Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 191047

647 AM EDT Sun Oct 19 2014

...Updated Aviation Discussion...

.SHORT TERM (Now through Monday)...
Issued at 309 AM EDT Sun Oct 19 2014

Low clouds continue to linger over the region with moisture mostly
trapped below 925 mb. The NAM has handled these low clouds the best
for the past 24 hours, and would suggest they will linger along and
east of I-65 into the mid and late morning hours at least. They
could hold on in our NE (including Lexington) until mid to late
afternoon. This matches up with 0-3 km temperature forecasts showing
thermal ridging only slowly pushing east during this time, and no
other mechanism to eradicate them other than daytime mixing.
Therefore, will be pretty pessimistic with the cloud forecast and
today`s temperature forecast across our north and east. Also, have
removed any chances for patchy frost early this morning as
temperatures are currently running in the 46-51 range.

Surface high pressure settles over the area today with benign
northwest flow aloft. Expect highs to reach up around 60 in our SW,
and only reaching the mid 50s in our NE due to the cloud cover.

Focus will shift to another PV anomaly dropping SE in the northwest
flow late tonight. Expect an increase in upper level clouds this
evening ahead of the feature, however as we near sunrise on Monday
some slight chances for a measurable rain shower will be possible
across southern Indiana. Not totally sold on the prospects of
measurable precipitation as organization of "deeper" moisture
appears in question. The NAM (which has performed well over the past
24 hours) keeps us dry, so will hesitate on any higher pops for now.
Either way, the best chance for a light rain shower will be across
our northeast CWA from early Monday morning through the day. Do
expect a warm-up for Monday with highs reaching the low and mid 60s
on steady SW flow at the surface.

.LONG TERM (Monday Night through Saturday)...
Issued at 245 AM EDT Sun Oct 19 2014

Amplified upper pattern will have the Ohio Valley in deep northerly
flow Monday night and Tuesday, keeping us cloudy and a bit
unsettled, especially across the Bluegrass region. Even with the
cold front already through, and most of the mid/upper forcing
remaining to our north and east, models show a decent moisture plume
off Lake Michigan. Will keep small POPs and low QPF in through
Tuesday, with the best chance over the Bluegrass and into the higher
terrain near Lake Cumberland.

Closed upper low is slow to exit the mid-Atlantic but a shortwave
ridge aloft tries to build in by Thursday. Canadian surface high
will nose south into the Ohio Valley, providing dry weather and cool
temps. Eventually a chunk of this high will break off the parent
high and modify over the Ohio Valley. By the weekend temps should
recover to climo or just a couple degrees warmer. No precip in the
forecast as a late-week upper system is shunted well into the Deep
South without the Gulf ever opening up.

Only real chance for frost will be on Thursday morning, when the
surface ridge is closest to central Kentucky. Current forecast is
for upper 30s in much of the area, so it wouldn`t take much of an
adjustment for frost to be in play, especially for rural locations.
Stay tuned.


.AVIATION (12Z TAF Update)...
Updated at 647 AM EDT Sun Oct 19 2014

A stratocu deck continues to impact the SDF/LEX terminals, and is
expected to persist at least through mid day. Ceiling heights are
expected to stay above fuel-alternate, although in the MVFR range.
BWG will likely bounce between VFR and MVFR as it is on the fringe
of the low level moisture.

Ceilings will begin to rise and scatter around midday, with a return
to VFR. Meanwhile, light and variable winds will rule as surface
high pressure settles over the region.

A light southerly wind will become established tonight on the back
side of the high pressure, with plenty of mid and upper level clouds
streaming in ahead of the next system. Small chances for a light
rain shower are expected toward dawn on Monday, but with little, if
any, impacts won`t mention in TAFs yet.




Short Term........BJS
Long Term.........RAS
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