Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 100527
Area Forecast Discussion
National Weather Service Louisville KY
127 AM EDT SAT OCT 10 2015
...Updated Aviation Discussion...
Issued at 932 PM EDT Fri Oct 9 2015
Rain has moved out of southern Indiana and north central Kentucky
this evening. Light to moderate rain will continue across south
central Kentucky for the next few hours but should move out well
before daybreak. Did another forecast update to remove the pops
completely from the north. Also tapered them off earlier in the
south. The forecast update is already out.
Issued at 620 PM EDT Fri Oct 9 2015
With drier air filtering into the northern portion of the forecast
area, rain has begun to dry up. Did a quick update to the pops over
the next few hours to lower them and dry things out more quickly
across southern IN and north central KY. Also tweaked the hourly
temp grids to bring them in line with current observations and
.SHORT TERM (Now through Sunday)...
Issued at 315 PM EDT Fri Oct 9 2015
A cold front was located over south central KY as of 300pm and will
continue to move SE into TN this evening. A cluster of strong
storms will continue over the next hour in the Cumberland Lake
region just ahead of this front. These strong storms may contain
strong winds and pea size hail. They should clear the area within
the next few hours leaving showers and maybe an isld embedded t-
storm in their wake.
Showers and low clouds will linger over the area for much of the
evening hours. Some of the latest models do indicate the upper
trough associated with this system will sharpen causing showery
activity to linger over south central KY through the early morning
hours Sat. Low clouds will start to clear over southern Indiana
near sunrise Sat morning. Low temps will hold in the upper 40s to
lower 50s overnight due to the clouds and lingering showers.
For Saturday, thick cloud cover will gradually clear from N to S
over the region during the morning hours with most places only
partly cloudy by Sat afternoon. The post-frontal airmass will
result in high temps ranging through the 60s to around 70.
For Saturday night, skies will become clear with sfc high pressure
and upper level ridging aloft. This will allow for optimal cooling
conditions dropping lows into the 40s.
.LONG TERM (Sunday night through Friday)...
Issued at 306 PM EDT Fri Oct 9 2015
The long term will begin with the region under the influence of a
ridge aloft and high pressure at the surface. Highs Sunday will top
out in the lower to mid 70s. Lows Monday morning will be quite a bit
warmer than Sunday morning thanks to continued southerly winds. They
will be in the upper 40s to lower 50s.
For Monday a shortwave trough and cold front will swing through the
lower Ohio Valley. The front should begin to move into southern IN
during the afternoon and push through the rest of the region through
the evening. Scattered showers will accompany this frontal passage
Monday afternoon and evening. Temperatures will rise into the mid to
upper 70s ahead of the front. Behind it cooler air will filter in
with highs topping out in the 60s Tuesday.
Northwesterly flow aloft will set up and remain in place through the
remainder of the forecast period. A couple of weak waves will move
through this flow, but for now they look to mostly stay to the north
of the forecast area. Thus will go with a dry forecast for Tuesday
through Friday. Temperatures will warm back into the 70s Wednesday
and Thursday with lows in the upper 40s to lower 50s. A dry front
then moves through on Thursday night with highs in the 60s once
.AVIATION (00Z TAF Update)...
Issued at 126 AM EDT Sat Oct 10 2015
The main issue with this TAF package will be ceilings. So far over
the last few hours ceilings have been VFR, and current obs and
satellite trends upstream show widespread low-end VFR ceilings.
Model guidance has backed off on low ceiling probabilities as well.
Will keep the northern TAF sites, which are deeper into the drier
air, VFR for the morning hours. Will still include some MVFR ceiling
at BWG, though, where there is more low level moisture.
Ceiling questions will continue into the daylight hours as moisture
gets trapped beneath an inversion, and current satellite pictures
show a large cloud field upstream over Missouri and Illinois.
Ceilings within that area of clouds are right around 3 thousand
feet, and models are progging that ceiling height over central
Kentucky today as well. Have decided to go on the pessimistic side
at BWG, hanging on to a low ceiling for much of the day and pegging
it right at 3,000 feet. Drier air in place at SDF and LEX will keep
the clouds scattered there, though transient ceilings right around
the VFR/MVFR border will certainly be possible this morning and
possibly even into early afternoon.
NNE winds around 5 to 10 knots, plus widespread clouds, should help
restrict fog to just the most sheltered locations this morning.
Tonight we will have clear skies and almost no wind, leading to the
question of fog. Right now dew point depressions are forecast to be
large enough that we can keep the SDF TAF VFR for now, but it will
be something to watch in later packages, especially at BWG.