Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 270113
Area Forecast Discussion
National Weather Service Louisville KY
913 PM EDT MON SEP 26 2016
Issued at 910 PM EDT Mon Sep 26 2016
Have updated the forecast to include patchy advection fog overnight
near lakes and rivers, to account for much cooler air moving in over
the warm water that has seen little cool down for the past several
weeks. No other changes for now.
.SHORT TERM (Now through Tuesday Night)...
Issued at 300 PM EDT Mon Sep 26 2016
Rain showers continue to move east over portions of east central and
south central KY this afternoon. They should clear the area by
early this evening. An area of clouds behind the rain looks to
clear the area by late evening with most of the overnight hours
expected to be mostly clear. With clearing skies in the post-
frontal airmass, we should see a good drop in temps with lows in the
mid 40s to around 50 degrees.
Sfc high pressure and a broad upper trough will dominate the region
for Tues resulting in mostly sunny skies and very fall-like
temperatures. Highs will top out in the lower 70s Tues afternoon
with lows Tues night in the upper 40s/lower 50s.
.LONG TERM (Wednesday through Monday)...
Issued at 315 PM EDT Mon Sep 26 2016
Wednesday - Saturday...
An upper low will wobble down into the Ohio Valley from the upper
Midwest bringing cool and rainy conditions for the second half of
the week. Rain chances will be maximized each afternoon/early
evening with better instability in the region. Vorticity lobes
rotating around the upper low will help spark convection.
High temperatures will be on a downhill trend through Thu/Fri. With
the upper low wobbling very near or right over KY both days, expect
highs to be limited to the 60s both Thu/Fri...potentially colder.
Low temps should hold in the upper 40s/lower 50s each night
depending on cloud cover.
Sunday - Monday...
By early next week, models indicate the upper low will shift NNE out
of the region. With this shift, a warm up in temps can be expected
as well as dry conditions.
.AVIATION (00Z TAF Update)...
Issued at 725 PM EDT Mon Sep 26 2016
Clearing skies and bone dry air are making their way into the
terminals early this forecast period. By the time the TAFs go into
effect, the clearing line will already be past both SDF and BWG, and
will move though LEX in the first hour.
Following this clearing, clear skies and light northwest winds
should prevail for the remainder of the forecast period at SDF and
LEX. That being said, there IS a non-zero chance for advection fog
at BWG as much cooler air moves in. Given BWG`s proclivity for fog,
this cannot be discounted, especially given the rainfall of 0.30"
today and the forecast min temperature 8 degrees lower than the
current Td. The most recent guidance takes BWG down to LIFR vsby,
but will not go that low, as this is not a certainty. Needless to
say, however, this will be closely monitored overnight.