942 
fxus63 klmk 191736 
afdlmk 


Area forecast discussion 
National Weather Service Louisville Kentucky 
136 PM EDT Friday Mar 19 2010 


..updated aviation discussion... 


Short term (today and tonight)... 


A high pressure ridge currently extends from the Gulf states into 
the lower Ohio Valley. Very dry air in place this morning will lead 
to quickly dropping temperatures...with morning lows expected to be in the 
middle 30s across the southern Bluegrass to the middle 40s in urban areas. 


Other than increasing cirrus clouds from the west ahead of the next 
system...skies will be mostly sunny today. With the high pressure 
sliding east...winds will back around to the southwest today with a 
few gusts around 15 miles per hour or so. A gorgeous day indeed with afternoon 
highs expected to reach the upper 60s to low 70s! 


Friday night...we should see warmer lows as the thermal ridge will 
be over our far western County Warning Area. And with even more cloud cover increasing 
from the west...think low temperatures tonight will range in the upper 40s 
over west-central Kentucky to around 40 over the Bluegrass. 


Long term (saturday - thursday)... 


The broad area of high pressure that is bringing US the beautiful 
weather at the end of this week will be moving off to the east by 
Saturday morning. Meanwhile a deep upper level trough will set up 
across the central United States. This trough will deepen through Saturday 
night and become a closed low as it swings across the Mississippi 
Valley and then northeastward across Kentucky. 


The models continue to slightly slow the onset of precipitation with 
this system. Southern Indiana looks like the most likely place to 
see some showers on Saturday evening as a cold front slowly sags 
into this region and becomes stalled out ahead of the approaching 
surface low from the south. Rain chances will increase areawide 
through the day on Sunday with the heaviest and most widespread 
shower activity looking to be Sunday afternoon into the evening as 
an occluded front passes through central Kentucky. Though little 
surface instability is present with this system some marginal 
elevated instability can be seen on area soundings. Therefore will 
leave in the slight chance for thunderstorms on Saturday night and 
Sunday. Showers will continue through Monday as moisture wraps 
around the backside of the surface low. These should taper off 
Monday night with most of the precipitation out of the area by Tuesday 
morning. 


Saturday will see one more day of temperatures in the upper 60s to 
around 70. With clouds and precipitation temperatures will drop on Sunday 
back into the upper 50s. As the upper level low moves across 
Kentucky on Monday it will bring with it a pocket of much colder air 
with highs on Monday struggling to reach into the upper 40s. This 
will make for a very chilly and damp day. 


The low pressure system will depart quickly on Tuesday with ridging 
taking its place. This will allow for a warm up into midweek next 
week with dry conditions through Wednesday night. 


&& 


Aviation (18z taf issuance)... 


VFR through the period. 


Upper level trough across the central rockies will reach the southern/Central 
Plains during the period. Associated cold front...from northern Illinois to central MO 
at this time...will extend from southern in to southern Illinois to southeast MO by Sat afternoon with 
clouds...but no precipitation preceding it. Light SW/S winds will precede 
front as well. 


&& 


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


$$ 


Short term........al 
long term.........Ees 
aviation..........dk/11