Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 271911
Area Forecast Discussion
National Weather Service Louisville KY
311 PM EDT TUE SEP 27 2016
.SHORT TERM (Now through Wednesday Night)...
Issued at 255 PM EDT Tue Sep 27 2016
A deep 500mb closed low centered over the Great Lakes region this
afternoon will sink south into the lower Ohio Valley through the
short term period. A couple of vorticity lobes rotating around this
upper low will bring some rain chances to the region through
A strong vortmax will approach and move through during the day
tomorrow. Showers will develop across Indiana on Wednesday morning.
They will become more numerous through the morning hours across
southern IN and move through central Kentucky through the afternoon
hours. Steeper lapse rates, especially across central KY in the
afternoon will lead to some instability. With freezing levels around
8-9 kft, a few rumbles of thunder are possible. Some very small hail
also cannot be ruled out tomorrow afternoon. The scattered line of
showers will move east of the area late tomorrow afternoon, but some
more showers could develop overnight, mainly across southern IN and
north central KY as another weaker disturbance moves through.
Lows tonight should be a bit warmer than last night in the lower to
mid 50s. Tomorrow`s highs are tricky as they will depend on rain
coverage and cloud cover. Lows tomorrow night will be back into the
upper 40s to around 50.
.LONG TERM (Thursday through Tuesday)...
Issued at 308 PM EDT Tue Sep 27 2016
Thursday - Saturday...
The upper low will stall out and meander around the lower Ohio
Valley through the beginning of the weekend. This will lead to cool
temperatures and rounds of showers and a few rumbles of thunder
through Saturday. Rain will not be continuous through this period as
the timing of showers will depend on the vortmaxes rotating around
the upper low. In general, precipitation chances have been
increased further to the south and west through this period as models
get a better handle on the position of the upper low and moisture
associated with it.
Thursday and Friday will be cool with highs topping out in the 60s
across the region. There will be a small diurnal spread with lows in
the 50s. We could start to see a bit of a warm up by Saturday as
the upper low begins to lift off to the northeast.
Sunday and Monday...
The upper low will continue to lift out through Sunday. As it does
we will see a return to a drier forecast along with moderating
temperatures. Highs look to climb back into the 70s with lows in the
.AVIATION (18Z TAF Update)...
Issued at 133 PM EDT Tue Sep 27 2016
Expect a VFR day and night with a steady WSW or W wind. A few gusts
between 15 and 20 mph can`t be ruled out, but not expecting it to
prevail enough to put mention at this time. A strong and expansive
upper low will swing down toward the TAF sites by Wednesday morning,
with Sct-Bkn mid level clouds increasing. Scattered shower chances
will also increase late Wednesday morning into the afternoon. Can`t
rule out some isolated thunder and gusty winds with any shower.