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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOUISVILLE KY
319 AM EDT Sat Apr 18 2015

.SHORT TERM (Now through Sunday)...
Issued at 250 AM EDT Sat Apr 18 2015

The first issue in the short term will be how much fog develops this 
morning. A few areas of fog have developed this morning, mainly across 
south central Kentucky, though much of it is light fog. Will 
continue to monitor conditions via obs and webcams for areas of 
dense fog. 

Any fog that develops will dissipate shortly after sunrise. The 
remainder of the day will be partly cloudy and warm for this time of 
year as we remain under the influence of ridging aloft. Mainly high 
clouds are expected across the region today, with a few Cu moving 
into south central Kentucky late this afternoon. Temperatures will 
top out some 10 degrees above normal this afternoon in the upper 70s 
to around 80.

Dry weather will not last, however, as a low pressure system moves 
out of the Mid Mississippi Valley tonight and across Indiana Sunday. 
Rain will be on the increase through the evening hours across south 
central Kentucky and spread into north central KY and southern IN 
after midnight. Precipitable water values will increase to around an 
inch and a half. Soundings show some elevated instability overnight 
as well, so isolated to scattered thunderstorms will accompany the 
showers with moderate to heavy rain at times.

For Sunday rain will be ongoing in the morning hours with the initial 
wave moving off to the northeast through the morning. Winds aloft 
will increase by the afternoon and sounding become unstable. A 
shortwave will approach from the west. This will spark more 
scattered showers and thunderstorms. Some of the storms in the 
afternoon could become strong with gusty winds. Additionally, 
rainfall amounts of a half an inch to an inch and a half will be 
possible through this period which could cause additional rises on 
area rivers and ponding of water in low lying areas.

.LONG TERM (Sunday night through Friday)...
Issued at 315 AM EDT Sat Apr 18 2015 

Models are in fairly good agreement with the pattern across the 
Midwest and Ohio Valley Sunday night, with a surface low over 
northern or central IN and another low forming over AR. Both of 
these lows are connected by a cool front. Moisture ahead of this 
front will continue the rain chances from Sunday into Sunday night. 
The actual front should push through Monday morning, but model QPF 
fields indicate some light returns behind it, as trough aloft 
continues over the region, so cannot rule out some light 
rain/drizzle during the day Monday. 

We're still looking at a dry Monday night and Tuesday, but then the 
GFS and to a lesser extent the Euro bring in some more light precip 
Tuesday night/Wednesday as another cool front approaches the region. 
In fact the GFS brings a series of these fronts through the end of 
the week, keeping rain chances in. The Euro and GEM are not quite as 
pessimistic, so will keep those chances fairly low for now. However, 
they do all show a more organized system getting together over the 
Central Plains on Friday, helping to strengthen a warm front 
somewhere in our vicinity. 

Temperatures will be around normal for this period, though any of 
the cloudier days have a better chance to go below normal for highs.

&&

.AVIATION (06Z TAF Update)...
Updated at 145 AM EDT Sat Apr 18 2015

Mainly VFR conditions are expected through this TAF period, with the 
exception of a few hours of light fog at BWG this morning. Skies 
have cleared for the most part with just some lingering high clouds 
over LEX. Winds will be light and variable to calm for the remainder 
of the night. Any MVFR fog that develops will quickly dissipate 
after sunrise. 

The remainder of the day will see winds in the 7-10 knot range out 
of the east. Mainly high clouds are expected through the day today. 
Lower clouds will increase tonight ahead of a system moving in from 
the southwest. Rain showers will move into BWG just after 0Z, but 
should hold off until after 06Z at SDF and LEX tonight.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&

$$

Short Term........EER
Long Term.........RJS
Aviation..........EER

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