096 
fxus62 kgsp 131450 
afdgsp 


Area forecast discussion 
National Weather Service Greenville-Spartanburg SC 
1050 am EDT Monday Oct 13 2008 


Synopsis... 
warm and dry high pressure will settle over the southeast through 
the middle part of the week. A weak cold front is expected to cross 
the Carolinas and northeast Georgia late Thursday or Friday. 


&& 


Near term /through tonight/... 
upslope stratocu over extreme NE Georgia should eventually mix out around 
middle day. Few to scattered diurnal cumulus may develop this afternoon over the 
mountains and foothills. However...the cumulus should remain fairly shallow 
under a strong subsidence inversion around 850 mb. Conditions should 
remain sunny to mostly sunny with weak east-northeast surface wind. Mild afternoon 
low level thicknesses...strong insolation...weak mixing will likely 
result in maxes very close to the current forecast. I will update 
grids with observations and make slight adjustments to hourly rates. 


As ridging lingers...good radiational 
cooling conditions expected tonight with a clear sky and light wind. 
Only made isolated downward tweaks to the inherited min temperature forecast of 
values right around middle-October normals. Would not be surprised to 
see areas of Mountain Valley/Lake fog develop overnight given expected 
clear...calm and cool autumn conditions in combination with still 
mild water temperatures. 


&& 


Short term /Tuesday through Wednesday night/... 
the upper anticyclone will settle across the southeast through the 
middle part of the week allowing dry high pressure to dominate our 
weather through Wednesday night. The real story for the short term 
will be the high temperatures. All the guidance came in warmer for both 
Tuesday and Wednesday so maximum temperatures were nudged up nearly a category 
across the board...which brings US even closer to record highs on 
both days at all locations. A weak downslope east of the mountains 
supports this possibility. Low temperatures were kept more in line with the 
mav guidance. Although the dry air mass will support a large diurnal 
range...the met guidance looks too cool over the mountains where it seems 
doubtful that upper 30s would happen in between two record warm 
afternoons. 


&& 


Long term /Thursday through Sunday/... 
as of 245 am Monday...the latest guidance through the medium range 
is in general agreement about keeping a cold front to the northwest 
on Thursday...which means at least one more seasonally warm day. 
Similar to the short range...the high temperature on Thursday was nudged up 
a degree or two with the guidance trend. 


Beyond that...the guidance differs on how to handle the passage of 
this first front and the dynamic upper system forecast to dig down 
over the east on Saturday. The GFS seems to slip the front through 
Thursday night or early Friday while the European model (ecmwf) holds the front up 
until a strong shortwave drops down with the deepening upper trough. 
Consequently...that model develops a good bit of precipitation on Friday. 
Have decided to go along with the latest mosguide which shows a 
chance of precipitation across the entire forecast area Friday...in 
deference to the latest European model (ecmwf). This ends up being a slight increase 
in pop across the region. 


The trend of the guidance is decidedly cooler for the weekend once 
the upper trough axis digs over the East Coast Saturday. Have cut a 
category off temperatures for each period after Friday night based on this 
new development. 


&& 


Aviation /15z Monday through Friday/... 
areas of VFR level stratocu ceilings across the southwestern half of the 
forecast area will diminish through mid-morning...otherwise the daytime hours will 
feature lots of dry air...just a few cirrus and diminishing wind as high 
pressure center builds toward the forecast area. With clear and calm conditions 
expected tonight...areas of valley fog are probable...and have 
introduced 3sm br at kavl and will leave any downward adjustment 
decision to later issuances if guidance remains consistent with 
forecasting visibilities dropping to LIFR. 


Outlook...some early morning fog will be possible...mainly 
at kavl the next few days...otherwise look for dry weather to 
continue into Thursday. Shower chances will increase somewhat 
Thursday night into Friday. 


&& 


Climate... 
high temperatures Tuesday and Wednesday will be well above normal 
for middle October. If current forecast highs verify...all three 
climate sites listed below will be within 3 degrees of records at 
least one of those two days. 


Here are the daily record high temperatures and the year in which 
they occurred. 


Tuesday 10/14 


Greenville-Spartanburg 86 1985 
Charlotte 87 1940 
Asheville 82 1928 


Wednesday 10/15 


Greenville-Spartanburg 86 1935 
Charlotte 88 1985 
Asheville 82 1950 


&& 


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


&& 


$$ 
Synopsis...PM 
near term...Ned/csh 
short term...PM 
long term...PM 
aviation...csh 
climate...akr