000
FXUS63 KPAH 092331
AFDPAH

Area Forecast Discussion
National Weather Service Paducah KY
531 PM CST Sun Dec 9 2018

.UPDATE...
Issued at 530 PM CST Sun Dec 9 2018

Updated Aviation discussion for 00z TAFs.

&&

.SHORT TERM...(Tonight through Tuesday night)
Issued at 145 PM CST Sun Dec 9 2018

High pressure over Texas will gradually slide east along the Gulf
Coast over the next couple of days. Any lingering clouds over
southeast portions of the PAH forecast area will move out this
evening, and our region should see mostly clear skies and light
northerly winds overnight. Lows tonight will be in the upper teens
to lower 20s. It will remain chilly on Monday with continued
northerly winds with highs in the upper 30s to around 40 degrees.
Winds will become southwest to south Monday night, and this will
help temperatures moderate Tuesday into Tuesday night. With a lot
of sunshine Tuesday, highs will reach the middle to upper 40s, and
lows Tuesday night will only fall into the lower 30s.

.LONG TERM...(Wednesday through Sunday)
Issued at 234 PM CST Sun Dec 9 2018

A mid level shortwave with limited low level moisture return is
forecast to generate some light rain showers across the PAH forecast
area by Wed afternoon, lingering into Wed night. There is a limited
chance of a wintry mix over southeastern MO/southern IL as the pcpn
ends.

However, on its heels will be a much more significant system. A
deepening low pressure system is progged to dive southeastward out
of the southern Plains and probably into the Deep South before
lifting northeastward over the weekend. The medium range models have
been somewhat erratic with path prediction of the mid level low and
its attendant surface low. The latest trend is for the deterministic
model solutions to merge together a little better overall. The GFS
has been faster and farther north with the path, supported by its
ensemble mean. The ECMWF path was much farther south than the GFS 24
hours ago. However, the 12Z ECMWF bounced back north somewhat from
its 00Z solution. Interestingly, the 12Z CMC model solution appeared
to be the closest to the preferred path of the WPC-drawn surface low
and triple point, which seemed to be the most logical, the low
swinging through LA and toward the northeast through the
Appalachians and beyond, deflecting off a western Atlantic ridge.
The 12Z ECMWF did not show the northeastward path. What appears to
be more certain is that sometime Thu and Fri, we will be in a wet
pattern, with generally 1 to 2 inches of total rainfall expected.
The highest QPF should be along and south of the OH River. Locally
heavy rain is possible, mainly Thu night.

This more southerly path, if it occurs, will mean a slightly cooler
temp forecast for the PAH forecast area, with little chance of
lightning in the warm advection pattern to the northeast of the low
on Thu. This cooler, more stable trend in part is shown in the
latest initialization blend. Deep moisture is expected to wrap
around the vigorous sfc low Thu night, ramping up forecast PoPs and
QPF for especially southern sections of the region. Lift of moisture
will be also enhanced by upper level divergence in the deformation
zone north of the low. Rain is expected to move off the the east Fri
night, leaving the weekend high and dry under a sharp ridge aloft.
Seasonable temps are forecast by then. As pcpn ends Fri night, there
will be a limited chance of a brief wintry mix of pcpn over the
eastern third of the region.

&&

.AVIATION...
Issued at 530 PM CST Sun Dec 9 2018

VFR conditions are expected through this TAF cycle. Some lingering
low VFR cigs near KHOP will move out by late evening. Otherwise,
only high clouds expected through the period. Northerly winds will
remain below 10 kts.

&&

.PAH WATCHES/WARNINGS/ADVISORIES...
IL...None.
MO...None.
IN...None.
KY...None.
&&

$$

UPDATE...SP
SHORT TERM...RST
LONG TERM...DB
AVIATION...SP