Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 240120

Area Forecast Discussion
National Weather Service Louisville KY
920 PM EDT Sat Sep 23 2017

.Forecast Update...
Issued at 920 PM EDT Sat Sep 23 2017

Mostly clear skies were noted across the region this evening and is
expected to continue into the overnight period.  With clear skies
and light winds, probably will see a little bit of river and valley
fog in the morning.  Some locally dense fog will be possible in the
typical fog prone areas.   Current forecast has a good handle on
this.  Did a complete weather element refresh of all short term
elements just to bring in line with current observations.  Full
suite of text and digital data has been produced and should be
available shortly.


.Short Term...(This evening through Sunday night)
Issued at 234 PM EDT Sat Sep 23 2017

Current surface analysis reveals broad 1023mb high over Lake Erie. A
weak surface boundary extends from northern Ohio into central
Kentucky, with slightly drier air east of the boundary under
northeasterly winds. Visible satellite reveals a cu-field near the
Tennessee border, and although some mid level instability exists,
capping near the surface is strong and will prevent any storms from
firing off today.

Quiet weather expected for most of the short term period. Mostly
clear skies and light winds will allow fog to form in river valleys
and fog-prone areas late tonight into tomorrow morning, though
coverage should be more limited tonight as slightly drier air will
be in place compared to previous nights. Upper level ridging will
gradually shift eastward tomorrow, and flow aloft will veer to the
southeast as a weak upper level low over the gulf coast region
begins to influence the region. A few models develop isolated
convection tomorrow afternoon in southwestern portions of the CWA
near Bowling Green, though a quick look at model soundings reveals a
decent cap in place. The NAM is the most aggressive of models and
completely erodes the cap. Without much of a lifting mechanism in
place, convective coverage should be very limited, and will keep
PoPs isolated at best in the forecast.

Any convection that does develop Sunday should dissipate by early
Sunday evening. Expect another mild night with overnight lows in the

.Long Term...(Monday through Saturday)
Issued at 238 PM EDT Sat Sep 23 2017

Little change to previous long term discussion. The hot and dry
weather will continue across our region through mid-week before a
strong cold front moves into the area. Moisture looks to be pretty
limited with this front so will keep forecast dry. Cooler, more fall-
like temperatures are expected Thursday and beyond as a strong
Canadian high pressure builds in.


.Aviation...(00Z TAF Issuance)
Issued at 652 PM EDT Sat Sep 23 2017

High pressure at the surface and aloft will continue to provide
clear and calm weather for the upcoming TAF period.  Another round
of locally dense fog is possible at KBWG and KHNB late tonight. Some
light fog may impact KLEX as well.   Winds tonight will be light and
variable.  The outlook for Sunday is for VFR cigs/vsbys with light
southeasterly winds.




Short Term...DM
Long Term....DM
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