Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 261046

Area Forecast Discussion
National Weather Service Louisville KY
646 AM EDT FRI AUG 26 2016

...Updated Aviation Discussion...

.SHORT TERM (Now through Saturday)...
Issued at 255 AM EDT Fri Aug 26 2016

Hot and humid conditions will persist into the weekend as upper-
level ridging centered over the Virginias and Carolinas remains in
control. The low-level jet over the Mississippi Valley has struggled
to produce any nocturnal convection, and today`s precip forecast
will hinge on how far westward the influence of ridging can win out.

Surface pattern is quite sloppy, making it difficult to identify any
boundaries to focus convection. Precipitable water values will
remain well above climo, but with the moisture concentrated in the
boundary layer, and convective temps in the lower 90s, believe
afternoon convection will remain isolated at best. Have limited POPs
today mainly to southern Indiana and west of I-65 in Kentucky.

Tonight into Saturday we`ll be closer to the periphery of the upper
ridge, so we could see nocturnal convection creep into west-central
Kentucky and southern Indiana around daybreak Saturday. If this
comes to pass, we could see a few boundaries to give an additional
kick to Saturday afternoon convection that would otherwise struggle.

Outside of any convection, very warm and muggy conditions will
continue, with temps several degrees above climo and afternoon heat
indices around 100.

.LONG TERM (Saturday Night through Thursday)...
Issued at 255 AM EDT Fri Aug 26 2016

Strong upper-level ridge will remain parked along the mid-Atlantic
coast for the latter half of the weekend, and then gradually break
down through the work week. For at least Sunday, will continue the
theme of 20-30 POPs focused on afternoon peak heating, and west of
I-65. POPs will be lowest across the Bluegrass region where ridging
aloft is the strongest.

Mon-Tue will be a transition as the ridging drops a bit to the
south, but still cannot push a surface boundary into the Ohio
Valley. Less capping will mean a bit more convective coverage, but
will still keep it in the chance category. Temps will still be able
to touch 90 each afternoon, with heat indices pushing 100.

Around mid-week a northern stream low digs into eastern Canada and
some faster NW flow aloft will start to impinge on the area. Could
see a slight break in heat and humidity, but we`ll still be at or
above climo. Forecast confidence is limited depending on the
eventual development and track of 99L, which is currently over the
SE Bahamas.


.AVIATION (12Z TAF Update)...
Issued at 645 am EDT Fri Aug 26 2016

Latest IR satellite imagery shows cirrus clouds across western KY
spilling into central KY and the TAF sites at this time. Fog has
been hit and miss, with some non-TAF sites reporting IFR to MVFR
vsbys, but little or none at the 3 TAF sites. Still think BWG and
LEX, especially BWG, could drop to MVFR early this morning before
quickly improving to VFR around mid morning. Otherwise, expect
scattered cumulus clouds around 4 kt later today as light surface
winds (3-6 kts) become E to NE. The terminal with a chance of storms
late this afternoon would be BWG, although with only isolated cells
expected, will not carry mention in their TAF at this time.


.LMK Watches/Warnings/Advisories...


Short Term........RAS
Long Term.........RAS
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