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fxus63 kpah 160500 
afdpah

Area forecast discussion
National Weather Service Paducah Kentucky
1100 PM CST sun Dec 15 2019

Update...
issued at 1057 PM CST sun Dec 15 2019

06z aviation update.

Update issued at 810 PM CST sun Dec 15 2019

Freezing line at 8 PM was from Wayne and cape counties in
Missouri, to Marion and Carmi in southern IL, to Gibson and Pike
counties in southwest in. Seeing light precip continuing in these
areas with temps 30 to 32. So, the concern for light freezing
drizzle or very light freezing rain continues. So far, not
receiving any reports of any issues. Earlier, we did see around 1
inch of snow along and north of I-64, but no real travel issues.

Lower pops for the overnight north and west of the Ohio. In the
advisory area in semo, southern IL, the concern for lingering
freezing drizzle will persist. South into west KY, we will
continue to see occasional light showers, and possibly thunder up
toward the Tennessee border. The Gibson, Pike, White County advisory
ending at 11 p.M. May need a revisit if temps remain below 32f
will have to make a decision on that soon, largely based on
anticipated temperatures.

Update issued at 515 PM CST sun Dec 15 2019

00z aviation update.

&&

Short term...(tonight through Monday night)
issued at 215 PM CST sun Dec 15 2019

The forecast appears to be in pretty good shape. The main concern
is still some light wintry precip amounts north and west of the
Ohio River. Secondary concern is heavy rainfall and minor flooding
issues in the pennyrile region of west Kentucky.

As of mid afternoon, the main story was the low-level dry air
inhibiting precip. Radar indicated banded echoes up to 30 dbz over
the Interstate 64 corridor of southern Illinois and southwest in.
Despite the persistence of these bands, only trace amounts have
reached the ground at kmvn so far. The high-res models indicate
these bands may yet produce a tenth of an inch of precip (liquid
equivalent) north of Interstate 64 by this evening. Ptype would be
mainly snow due to evaporational cooling of the column. A quick
inch of snow remains possible by this evening north of I-64.

Attention then turns to the development of widespread stratiform
precip by 00z across the whole forecast area. Surface temps have
risen above freezing across nearly the entire forecast area except
the I-64 corridor. Temps aloft will be quickly on the upswing as
southwest flow increases above 900 mb. A period of overrunning
precip early tonight should be mainly rain. The exception is in
the advisory area, generally northwest of a kcgi to Mt Carmel
line. A shallow northeast flow of cold air will keep surface temps
there near freezing through early Monday. Due to the potential
for some minor icing in that area, the advisory will be allowed to
continue.

By midnight, precip will end or taper to light drizzle across all
but the pennyrile region of west Kentucky. There may be some light
freezing drizzle in the advisory area. The lull in the precip will
last into early Monday morning.

Another surge of precip associated with the main upper low will
arrive by midday Monday. The 850 mb low will track close to the
Interstate 64 corridor, keeping the elevated warm sector over our
entire forecast area. Surface temps are forecast to climb just
above freezing in the advisory area by midday. Periods of rain are
forecast through the afternoon. Closer to the elevated low level
jet and instability axis, isolated thunder and heavy rainfall is
possible in the pennyrile region of west Kentucky. Storm total rainfall
there will be in the 1 to 2 inch range in the pennyrile (khop
area). This warrants enough concern to mention in the severe weather potential statement.

Monday night, the low-level flow will turn northwest behind the
departing low. Deeper cold air will be drawn back into our area.
The precip will be ending, but probably not before a change back
to light snow or freezing rain in southern Illinois and parts of
southeast MO. Later shifts may determine there is enough of a
concern to warrant another advisory issuance for Monday night. The
primary concern is some light icing, mainly in the same counties
that are in the current advisory.

Long term...(tuesday through sunday)
issued at 215 PM CST sun Dec 15 2019

At the beginning of the forecast period on Tuesday, the area of low
pressure that bought our wintry weather will be well to our east.
Cloud cover will be plentiful to start the day, and some isolated
flurries or even freezing drizzle could be possible. However, skies
will clear in the afternoon as Arctic high pressure arrives.
Northwesterly winds could be a bit breezy at times.

With an airmass with Arctic origins arriving, a period of chilly,
below-normal temperatures is expected Tuesday and Wednesday. Highs
on Tuesday will range from 33 around kmvn to 41 at kpof. Combined
with a brisk northwesterly wind, wind chill values will be in the
lower 20s to lower 30s. Morning lows Wednesday will range from the
upper teens in our north to lower 20s along the Arkansas/Tennessee borders.
Temperatures will recover slightly on Wednesday.

On Thursday, the high pressure will shift east of the area, and
southerly return flow will allow temperatures to moderate closer to
normal values for Thursday through the weekend. Confidence is
slightly higher compared to yesterday that we'll stay dry through
the weekend. Models have trended towards keeping the disturbance
progged to develop near the central rockies south of our region.

&&

Aviation...
issued at 1057 PM CST sun Dec 15 2019

Widespread IFR/LIFR conditions to persist tonight and into Monday.
Light rains and drizzle will persist, with some freezing drizzle
possible northwest of a kcgi-kfwc line, mainly impacting kmvn.
Thunder may be close to the Kentucky/Tennessee border tonight with activity not
too far south of kucy. Winds will continue north to northeast 5 to
10 kts, then increase Monday to 8 to 12 kts with some higher
gusts. Mainly all liquid precip Monday, then a transition back to
a wintry mix is possible again mainly impacting areas around kmvn.

&&

Pah watches/warnings/advisories...
Illinois...Winter Weather Advisory until noon CST Monday for ilz075>078-
080>082-084-085-088.



MO...Winter Weather Advisory until noon CST Monday for moz076-086-087-
100-107.

In...none.

Kentucky...none.
&&

$$

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