Area Forecast Discussion
Issued by NWS Louisville, KY

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FXUS63 KLMK 221702

Area Forecast Discussion
National Weather Service Louisville KY
1202 PM EST SUN NOV 22 2015

...Updated Aviation Discussion...

...Forecast Update...
Issued at 955 AM EST Sun Nov 22 2015

Light snow/flurry reports in the Bluegrass have ceased and satellite
imagery indicates that low clouds are thinning.  Thus, have taken
the mention of light snow/flurries out of the east.  Skies should
continue to clear from west to east with most locations seeing sunny
skies by early afternoon.  High temps still look to be quite chilly
today in the mid to upper 30s.

Issued at 655 AM EST Sun Nov 22 2015

Getting some reports of snow showers/flurries sneaking under the
radar in the Bluegrass region, where the WNW flow starts to feel the
terrain. It remains a trace event in most locations, but expect it
to continue for the next couple hrs before dissipating around mid-
morning. Otherwise expect temps to remain flatlined, perhaps even a
sunrise dip along and west of I-65 where skies clear first.

.SHORT TERM (Now through Monday)...
Issued at 250 AM EST Sun Nov 22 2015

Next couple of days look unseasonably cold, mainly influenced by an
upper trof currently swinging through the mid-Mississippi Valley and
surface high pressure building from the Southern Plains. Temps
currently around freezing, and fairly uniform across the area thanks
to abundant low clouds and a mixy boundary layer in the NW flow.

Still have a few more degrees to drop before daybreak, and daytime
recovery will be limited due to the mixing that is already going on.
Winds will diminish as the day progresses, but given typical biases
in this pattern will go on the low end of guidance for today`s max
temps, generally in the mid/upper 30s.

Tonight stands to be the coldest night of this run, as winds will
decouple for at least part of the night. Temps will level off as the
surface ridge slips to our south and east, but closest to the ridge
axis in south-central and east-central Kentucky, some of the
sheltered valleys will stay decoupled long enough to bottom out
around 20. Upper pattern flattens out and allows the warming trend
to begin on Monday, but it will take another day to recover to near

.LONG TERM (Monday Night through Saturday)...
Issued at 255 AM EST Sun Nov 22 2015

Zonal pattern Monday night/Tuesday starts to amplify on Wednesday as
a closed upper low digs into the Inter-mountain West, and by
Thursday we start to see better downstream ridging over the eastern
CONUS. Expect several days of dry weather and a gradual warming
trend, with temps recovering solidly above climo by Thanksgiving

Pattern continues to amplify heading into the holiday weekend, with
moisture increasing over the Plains and the Mississippi Valley as S-
SW flow deepens. Bottom line is that it will rain over the weekend,
but timing is the only question. Decent agreement between the GFS
and ECMWF that Friday into Friday night will be wet over most of the
area, but want to see that lock in better from run to run before
bumping POPs any higher than the current 60% chance. Some
disagreement on how quickly the moisture feed is shunted to our
south and east, so will carry chance POPs into Saturday, tapering
down to slight chance in southern Indiana. Expect at least one of
these periods to be bumped to categorical as confidence in the
timing increases.

Cold air will push in from the north as this system exits, with a
strong Canadian high building down the Great Plains. Expect temps
below normal again on Saturday. Way too early to talk about winter
precip, but this appears to be the typical scenario of the cold air
chasing the moisture out of the area.


.AVIATION (18Z TAF Update)...
Updated at 1200 PM EST Sun Nov 22 2015

After KLEX mixes out the MVFR stratus deck currently in place, all
sites will go VFR through the remainder of the TAF period.  This
deck should clear KLEX within the next couple of hours.  Winds will
be out of the NNW this afternoon before becoming light and variable
tonight. Winds will pick up out of the SSW tomorrow at around 10
knots with higher gusts.  A few mid-level clouds may pass mainly
over KLEX and KSDF.


.LMK Watches/Warnings/Advisories...


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