Area Forecast Discussion
Issued by NWS Jackson, KY-- Highlight Changed Discussion --
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FXUS63 KJKL 210744
AREA FORECAST DISCUSSION
National Weather Service Jackson KY
344 AM EDT Fri Oct 21 2016
-- Changed Discussion --(Today through Saturday)
Issued at 344 AM EDT FRI OCT 21 2016
A surface cold front is currently moving through eastern Kentucky,
with widespread precipitation gradually exiting to the east.
Temperatures are running from the mid 50s behind the boundary,
with some lower to mid 60s still hanging on in the far east ahead
of the front. Aloft, an upper level trough axis is shifting
across western KY/TN, with a well-defined dry slot as seen on
water vapor, moving into central Kentucky.
The models are in good agreement through Saturday, with the trough
axis to gradually move east across the rest of the Commonwealth
today. A temporary lull behind the main batch of precipitation
will give way to a resurgence of scattered to numerous shower
activity as the trough moves through our area today. Many high
temperatures will likely be established early this morning, as
cool northwest winds and plenty of low level cloud cover will keep
readings nearly steady in the low to mid 50s through the day, some
30 degrees cooler than the highs from yesterday for many places.
The showers will come to an end from west to east this afternoon
into early this evening. Clouds will likely be slow to dissipate
tonight, with locations west of I-75 seeing the best chance of any
partial clearing by dawn Saturday morning. Lows will be in the
lower 40s for most spots, with the exception of the higher terrain
in the southeast, where 30s will be more commonplace. A few sites
out west may also be candidates for some 30s if enough clearing
can take place late.
Saturday will feature a partly cloudy day, with highs in the mid
to upper 50s, as high pressure builds in from the west and
southwest, and heights recover aloft.
.LONG TERM...(Saturday night through Thursday)
Issued at 344 AM EDT FRI OCT 21 2016
Models are in good agreement from Sunday night through much of the
upcoming week. High pressure will be positioned just to our south
at the start of the period, leading to the coldest night of the fall
Saturday night into Sunday morning. Lows should settle into the mid
30s in the colder sheltered valleys with readings in the lower 40s
on the ridgetops. This high pressure will be pushed south as a dry
cold front slips south Sunday night into Monday. Ahead of the front
on Sunday, temperatures should have a nice bump with a nice surge of
higher mid level heights. The cold front won`t have a significant
impact on the weather, expect to bring in a very dry airmass for
Monday and Tuesday. Fortunately, with high pressure settling in
across the region, winds should stay fairly light both days, so no
significant fire weather concerns. Tuesday morning could turn quite
chilly with the very dry airmass and we could be looking at our
first good frost for the area, but ECMWF remains a bit higher on
dewpoints, which could favor more fog formation. Regardless, could
be some spotty frost in places. Doesn`t appear widespread enough to
warrant a mention in the HWO at the moment. Temperatures will again
rebound into the middle of the upcoming week as high pressure slides
east and we start to see return flow.
A shortwave trough will cross the great lakes late Wednesday into
Thursday and will help to drag a cold front across Kentucky again.
This time around, moisture looks more limited, but there will be a
small chance for some showers as the front pushes through on
Thursday. 00z GFS actually weakened the system a bit, but ECMWF
maintains some light QPF areawide. Details are a bit more fuzzy
behind the Thursday system as models support a very weak push of
colder air, so we may stay mild into the end of the week, but the
00z ECMWF does bring a secondary cold front south Thursday night and
could bring some cooler temperatures heading into next weekend.
Latest GFS does not support that solution, so still some spread with
respect to those details.
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.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 203 AM EDT FRI OCT 21 2016
A cold front has moved east of a line from KSYM to KLOZ. This will
continue to move through the rest of the area over the next 1 to 2
hours, with southwest winds of 5 to 10 kts shifting to the
northwest at 10 to 15 kts, with gusts to around 20 kts for about
an hour. Ceilings will drop down to IFR, with rain showers
continuing through around dawn, before becoming more scattered
from west to east during the day. Ceilings will gradually raise up
to MVFR through the day, before becoming VFR towards dusk for most
locations. Northwest winds will become gusty once again during
the afternoon, before diminishing by early evening.