Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 301734

Area Forecast Discussion
National Weather Service Louisville KY
1234 PM EST MON NOV 30 2015

...Updated Aviation Discussion...

...Forecast Update...
Issued at 617 AM EST Mon Nov 30 2015

Well...Updated to address current radar and observational trends
with a rain free CWA thru 16z. Last batch of the "Bluegrass rain has
moved past the ERN CWA and the isentropic pcpn over far NWRN cwa has
moved NW into the Land of Lincoln. The High resolution models bring
pcpn back in across far srn tier between 16-18z.

Low MVFR to high end IFR continues with trapped lvl moisture around
stout inversion.  Thus we have CIGS around 1000 ft and easterly
winds.  Depending on how this warm front moves through this
afternoon, I may be too high on afternoon apexes.  My hunch is we
should go 2-3 degrees below what we have, but day crew will have to
monitor the warm sector push.

.SHORT TERM (Now through Tuesday)...
Issued at 255 AM EST Mon Nov 30 2015 active Monday and Tuesday across the CWA.

Through 17Z.. Weak isentropic lift over a weak boundary near the
Ohio Valley will continue to cause light rain shower activity this
morning.  Some of the high res models indicate we could see a better
break in the rain showers toward mid to late morning.

Monday PM...
Sfc low moves swiftly from MCI at Noon to DSM by
midnight and H5 is close to being vertically stacked as it moves NE
from the Rockies into Hawkeye State. Meanwhile a deep moisture plume
continues to stream from the Sooner State thru the Show Me State
toward the CWA providing more moisture for the next wave.

The next surge in moisture will be arriving across Srn KY around
lunchtime initiating steady rain for evening and much of the
overnight across central and southern KY. Will see an increase in
showers everywhere Monday afternoon as a warm front lifts north.
Temps will rise despite clouds and pcpn. There will be a tight
moisture gradient across Srn IN which will be bordering the drier
air. Might be dry in second tier of Srn IN counties.

Many spots south of I-64 can expect about a half an inch
through Monday night, with the highest totals expected near the Lake
Cumberland region (close to 1 inch) and the lower totals more across
central KY. Highs on Monday should recover to the low and mid 50s.

An additional .25" to .75" is expected Monday night with the highest
totals SE and lowest totals NW. Coordinated with JKL to NOT issue a
FFA as none of the QPF amounts are more than 05 inches for each 6
hour block.

.LONG TERM (Tuesday Night through Sunday)...
Issued at 255 AM EST Mon Nov 30 2015

The medium term into the beginning of the extended period will be
dealing with the deep low and thermal trough ahead of the main H5
trough. This trough will pass thru on thru on Thu and the looks
fairly innocuous with some ridging ahead of the next deep low
ejecting out of Rockies next weekend.

Tuesday Night...

Surface cold front will have passed all but the far eastern cwa by
00z. Will keep low chance pcpn in eastern 2 tiers of counties thru
06z. Lows Tuesday night are expected to fall into the mid 30s NW to
the low 40s SE.

Wednesday - Wednesday Night...

Trough axis associated with the potent upper system finally rotates
through the Ohio River Valley by Wednesday evening, returning us to
a cooler/drier pattern. Will have to watch for a few lingering
showers far N and NE on Wednesday, and perhaps enough low level
moisture with modest llvl lapse rates along and N of I 64 to squeeze
out some light precipitation just ahead of the potent trough axis.
will be coordinating with IND and ILN before press time.

Otherwise, despite increased sunshine, temps will be cooler with CAA
aloft yielding only 40s to around 50 for highs on Wednesday.
Wednesday night lows drop to around freezing.

Thursday Night - Sunday...

Keeping a dry forecast with upper air pattern on Euro and the GFS
showing ridging.  Temps appear to be above climo with highs in the
mid to upper 50s.


.AVIATION (18Z TAF Update)...
Updated at 1234 PM EST Mon Nov 30 2015

A significant period of LIFR ceilings is expected at the TAF sites,
with potential to go down near or below minimums shortly after
sunset through a good portion of the overnight. Currently BWG/LEX
are LIFR and are expected to stay there for the remainder of the
afternoon. SDF is right on the MVFR/IFR threshold and will quickly
go to IFR in the next 1 to 2 hours.

Warm front develops over the area and lifts north early this evening
which will help to bring more level moisture into the area,
contributing to the lower ceilings. Vis will also mostly be in the 1
to 3 mile range with a showers beginning to increase in coverage
after sunset. Expect to see some improvement in the pre-dawn hours
as heavier rain helps to "mix" the atmosphere a bit, and cold front
passes through. However, ceilings are expected to stay in the IFR
range. Some heavier rain is expected right around sunrise.

Surface winds will gradually veer through this forecast cycle. They
start out ENE, and will be SE by this evening. They will continue to
veer to southerly overnight, then SW and W by Tuesday.


.LMK Watches/Warnings/Advisories...


Short Term.....JDG
Long Term......JDG
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