197 
fxus61 krlx 240151 
afdrlx 


Area forecast discussion 
National Weather Service Charleston WV 
951 PM EDT Wednesday Jul 23 2008 


Synopsis... 
high pressure dominates Thursday and Friday. Another cold front 
moves across Saturday...which stalls just to our south Sunday and 
Monday. 


&& 


Near term /through Thursday/... 
drier air spilling into area as front now east and south of 
County Warning Area. Expecting mostly clear skies by 06z. Fog will be fairly 
light...development will be hindered by drier airmass advecting 
in...as well as a puff of wind just above the boundary layer ahead 
of advancing high. Leaned towards cooler side of MOS but still 
stayed a degree or two above mav numbers. 


Surface high noses in thereafter...with the center getting into the 
County Warning Area by 00z Friday. After fog burnoff...Thursday will be quite pleasant 
for a late July day...with comfortable dewpoints in the 50s. Only 
foresee scattered cumulus during the afternoon hours with meager moisture. 
Went closer to warmer mav for highs. 


&& 


Short term /Thursday night through Saturday night/... 
models agree on slow moving cool front dropping slowly across the 
area Saturday...as unusually strong upper trough over the 
northeastern U.S. Becomes established. Surface high pressure with 
much drier and seasonably warm air dominates Thursday and shifts 
east on Friday as the system approaches for Saturday. Moisture and 
instability rapidly increases later Friday and continues until the 
front passes later on Saturday or Saturday night. There are a number 
of upper impulses preceding this main weekend system...which models 
respond by putting out chances of showers anytime from later Friday 
afternoon until the front passes. Since models have a difficult time 
handling these minor impulses...will focus on the system supporting 
the cool front for timing of convection. This will place the high 
chance of convection mainly in the west Friday night and early 
Saturday...and in the east Saturday into Saturday night...before the 
front passes. One thing is certain...no heat waves. 


&& 


Long term /Sunday through Wednesday/... 
models agree the mean upper trough over the northeastern U.S. Will 
be maintained this period. While a series of short waves and 
reinforcing shots of cooler air will move across our region this 
period...timing and exact track of these systems this far out is 
difficult. Have chosen...along with HPC...to focus on the frontal 
boundary which meanders just south of our area this period. This 
keeps some chance probability of precipitation in the forecast nearly every day...especially 
over the south where waves of low pressure will ride along the 
front. Any short wave/reinforcing shot of cooler air traversing the 
upper trough will further enhance the prospects for convection 
across the area. One thing is continues almost certain...no heat 
waves or extended dry periods. Temperatures near normal. 


&& 


Aviation /02z Thursday through Monday/... 
front is moving east of area allowing for clearing skies. A lower 
dewpoint airmass will be moving in...plus there may still be some 
wind just above the surface through the night. This will 
complicate the fog forecast. Only confident of dense fog at 
ekn/48i/i16 and constructed grids/taf as such. Crw should still 
get to IFR. Only have MVFR visibilities in the rest of the area 
for now. Fog Burns off by 14z...with a pleasant late July VFR day 
on Thursday. 


Aviation outlook /after 00z Friday/... 
no significant weather expected. 


&& 


Rlx watches/warnings/advisories... 
WV...none. 
Ohio...none. 
Kentucky...none. 
Virginia...none. 


&& 


$$ 
Synopsis...jkf 
near term...jkf 
short term...jmv 
long term...jmv 
aviation...jkf