Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 301049

Area Forecast Discussion
National Weather Service Louisville KY
649 AM EDT SAT APR 30 2016

...Updated Aviation Discussion...

...Forecast Update...
Issued at 637 AM EDT Sat Apr 30 2016

The next round of rain is now pushing into southwestern portions of
central KY. Timing the leading edge of this band puts it into
Louisville around 8-8:30 and the northern Bluegrass about an hour
later than that. Hourly pops were adjusted a bit to reflect the
current radar trends and latest forecast based on mesoscale models.
Have lowered pops just a bit across the far eastern portion of the
forecast area.

.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 (12Z TAF Update)...
Updated at 649 AM EDT Sat Apr 30 2016

A large area of showers was moving northeast through western
Tennessee and Kentucky at 1030Z. Ceilings were generally MVFR in the
heavier rain areas - from BKN018 at KPAH to BKN032 at KHOP.
Visibility at KPAH dropped to 2 1/2 SM, but KHOP only fell to 5 SM.
Current motion puts the leading edge of this line into KSDF by
1245Z. Thunder lags about 50-70 miles behind the leading edge, and
has not shown as consistent a trend in moving northward, so will
hold off on introduction of VCTS for a few hours, which places it in
line with previous TAF issuance.  For now will hold off on reducing
CIGS and VSBY below level from 06Z TAF issuance, but these may need
to be adjusted downward into MVFR values at KSDF this morning.


.LMK Watches/Warnings/Advisories...


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