Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 180719
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
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
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.