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Area forecast discussion 
National Weather Service Paducah Kentucky
350 am CST Fri Jan 30 2015

Short term...(today through Sunday night)
issued at 314 am CST Friday Jan 30 2015

Well, the main forecast challenge today continues to lie with the
weekend storm system. Confidence is increasing that this will be
mainly a rain event over much of the region. Model trends over the
past 24 hours now have been to shift the sfc low farther and
farther to the north across MO/Illinois Sat night/sun. This would put
most of our forecast area in a warmer low lvl southeasterly flow
regime, which does not Bode well for significant winter weather in
this region. In fact, it now appears as though some locations of
wrn Kentucky and se MO may top 40 degrees Sunday. Due to recent model
trends, will shift the rain snow mix area northward to up around
the I-64 corridor.

As far as rain amounts are concerned, upward of a half inch of
rain will be possible over many locations. Conditions could be
similar to last Sunday, when it rained steadily much of the day.

Long term...(monday through thursday)
issued at 314 am CST Friday Jan 30 2015

A couple of short-lived cold blasts will be the main story in the
long term. Precipitation potential will be low due to the lack of
moisture in the predominantly northwest upper flow pattern.

As far as the daily details...
on Monday...the first cold blast will be fully underway in the
morning. 850 mb temps will be in the minus 10 to minus 15 range
early in the day. Forecast soundings from the GFS indicate very
steep lapse rates and plenty of moisture in the low levels. This
could result in some cold advection flurries as well as gusty
surface winds. Guidance is in fairly good agreement that highs will
be only in the mid to upper 20s in most areas. Clearing is expected
during the day as a 1032 mb high builds east across Illinois.

On Monday night and Tuesday...low level winds will back into the
southwest as the high crosses the Appalachians. 850 mb temps will
respond very rapidly. In fact, the 00z GFS/ECMWF show 850 mb temps
warming about 20 degrees celsius over a 48 hour period. Highs on
Tuesday should be in the lower 40s in most areas with plenty of sun.

On Tuesday night and Wednesday...a clipper type system will pass
well north of our region. There may be just enough moisture and lift
for some light rain or snow as the associated cold front approaches
from the northwest. The timing of the cold front varies widely from
model to model, which results in a large range of temp guidance for
Wednesday. The 00z GFS and ECMWF MOS both show temps in the low to
mid 50s at kpah on Wednesday. Will nudge temps upward for Wednesday,
but not nearly that much.

On Wednesday night and Thursday...a second blast of cold air will be
arriving. The 00z model suite indicates this cold blast may not be
as strong as that on Monday. Timing differences are huge at this
time range. The 00z ECMWF indicates the cold front may not even be
through western Kentucky Thursday morning. The forecast will follow
the faster models, which show the cold, dry air well-entrenched over
the lower Ohio Valley and southeast Missouri.

&&

Aviation...
issued at 1132 PM CST Thursday Jan 29 2015

Quite frustrated with the higher VFR ceilings than forecast, but
the expected ceilings near 3kft agl +/- 500 ft are finally coming
to fruition. Plan to keep these ceilings in place through at least
14z. Shortened the period of ceilings by 3-5 hours, before
clearing out.



&&

Pah watches/warnings/advisories...
Illinois...none.
MO...none.
In...none.
Kentucky...none.
&&

$$

Short term...GM
long term...my
aviation...Smith

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