Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 140805

Area Forecast Discussion
National Weather Service Louisville KY
305 AM EST Sat Dec 14 2019

.Short Term...(Today and tonight)
Issued at 230 AM EST Sat Dec 14 2019

Upper level trough slides to the east as the associated storm system
moves up through New England taking the associated precipitation
with it into eastern KY and out of the area through Saturday
morning. Some patchy fog is possible across the area thanks to the
rain but mixing should keep most of it as low stratus during the
morning hours.

We will be between systems for the day Saturday into Saturday night
with high pressure building in to our north across the Dakotas and
MN Saturday and Saturday night. Clouds will remain and as some
cooler air filters in behind the passing system temperatures hold
steady in the lower to middle 40s. It remains dry and generally
cloudy Saturday night into Sunday morning as temperatures fall into
the mid to upper 20s to near 30 degrees by Sunday morning.


.Long Term...(Sunday through Friday)
Issued at 300 AM EST Sat Dec 14 2019


Sunday through Tuesday Night...

Sunday will start off mainly dry as we will be in between weather
systems.  By Sunday afternoon the next weather system will approach
from the west. A warm front is expected to develop generally across
Tennessee on Sunday afternoon.  A sharp increase in moisture and
isentropic lift will take place in the afternoon and precipitation
should develop across the region.

Model proximity soundings have been trending slightly warmer in
response to the stronger 850 hPa flow across the region.  Initial
precipitation will likely be rain across much of Kentucky.  However,
a wintry mix of rain/sleet/freezing rain/snow will be possible
across southern Indiana and far northern KY Sunday evening for a few
hours.  The best chance of wintry weather looks to remain north of
the I-64 corridor.  This wintry mix may be able to produce some
minor accumulations of snow, but that will really depend on surface
temperatures and how long the precipitation stays in frozen form.
Based on the latest model trends, the wintry mix does not look to
last all that long as the strong 850 hPa flow and warm advection
will quickly win out changing precipitation across our area to rain
by midnight.  Temperatures look to continue to rise overnight as the
warm front lifts northward.

For the day on Monday, the warm front looks to lift northward toward
the Ohio River before the surface low treks northeastward through
the region.  Strong moisture convergence along and just southeast of
the low will bring plenty of rain shower activity to the region.
Some embedded thunderstorms will be possible, however, the
widespread cloud cover and precipitation will probably be too great
to result in much instability.  Rainfall amounts of of 1 to 3 inches
look likely with the heaviest QPF just along the low track.  The
models vary with their placement, but current thinking is that the
heavy rainfall axis could be just on either side of the Western
Kentucky and Bluegrass Parkway corridor.  The rainfall could be
heavy enough at times to result in some minor flooding in the
typical low spots and poor drainage locations.  In addition to the
rainfall, we`ll see breezy conditions across the region.

As for temperatures, we`ll see a strong gradient across the region
with afternoon temperatures readings ranging from the upper 30s
across southern Indiana to the lower 60s over southern Kentucky.

Rainfall will continue into Monday night though the heavier activity
will likely be over in far eastern KY and Tennessee.  Behind the low
pressure system, colder air will work into the region overnight.
This colder air will again be chasing the departing precipitation
shield so a little bit of snow could fall on the backside of the
system.  Lows Monday night will fall back into the upper 20s to the
lower 30s.

High pressure will start to build into the region on Tuesday.
Initially cloudy skies will be seen, but clearing should take place
during the afternoon with highs staying in the mid-upper 30s over
southern Indiana and northern Kentucky with lower 40s over southern
KY.  With clearing skies expected Tuesday night, lows are likely to
drop into the upper teens to the lower 20s.

Wednesday through Friday...

The upper trough responsible for the Sunday-Tuesday active weather,
is forecast to move off to the east on Wednesday and upper level
ridging will build into the area.  We expect dry, but cool
conditions initially on Wednesday with a moderation in temperatures
through the end of the week.  Highs on Wednesday will average in the
low-mid 30s across southern Indiana and the northern half of
Kentucky.  Southern KY looks to stay mainly in the upper 30s.
Overnight lows will bottom out in the upper teens to the low 20s.
Thursday and Friday will see highs warm up quite a bit with readings
in the mid-upper 40s with overnight lows in the upper 20s to the
lower 30s.


.Aviation...(06Z TAF Issuance)
Issued at 1240 AM EST Sat Dec 14 2019

Widespread rain continues to be see on on radar across the region.
Observations at TAF sites continues to show a mix of LIFR and IFR
conditions due to the continued flow of Gulf moisture being lifted
into the region. This trend continues overnight with continued mix
of CIGs in the the IFR and LIFR with patchy fog. These conditions
continue to near field mins at times. Bulk of the rain will stay
south and east of HNB, but steady light rain is expected to continue
into daybreak Saturday morning. OVC conitions continue with CIGs
lifting to MVFR by late morning and earl afternoon. There could be a
a few hours of VFR Saturday afternoon but MVFR CIGs are expected to
return Saturday night.




Short Term...BTN
Long Term...MJ
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