Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 301721

Area Forecast Discussion
National Weather Service Louisville KY
121 PM EDT SAT APR 30 2016

...Updated Aviation Discussion...

...Forecast Update...
Issued at 905 AM EDT Sat Apr 30 2016

Adjusted pops this morning to account for the latest radar trends. A
band of moderate showers and a few thunderstorms associated with
strong moisture advection on the nose of a 50+ low-level jet
continues to push northeast through the region.  Pops have been
upped to 100% to account for this slug of moisture.  The latest
guidance suggests clouds/precip will linger in the northeastern CWA
through a good part of the afternoon, which will limit thermodynamic
recovery. It was discussed with SPC to trim the Slight Risk further
to the west closer to the I-65 corridor, but will wait and see how
these morning showers/storms play out and look at the 12Z guidance
before making adjustments.

.SHORT TERM (Now through Sunday)...
Issued at 324 AM EDT Sat Apr 30 2016

The short term period will bring multiple chances for showers and
storms to the region, some of which could be strong. For today a low
pressure system will track from TX/AR into MO/IL. The warm front
associated with this system will lift north across the region today
with most of the region making it into the warm sector by late this
afternoon or early this evening.

Isentropic lift has brought some light showers to the region this
morning. This initial band of showers will continue to lift north
and scatter out. A band of more widespread showers and some
thunderstorms are then expected to lift north through the region
from around sunrise through mid to late morning. With fairly decent
coverage of showers expected with this band, will keep pops this
morning in the 70-90% range.

There should be a break in the precipitation as the warm front lifts
north through mid day. The question for this afternoon and evening
will then become how much the area can destabilize. Models do depict
decent shear profiles this afternoon as winds aloft increase.
However, cloud cover could limit destabilization, particularly
surface based instability. Still, thunderstorms are expected to
develop once again this afternoon. A few of them could become strong
to severe with hail and damaging winds. Think the best chance for
stronger storms will be across southwestern portions of central KY
as this area will get into the warm sector first. Storms should then
be decreasing through the early overnight hours.

The area will still be in the warm sector on Sunday. Instability
looks to be greater on Sunday. However, wind profiles will not be as
favorable for stronger storms as they are today. Still, there will
be a chance for some strong to marginally severe storms once again
Sunday with large hail and strong winds.

.LONG TERM (Sunday night through Friday)...
Issued at 336 AM EDT Sat Apr 30 2016

A low pressure system over the Great Lakes region will swing a cold
front through on Sunday night. This should bring an end to any
showers and storms from Sunday. However, will have to watch a wave
coming up from the south that has the potential to bring some rain
to east central KY on Monday. For now will keep the forecast dry
during the day Monday with some slight chances for precipitation
Monday night, but pops may eventually be needed during the day as
well. Monday will be cooler with highs only in the mid 60s to lower
70s. Tuesday looks to be dry as well with similar highs to Monday.

For the second half of the work week a deep trough looks to build
into the eastern CONUS. A cold front will bring the chance for some
rain on Wednesday into Wednesday night. Impulses wrapping around the
upper low cloud then bring some showers to the Bluegrass region for
the end of the week. Temperatures do look to be cooler for the end
of the week with highs in the mid 60s and possibly cooler than that
on Friday.


.AVIATION (18Z TAF Update)...
Updated at 119 PM EDT Sat Apr 30 2016

Deep moisture continues to pump into the region, resulting in a band
of showers and a few thunderstorms.  The showers and isolated storms
should begin to taper off at BWG and SDF in the next couple of
hours, lasting at LEX until later this afternoon.  However,
additional shower/storm activity is expected to develop over western
KY late this afternoon, moving into all sites this evening into the
early overnight hours.  Confidence is not very high in this scenario
given the widespread rain/clouds limiting instability currently,
thus will go continue with just VCTS/TEMPO wording.  Winds will be
out of the ESE through this evening, veering to more SSW overnight.

Any storms should clear out by Sunday morning, leaving VFR
conditions.  However, additional thunderstorms will be possible
Sunday afternoon in the SDF planning period.  Winds will increase out
of the SSW through the day to around 10-15 knots.


.LMK Watches/Warnings/Advisories...


Short Term.....EER
Long Term......EER
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