Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 040909

National Weather Service Jackson KY
409 AM EST Sun Dec 4 2016

.SHORT TERM...(Today through Monday)
Issued at 408 AM EST SUN DEC 4 2016

Light precip has encompassed our southern CWA and is continuing to
slowly work its way north as it overcomes a layer of llvl dry air.
Temperatures across the CWA are above freezing so far this morning,
so all precip should be falling as rain, even if some wet bulbing is
occurring. However, can`t rule out some of the higher
elevations(generally above 2k ft) still seeing some snowflakes mix
in as temperatures will be a tad bit cooler here at onset, and they
could possibly tap into colder air aloft as well. Overall, continued
to slow down pops through this morning based on the latest radar and
hi-res model trends. It also looks like there may be more of a break
into the afternoon, with a defined southern extent of rain pushing
eastward of the state, and a secondary northern extent moving in
after 21Z. Kept chance pops in otherwise during this time and into
the overnight. Between about 6Z and 10Z (starting in the east), dry
air really begins to pull in aloft as the upper level forcing starts
pushing east of the region and allows cooler drier flow into the
region. This will limit saturation to the lower levels, supporting
more of a drizzle event, before the dry air continues to quickly cut
off remaining precip potential by dawn Monday. Lows Monday morning
should remain just above normal, generally in the upper 30s across
the CWA.

Low level clouds will likely persist throughout the day Monday as
winds near the surface will be from a more NE to E direction
compared to the Wrly flow in the mid and upper levels, keeping
lingering moisture trapped near the surface for much of the day.

A strong upper level low located across TX during the day Monday
will begin to track northeastward as we head into the extended
portion of the forecast. As this occurs, expect another strong pull
of Gulf moisture into the Ohio Valley region, with a surface low
pressure system rotating across Louisiana. This will result in high
clouds building into the region once more from south to north
throughout the day Monday and will help boost temps to just above
seasonable normals in the afternoon despite cloud cover. While
precip chances should generally hold off until after 0Z Tuesday,
there is still a small potential that some pops could overcome mid
level dry air between 18Z Monday and 0Z Tuesday, mainly along the TN
border. As such, did include slight chance to low-end chance pops
here for this time frame.

.LONG TERM...(Monday through Saturday)
Issued at 301 PM EST SAT DEC 3 2016

The extended period looks to be quite active throughout, with a
series of weather systems expected to bring multiple round of
precipitation to eastern Kentucky through the end of the week. The
first area of low pressure is expected to move out of the southern
Plains/western Gulf of Mexico region Monday and Monday night. This
system will bring light to moderate rainfall to the area through
Tuesday, with the highest chance for rain coming from late Monday
night through early Tuesday afternoon. Between three quarters and
one inch of rain is expected across the area through Wednesday
morning, with locally higher amounts possible. We should
experience a brief lull in the active weather during the day on
Wednesday, as our second area of low pressure exits the region. A
third system, however, is on track to move across the area
Wednesday night through Thursday night. This system will bring
quite a bit of cold air into the area on its eastward trek. In
fact, we are expecting minor snowfall accumulations across most
of the area from late Wednesday night through Thursday morning.
Periods of rain/snow mix will then be possible Thursday and
Thursday night, as colder air filters into the region behind the
departing area of low pressure.

Temperatures in the extended will vary greatly. Highs on Monday
and Wednesday should top out mostly in the 40s, with max values in
the 50s on tap for Tuesday, as southerly flow sets up with an
area of low pressure that will be moving across the area that day
and night. After that, however, temperatures will take sharp nose
dive, as a cold air mass settles over the region to end out the
week. Highs on Thursday will top out in the mid to upper 30s for
most locations, with a few spots along the Tennessee border
perhaps breaking 40. The cold air will become firmly established
on Friday, with highs that day struggling to reach or break 30
degrees across the area. Lows Thursday night and Friday night will
likely fall into the teens across the area, as cold westerly flow
sets up across the region.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)

Very tricky forecast overnight and into the day tomorrow. A
mid/upper level wave is expected to impact the TAF sites through
the forecast period, however surface high pressure remains at the
surface with a layer of dry air in place in the low levels. IR
SAT does show high clouds penetrating eastern KY as the system
continues to approach, and should continue to stream across the
region overnight. These clouds are expected to thicken and lower,
but based on latest trends, this may occur a bit later than
originally expected. As of the 6Z TAF issuance, VFR conditions
are expected to persist through 12Z at the southern sites KSME and
KLOZ, but will quickly deteriorate after this point to MVFR
throughout the day as moisture finally overcomes the llvl dry
layer, and rain chances set in. This will occur a couple hours
later at KJKL and KSJS and closer to 18Z at KSYM. Llvl clouds will
linger throughout the upcoming night as well, possibly lowering
further to IFR, even as precip chances begin to taper off.
Overall, winds should remain light and variable throughout the




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