Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 200140

Area Forecast Discussion
National Weather Service Louisville KY
940 PM EDT Mon Jun 19 2017

.Forecast Update...
Issued at 939 PM EDT Sun Jun 18 2017

Just a few clouds can be seen on satellite images remaining across
the region this evening. A very minor shower or two popped up across
the Bluegrass region earlier this evening, but since then we have
been dry. Have been watching the showers across IL this evening. The
latest trend in the HRRR has been for this rain to dissipate as it
moves into southern IN. This seems a reasonable solution given the
drier air in place. Therefore, have kept the forecast dry for
overnight and just adjusted pops up a bit into the 10% range.
Otherwise, no major changes were made to the forecast this evening.


.Short Term...(This evening through Tuesday night)
Issued at 250 PM EDT Mon Jun 19 2017

A surface analysis this afternoon has the cold front now across
middle Tennessee and far eastern Kentucky. In its wake, westerly
winds have brought in drier air evident by recent RAP analysis
showing PWATs around 1 inch or less (compared to yesterday`s 2-2.2
inches) and dewpoints in the mid 50s to low 60s. Visible satellite
shows a scattered cumulus deck across much of the area, and
temperatures range from the upper 70s to low 80s.

A weak shortwave trough rotating through Indiana and Ohio has
sparked isolated to scattered showers/storms this afternoon. As this
activity pivots southeastward, a few may brush parts of southeast
Indiana and the far northern Bluegrass region. Have introduced just
a slight chance (10-15%) of a shower through about 6-8 pm.
Otherwise, the remainder of the area will see pleasant evening
temperatures and the cumulus field should dissipate toward sunset.

For tonight, the main concern is any fog potential. The combination
of light winds, clear skies, and wet ground may lead to patchy fog
in areas across south-central Kentucky and the Bluegrass. However,
sufficient mixing this afternoon may limit how much fog actually
forms, so have kept wording as patchy but there could be some
locally dense fog for Tuesday morning. Otherwise, plan on lows in
the low to mid 60s.

High pressure then builds into the region for Tuesday and Tuesday
night providing seasonable conditions and less humidity. Plan on
high temperatures in the low to mid 80s, and lows Tuesday night in
the 60s.

.Long Term...(Wednesday through Monday)
Issued at 255 PM EDT Mon Jun 19 2017

Upper pattern really de-amplifies on Wednesday, and afternoon temps
will recover above climo again after one more coolish morning.
Without much in the way of southerly flow, humidity will remain low
with dewpoints just around 60.

Low-level flow backs to southerly Wednesday night and Thursday,
allowing the dewpoint recovery to begin, and priming the atmosphere
for a potential remnant tropical plume late in the week. Could even
start to see precip into south-central Kentucky by late Thursday,
but this is not a high-confidence scenario.

POPs ramp up in earnest Thursday night as the remnant low lifts
through the Deep South, and will be maximized Friday into Fri night
as the wave opens up and gets picked up in the westerlies. Normally
would avoid likely POPs 4 days out, but even if the tropical plume
doesn`t pan out, there still remains the issue of a surface cold
front dropping in from the north. Will continue to roll with low-end
likely POP Fri and Fri night. Given this squeeze play, will need to
watch for a heavy rain threat in this time frame.

Temps Friday through the weekend will be modulated by clouds and
precip, so expect to be near or below climo by day and above by
night. Any tropical moisture should be sheared out on Saturday, but
a continued series of disturbances will support at least chance POPs
for most of the weekend, with cooler and drier air likely to follow
early next week.


.Aviation...(00Z TAF Issuance)
Issued at 712 PM EDT Mon Jun 19 2017

Mainly VFR conditions are expected through this TAF forecast period.
The diurnal cu will continue to diminish this evening and winds will
become light and variable. Some light fog may be possible at BWG in
the morning. For the remainder of the day, winds will generally be
out of the west tomorrow with diurnal cumulus clouds developing
again in the afternoon.




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