327 
fxus63 kjkl 131417 
afdjkl 


Area forecast discussion 
National Weather Service Jackson Kentucky 
1017 am EDT Monday Oct 13 2008 


Short term.../the rest of today/...updated 
no updates to the zones forecasts will be issued. Just made some 
minor tweaks to the dewpoints for this afternoon. Raised the 
dewpoints some in the southwestern portion of the County Warning Area as some 
moister air out ahead of the next system will start working its way 
into the area. Will update the grids...pfm and afm. 


The previous short term forecast discussion follows... 


/today through Wednesday/ 


Expecting mainly dry weather with much above normal through the 
period. Surface high pressure was centered over the Middle Atlantic 
States. The 500 mb high was centered over Kentucky this morning. Some scattered 
to occasionally broken cirrus will move across the area 
today...however this should be thin enough to allow for mostly sunny 
wording in the forecast. Near record highs are expected again today. 
The record for jkl is 84 set in 1985...with 85 at loz set in 1969. 
Dry air in the lower levels should allow for relative humidity values dropping to or 
below 30 percent again today...and will continue to highlight this in 
the fire weather forecast. Winds just above the surface should be 
lighter tonight than the past couple of nights...and this should 
allow for a little more uniform radiational cooling. Will continue 
with a Ridge/Valley temperature split the next couple of nights. Near 
record highs will be possible again on Tuesday. Moisture will try to 
increase slightly in the western and northwestern portion of the County Warning Area 
as well on Tuesday....with few more clouds expected. By Wednesday a 
cold front will be slowly approaching from the northwest as the 500 mb 
high begins to shift south. Prefer the slightly slower timing of the 
NAM with this system considering the upper air pattern. Will keep a 
mention of slight chance probability of precipitation late in the day north of the mountain 
parkway. 


Long term.../Wednesday night through Sunday/ 


Long term looks very similar to previous runs and not much has 
changed. Only consequence of note is that all models have slowed 
the progression of precipitation into eastern Kentucky. Therefore...have slowed onset 
some with best chance now late Thursday into Thursday night. 


Dominant high pressure starts and ends this forecast with the cutoff low 
in the desert SW ejecting NE into southern Canada. This low will do little 
more than prime the air to our north and lay a weak stationary front 
across the southern Great Lakes. Then a secondary wave...now seen entering the 
northwest Continental U.S....will drop through the front and push it across the 
commonwealth. Due to a severe lack of available moisture...the best 
chance will only amount to 30 percent or less around midnight Thursday 
night. The front probably will not generate that much quantitative precipitation forecast. 


For the latter half of this extended forecast...the operational 
European model (ecmwf) and GFS are in much better agreement with the upper low diving 
southeast out of Canada. This becomes a much deeper trough overhead by 
Saturday morning...with amplified ridging over The Rockies out west. 
Have inserted a slight chance of showers over the northestern half of the County Warning Area 
on Friday because of this troughing. However this moves east quickly 
and high pressure will dominate again. However the weekend will still 
be chilly with saturday's highs in the middle 60s and sunday's highs 
rebounding a bit into the upper 60s. 


&& 


Aviation.../12z to 12z/ 


High pressure centered over the Middle Atlantic States will continue to 
bring VFR conditions and light south winds through the period...with 
a few cirrus expected. 


&& 


Jkl watches/warnings/advisories...none. 


&& 


$$ 


Short term...wjm/jj 
long term....dusty 
aviation...jj