057 
fxus63 kpah 212059 
afdpah 


Area forecast discussion 
National Weather Service Paducah Kentucky 
250 PM CST Sat Nov 21 2009 


Discussion... 
in the shorter term /tonight through Sunday night/ leaned 
closer to the GFS/European model (ecmwf) deterministic/ensemble solution for 
clouds/winds/pop/weather...adjusting slightly southeastward to 
compensate for minor height/mass field variance from observed 12z 
Saturday observations. 


Introduced a small chance for showers across the southern pennyrile 
region from late Sunday afternoon through the overnight hours to 
Monday morning. Anticipate the main precipitation will be associated 
with lift in the deformation zone northwest of the opening upper 
low/wave moving from the lower Mississippi Valley into the middle 
Tennessee and Ohio valleys by 12z Monday. 


Should be a short break between systems Monday as weak high pressure 
moves in. However...next middle level short wave and associated surface cold 
front will be quick to move into the region Tuesday/Tuesday evening. This 
system is much stronger than the one this weekend...and should have 
a good deal of moisture to tap as it heads east. Will bump rain chances 
up some with this package...but will hold off on likely probability of precipitation at this 
point due mainly to timing issues between the deterministic 
GFS/ECMWF. Really believe many areas will get wet either Tuesday of Tuesday 
evening...but amounts should not be impressive. 


This initial front will bring drier and cooler conditions in for 
Wednesday...but another stronger front associated with colder air from 
Canada will likely sweep through just in time for Thanksgiving. 
Though this front looks to be somewhat moisture starved...clouds and 
deep cyclonic middle level flow behind the front may hold maximum temperatures in 
the lower and middle 40s for the Holiday. However...a slow warming 
trend should get underway toward the weekend...with dry conditions 
expected. 


&& 


Aviation... 
although it is not climatologically favorable...added a periodic 
mention of MVFR fog to kcgi in the 09-13z Sunday time frame to 
account for slight variability wind wind flow near the Diversion 
Channel next to the observation site. Otherwise...the remaining taf 
locations were kept in VFR category throughout the forecast 
period...with only scattered to broken coverage of cirrus spreading 
in from the west with time. 


&& 


Pah watches/warnings/advisories... 
Kentucky...none. 
MO...none. 
Illinois...none. 
In...none. 
&& 


$$ 


Smith/meffert