Area Forecast Discussion
Issued by NWS Paducah, KY
FXUS63 KPAH 271130
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PADUCAH KY
530 AM CST Tue Jan 27 2015
Updated aviation section for 12z tafs
.SHORT TERM (Today through Thursday night)...
Issued at 308 AM CST Tue Jan 27 2015
A 500 mb vorticity lobe was racing southward in very strong
northerly flow aloft on the back side of the major noreaster. This
feature was producing some light freezing rain or mixed precip
from kevv and kowb northward as of 08z. The precip will end by 12z
per radar and model data output. Radar returns have been weakening
the past couple hours, so there does not appear to be a need for
an sps product.
The main concern for today is cloud cover and its effect on temps.
Satellite and surface reports show overcast skies across the
entire state of Indiana and most of Illinois. Northerly flow
should tend to hold this overcast over sw Indiana/se
Illinois/Pennyrile of west KY most of today. This will limit temp
rises to just 5 to 8 degrees. Further west, skies are clear across
much of se Missouri early this morning. There should be a good
deal of sun today in the kpof area, where 850 mb temps will be
above freezing. Therefore, a rather strong temp gradient is
expected from west to east this afternoon.
A gradual clearing trend is expected across the entire region
tonight as deep layer ridging builds east in the wake of the
noreaster. Low temps will be in the 20s.
On Wednesday, the deep layer ridge will build across the Ohio
Valley. This should result in plenty of sun and somewhat milder
A cold front will move southeast across Missouri Wednesday night
and the Lower Ohio Valley on Thursday. The forecast models are
mainly dry with the frontal passage until it reaches our area. The
00z ecmwf develops light rain along the front over se Missouri Wed
night. The gfs/sref/nam delay the development of precip until the
front crosses the Mississippi River. Even then, most of the precip
is east of southern IL and far west KY. Will continue with small
pops with this system.
Thursday night should see clearing skies and a little colder air,
with lows around 30. The high pressure system in the wake of the
front will be relatively weak.
.LONG TERM (Friday through Monday)...
Issued at 308 AM CST Tue Jan 27 2015
High pressure will result in dry and seasonal weather Friday into
Friday night. Models for 12z Saturday have an upper low over the
SW U.S. that partially consolidates with the dominant northern
branch by 12z Sunday. Prior model runs of the past few days showed
more of a NW flow influence across our area, with precip
probabilities more uncertain. However the trend is wetter, as the
models show abundant moisture streaming ENE and into the area late
Saturday through Saturday night. The aforementioned low should
cutoff over Baja. Meanwhile an upper trof is forecast move from the
Plains and across the area Sunday/Sunday night. Raised PoPs ahead of
this feature, especially for Saturday night into Sunday. As far as
precip type, the 00z ECMWF has trended milder, and the 00z GFS is
mild. Kept R-S- mention northern areas, but just rain south for
now. On the backside of the system Sunday night, will indicate a
small chance of light snow, then return dry weather Monday as the
upper system and associated surface low head off to the NE U.S.
Temps were a blend of MOS and previous numbers, except for Saturday
night into Sunday. In that time frame more weight was given to the
base model output.
Issued at 530 AM CST Tue Jan 27 2015
Satellite imagery shows that skies cleared out over a large portion
of our region overnight. The exception was in the kevv/kowb area,
where cigs fell below 5 hundred feet. With daytime heating, expect
cigs to start rising by mid-morning, reaching mvfr thresholds by
late morning. At kpah/kcgi, a stratocumulus deck should develop
gradually this morning, with mvfr cigs likely by midday. At all
sites, skies will clear out tonight. The timing should be early at
night in the kcgi/kpah areas, and possibly well after midnight in
the kevv/kowb areas.