Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 201036

Area Forecast Discussion
National Weather Service Louisville KY
636 AM EDT Tue Jun 20 2017

...Updated Aviation Discussion...

.Short Term...(Today through Wednesday)
Issued at 310 AM EDT Tue Jun 20 2017

Morning satellite imagery and obs show mostly clear skies over
southern KY with a batch of mid-level clouds moving through southern
Indiana and northern Kentucky.  A few radar returns have been
showing up with these clouds.  Over the next few hours, this
activity will move east-southeast.  Have updated the forecast in the
near term with some slight chance PoPs to cover the isolated rain
showers moving through.  Temperatures this morning were in the lower
to middle 60s.  Temps are not expected to move too much in the near
term but should settle into the upper 50s to the lower 60s for lows
this morning.

As we move into later today, high pressure will gradually build into
the region from the northwest.  This should yield partly to mostly
sunny skies for the afternoon hours.  Highs will warm into the upper
70s to around 80 in the east, with lower 80s out across the I-65
corridor and points west.  Mostly clear skies are expected for
tonight with lows cooling into the lower 60s in most areas.  A few
of our cooler spots could touch the upper 50s again.

Dry and warmer weather remains on tap for Wednesday as the high
pressure center heads off to the east and we get more of a southerly
flow into the region.  Highs will range from 83-88 across our
eastern sections with highs of 85-90 from the I-65 corridor and
points west.

.Long Term...(Wednesday night through Monday)
Issued at 215 AM EDT Tue Jun 20 2017

Latest NHC forecast places a tropical storm just offshore of the
TX/LA border Wednesday evening. This position is in reasonable
agreement with both deterministic and ensemble model solutions. That
should mean for us relatively quiet weather to start, but with
temperatures starting off above normal. During the day Thursday, we
will surge tropical moisture being to surge northward, well ahead of
the tropical system by then potentially inland over Louisiana.
GFS/NAM/GEM all peg that moist airmass with precipitable waters
above 2 efficient rain producers are possible. If true,
this moisture would be near the record value for the date, according
to SPC sounding climatology for BNA/ILN. The last time the models
called for near record values this past Sunday, I was a little
skeptical, but the 12Z ILN sounding Sunday and the 00Z BNA sounding
Sunday evening did end up getting to record values. We didn`t get
much in the way of flooding, but do note that RFC`s flash flood
guidance values are coming down.

After that first wave, the moisture looks to linger Friday and into
the weekend, and rain chances will be enhanced by a difluent flow
aloft ahead of the tropical system. That band and moisture will keep
rain chances high at least through Friday night, and linger into
Saturday across the east, when the upper level and surface lows
should be well east of the Commonwealth. Areal average rainfall
totals look to range from 1-2" across southern Indiana, with 2-4
inch totals possible in Kentucky. Temperatures will be held in check
by the cloud cover, but it will be humid.

Saturday night and into Sunday should be dry, though a few models
bring a front into the region Sunday afternoon/night. The better
performing models in the long range give us isolated to widely
scattered chances for rains. While there is some uncertainty in the
rain forecast, troughing across the region should mean cooler
weather for Sun/Mon.


.Aviation...(12Z TAF Issuance)
Issued at 635 AM EDT Tue Jun 20 2017

VFR conditions are expected through the upcoming TAF period.  High
pressure will build into the region from the northwest today.  A
scattered Cu field will be possible by late morning through the
afternoon with a light westerly wind.  VFR conditions are expected
tonight and into early Wednesday with light and variable winds.




Short Term...MJ
Long Term....RJS
Aviation.....MJ is the U.S. government's official web portal to all federal, state and local government web resources and services.