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fxus63 klmk 231301 

Area forecast discussion
National Weather Service Louisville Kentucky
901 am EDT Sat Jun 23 2018

Forecast update...
issued at 900 am EDT Sat Jun 23 2018

Getting some light rains over our southern Indiana counties at this
time. Updated the forecast for these showers. Otherwise have
clearing over our southern Kentucky counties and our next
disturbance in coming in from the west. Would expect a few isolated
cells to develop around lunch time down there, with coverage picking
up by mid afternoon. As for severe potential, latest NAM/rap show a
mid-level jet crossing the Tennessee Valley later this afternoon. Any
storms that develop in the 4-8 PM time frame across southern
Kentucky may be able to take advantage of this wind energy and drop
some stronger gusts.


Short term...(today and tonight)
issued at 333 am EDT Sat Jun 23 2018

Area radars were generally quiet across the region this morning with
partly to mostly cloudy skies. A few showers have recently
developed just north of the Lake Cumberland region. These should
continue to track on off to the east. Temperatures were generally
in the mid to upper 60s in most locations. Not expecting much
change in the weather over the next few hours. In general, we
expect mostly cloudy skies in most areas as low-level stratus builds
downward. Temperatures should remain in the mid-upper 60s through

For today, we'll probably start off the day with mostly cloudy skies
across southern Indiana and in much of northern Kentucky. Upper low
to the north will continue to pull away from the region. However,
eyes will turn to the west as a fast moving upper level disturbance
pushes eastward out of the plains and toward our region this
afternoon. Most cams suggest scattered thunderstorms once again
developing, but generally favoring areas south of here in the
Tennessee Valley. So for now, have capped pops around 20 percent
across southern in/northern Kentucky with chance pops downstate. Highs
should be slightly warmer today with readings in the upper 70s to
the lower 80s across southern in and northern Kentucky. Mainly lower 80s
are expected across southern Kentucky. The warmest readings will
generally be along the Kentucky/Tennessee border.

For tonight, upper level impulse shifts east of the region and we
should see a downtick in convective chances for a short time.
However, next upper level perturbation will arrive late tonight
yielding an uptick in shower/storm chances as we head toward sunrise
Sunday morning. Lows tonight will generally be in the upper 60s to
around 70.

Long term...(sunday through friday)
issued at 321 am EDT Sat Jun 23 2018

A weak cold front will begin sliding into the lower Ohio Valley on
Sunday. Combination of an unstable air mass south of the front and a
weak wave riding within the quasi-zonal 500mb flow should be enough
to spark some showers and storms during the day and evening. Shear
may be strong enough to support some multi-cell clusters and bowing
segments, with the main threats being gusty winds, small hail and
heavy rainfall in the strongest storms.

The latest 00z guidance now stalls the front somewhere across
central or northern Kentucky by Monday morning, with it retreating
northward as a warm front during the day Monday. Warm and muggy
conditions look to persist, though a passing shortwave trough on
Tuesday/Wednesday could spark some showers and storms to provide
temporary relief from the warm temperatures.

A strong upper level ridge over the Desert Southwest will build into
the eastern US for the end of the work week, bringing even warmer
temperatures. Dewpoints look to stay high through the end of the
week as well, so heat indices could approach or exceed 100 degrees
during this time.


Aviation...(12z taf issuance)
issued at 639 am EDT Sat Jun 23 2018

VFR to MVFR ceilings are expected across the forecast area this
morning as low-level moisture pivots across the region. We should
see ceilings start to lift and scour out a bit by mid-late morning
and into the afternoon hours. Winds this morning will be out of the
southwest at 4-8kts.

Upper level disturbance over the plains will slide eastward this
afternoon and kick off another round of afternoon/eve showers and
storms. Best coverage looks to be across west Tennessee and perhaps into
far southern Kentucky. For now, plan on mentioning just a period of thunderstorms in the vicinity
between 23/18-24/00. We should see a break in the action into the
early overnight hours. However, a secondary disturbance will move
into the region toward the end of the period resulting in more
convective development as we head towards 24/12z.


Lmk watches/warnings/advisories...


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