Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 250509

Area Forecast Discussion
National Weather Service Louisville KY
109 AM EDT THU AUG 25 2016

...Updated Aviation Discussion...

...Forecast Update...
Issued at 802 PM EDT Wed Aug 24 2016

Latest mesoanalysis shows higher CAPE pool remaining across east-
central IL into south-central IN where dewpoints are in the mid 70s.
This is where the better dynamics remain as well characterized by
effective shear of 25 to 35 kts. As daytime heating wanes and
convective inhibition increases, expecting a decrease in storm
threat across southern Indiana. A widely scattered shower or
thundershower remains possible but in general most folks will stay
dry. Latest runs of the hi-res models are in similar thinking.

Adjust forecast in the near term to reflect current conditions, and
adjusted precipiation chances to mainly southern Indiana and far
northern Kentucky. Otherwise, the forecast is on track.

.SHORT TERM (Now through Thursday Night)...
Issued at 231 PM EDT Wed Aug 24 2016

Mesoanalysis shows a 5H speed max crossing central Illinois and a
very weak surface trof reaching from northern Illinois to central
Kentucky. The atmosphere has been diurnally destabilizing and a look
out the window shows some moderate cu developing. While there is
some weak capping showing up on AMDAR soundings and the radars over
Missouri and southern Illinois are very quiet as of this writing,
there may be enough forcing to spark scattered storms late this
afternoon into early this evening. The best chances will be over
southern Indiana. Any storms will then weaken when they move into
north central Kentucky as the sun sets and the storms run into
increasing ridging aloft. There is the potential for some strong
wind gusts out of the most robust cells, primarily north of the Ohio

Thursday morning a weakening cold front will reach from the Great
Lakes to the Texas Panhandle, and will drift down to the Ohio River
by evening. Mid levels will be very warm and the moisture supply
will be meager, so not much convection is expected from this
feature. Will keep PoPs very low. The best chance for storms will be
over southern Indiana in the late afternoon.

Tonight and tomorrow night will be stuffy with lows in the 70s.
Temperatures will surpass 90 Thursday afternoon with heat index
readings peaking around 100 degrees, especially along and west of
Interstate 65.

.LONG TERM (Friday through Wednesday)...
Issued at 237 PM EDT Wed Aug 24 2016

The story hasn`t changed much in the long term. A large upper ridge
will be present over the southeast United States with convection
firing around its periphery. With this pattern thunderstorms are
usually mostly diurnal, meaning the best chances for storms will be
in the heat of the afternoon with diminishing coverage in the
evening each day.

It will be a hot, hazy, humid period with highs in the lower 90s and
lows in the lower 70s at least through the weekend...maybe a couple
degrees cooler early next week as the ridge begins to weaken and
shift eastward.


.AVIATION (06Z TAF Update)...
Issued at 1250 AM EDT Thu Aug 25 2016

Expect a quiet night across Kentucky, with the only fog concerns
coming at BWG where SSW winds will be the lightest. Still carrying 3
or 4 kt there, so it`s a low-confidence MVFR visibility forecast. A
bit more wind at SDF and LEX so should remain unrestricted. Look for
diurnal cu beginning late morning, with winds increasing to a solid
10 kt. Not expecting enough coverage for a ceiling, and will not
include any convection as the better focus remains well to the
north, but can`t rule out a stray afternoon pop-up. Winds diminish
and cu will dissipate after sunset.


.LMK Watches/Warnings/Advisories...


Short Term.....13
Long Term......13
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