 
low recurves into the southern Appalachians allowing strong southerly flow to 
develop and bring lots of deep moisture into the area. The GFS does 
move the low out of the area faster than the European model (ecmwf). Given that there 
is good agreement early on...bring probability of precipitation up through the middle of the 
week...then slowly decrease by the end of the period. Temperatures 
start out around normal...then lows warm and highs cool with clouds 
and rain developing. 


&& 


Aviation /19z Thursday through Tuesday/... 
scattered-broken VFR level cumulus and gusty east-northeast winds will be seen across the forecast area 
through the afternoon. VFR conditions expected to continue into the 
evening horus. Continued mixing into the night should limit visibility 
restrictions to just patchy MVFR...but confidence increasing that 
a period of MVFR ceilings will develop and last through middle-morning 
Friday. 


Outlook...shower activity will remain minimal Friday and through the 
weekend...with the primary concern being overnight and morning fog 
and/or low clouds. There is the possibility of increased precipitation 
covering on Monday. 


&& 


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


&& 


$$ 
Synopsis...tjb 
near term...csh 
short term...rwh 
long term...rwh 
aviation...csh