961 
fxus63 klmk 070649 
afdlmk 


Area forecast discussion 
National Weather Service Louisville Kentucky 
248 am EDT Tuesday Oct 7 2008 


Short term (today and tonight)... 


Much needed rainfall will be likely from late this afternoon through 
the overnight hours as a deep trough and low pressure system 
approach the area today and tonight. Currently...upper level 
cloudiness is moving into the area in response to this system. The 
story for today remains much the same as the last few days. 
Conditions will remain dry through midday with an increasing chance 
for showers and thunderstorms by this afternoon. Increased probability of precipitation in 
the east between 18-00z as thunderstorm chances will increase in the 
late afternoon. Clouds will also be on the increase during this time 
with much of the area becoming cloudy by the afternoon hours. 
Therefore...lowered temperatures a bit and expect highs in the from 
the middle 70s to near 80 across the area. Winds may also be gusty 
today as the pressure gradient increases somewhat with high pressure 
to our east and low pressure moving in from the west. Winds 
increasing to 20 to 35 knots at 925 and 850 mb this afternoon will also 
aide in some stronger surface winds through evening. Do not expect 
any thunderstorms that develop to be severe today and heavy rain at 
times will be the main concern. 


The best chance for rainfall will be tonight as upper trough and 
surface low continue to move eastward and dig. Plenty of Gulf 
moisture will have been streaming northward during the day and many 
areas should see good rainfall rates...with deep saturated warm 
cloud layers...despite the relatively quick movement of the system. 
Increased probability of precipitation and quantitative precipitation forecast amounts overnight to reflect confidence in 
forecast and due to the above mentioned facts as well as model 
guidance being in very good agreement. As mentioned before...periods 
of moderate rainfall are expected and some locations may see up to 
three quarters of an inch of precipitation by Wednesday morning. 
Overnight lows will remain fairly warm due to overcast skies. Expect 
lows to hover around the 60 degree mark in most locations. 


Long term (wednesday through Columbus day)... 


A sharp upper trough lined up along the length of the Mississippi 
River at the beginning of the period will move east to The Spine of 
the Appalachians by Thursday morning while de-amplifying. At the 
surface a weak cold front will pass through the region from west to 
east Wednesday and Wednesday night...then lose much of its 
identity to our east on Thursday. 


By far the best chance of rain in the long term will be during the 
day on Wednesday. The Gulf of Mexico will be wide open and high 
pressure off the Virginia coast combined with low pressure over 
Michigan will draw that moisture northward into the frontal zone 
stretched across our region. Looks like good shower 
coverage...especially Wednesday morning. Over the course of the day 
on Wednesday general rainfall amounts will likely be in the 1/4 to 
1/2 inch range...similar to the system that moved through here on 
the 29th and 30th of September. A few thunderstorms could develop 
but dynamics with the system are fairly weak. 


Later in the week and into the weekend a strong upper trough will 
dig into the American west...building a ridge over the east in 
response. As a result it looks like we will return to dry weather 
conditions. Temperatures will moderate under the ridge with 
afternoon highs by Friday and Saturday 5 to 10 degrees warmer than 
normal. 


Thanks to iln...jkl...and ind for coordinate. 


&& 


Aviation (06z tafs)... 


VFR conditions are expected through about 18z today. 
Currently...high and middle level clouds will persist over the area 
through the morning hours...spreading eastward through midday. 
Ceilings will become broken-overcast by 15-18z. Showers and thunderstorms 
will develop across the east and may affect bwg and sdf by 18z as a 
surface low and frontal boundary approach the area. These showers and 
thunderstorms will spread eastward through the evening and overnight 
hours and eventually affect all taf sites tonight. Ceilings should 
remain VFR but visibilities will be reduced between IFR and MVFR at 
times as rainfall may occasionally be heavy. Besides low 
visibilities at times...winds may gust briefly to 25 kts near any 
thunderstorms that develop. 


&& 
Weather.Gov/Louisville 


Lmk watches/warnings/advisories... 
Kentucky...none. 
In...none. 
&& 


$$ 


Short term...ls 
long term....13 
aviation.....Ls