Area Forecast Discussion
Issued by NWS Louisville, KY
FXUS63 KLMK 250526
Area Forecast Discussion
National Weather Service Louisville KY
126 AM EDT MON JUL 25 2016
...Updated Aviation Discussion...
Issued at 830 PM EDT Sun Jul 24 2016
Did an update to remove the headline from the zones. Also, some of
the high res guidance tries to develop a line of scattered storms
oriented parallel to the Ohio River before daybreak. We will have
some elevated instability. In addition, we could see something drop
down from the cells currently over Illinois. QPF fields from these
models look overdone, but will give them some respect and throw in a
20 pop along and north of the Ohio after midnight.
.SHORT TERM (Now through Wednesday)...
Issued at 243 PM EDT Sun Jul 24 2016
Other than a stray pop-up shower this evening, tonight will be
another dry but warm and muggy night with lows in the lower and
A broad surface trof will come in from the northwest by Monday
afternoon and will get hung up somewhere between the Ohio and
Tennessee Valleys through Wednesday. This will help to focus and
increase shower/storm chances for the first half of the work week.
The eastern arm of the upper ridge that has been overhead for the
past couple of days will generally maintain itself through Tuesday
before gradually diminishing Tuesday night-Wednesday. 7H temps will
be correspondingly quite warm, but then decrease a degree or two for
Tuesday and Wednesday. So, we may have slightly better coverage of
storms, particularly in the afternoon, Tuesday and Wednesday versus
Monday, especially if that surface trof still has some identity and
is nearby Tue-Wed.
Thunderstorm development may get some assistance from upper level
divergence just south of the upper jet stream extending from the
Midwest to the upper Ohio Valley. However, mid- and low-level winds
will be very weak, with very weak shear as a result. Precipitable
water values will hover around 2 inches through the period
(especially Tuesday and Wednesday) so we could still get some gusty
winds associated with torrential downpours crashing to the ground in
the stronger storms.
Monday will be another warm one with afternoon heat index readings
peaking around 100, especially west of I-65. Air temperatures will
be a couple degrees cooler Tuesday and Wednesday with increased
cloud and shower coverage, but humidity will remain high enough to
keep outdoor conditions uncomfortable.
.LONG TERM (Wednesday Night through Monday)...
Issued at 256 PM EDT Sun Jul 24 2016
A pool of moisture oriented east/west across the region as well as
disturbances aloft crossing the Midwest, as we stay in more of a
trough pattern, will mean continued chances for thunderstorms to
close out the work week and into the next work week. High
temperatures should be seasonable, with highs in the mid to upper
80s, whereas lows may be a little above normal, thanks to that
.AVIATION (06Z TAF Update)...
Issued at 125 AM EDT Sun Jul 25 2016
VFR conditions are expected for much of the overnight at the TAF
sites. Probably will see a little bit of haze develop at KSDF
between 25/10-13Z. Cu field will redevelop after 25/15Z and a front
will continue to push down from the north. Convective allowing
models show scattered storms developing around 25/18Z and lasting
through about 26/00-01Z. So we will keep the PROB30 groups going in
the TAFs. Surface winds will be light and variable overnight with a
southwest flow expected this afternoon.