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Area forecast discussion 
National Weather Service Paducah Kentucky
242 PM CDT Tue Sep 2 2014

Short term...(tonight through Thursday night)
issued at 241 PM CDT Tuesday Sep 2 2014

A weak mid/upper-level trough pushing through the area today, has
pushed a weak surface wind shift into our western counties this
afternoon. There has been some drying/mixing of dewpoints, and
temperatures have struggled to warm up behind this wind shift from
kpof through kmvn. Scattered convection is to be expected ahead of
this front over southwest Indiana and west Kentucky through

Skies are expected to clear and winds will become slack by
late evening over the entire region. This certainly could result
in fog development throughout the region overnight. Did not
mention it in the gridded forecast at this time. Just prefer to
see the clearing and diminished winds before putting fog in the
official forecast.

The 12z guidance builds the 500mb heights over our region
Wednesday into Thursday. Today's surface boundary will take on
more of a warm frontal look Wednesday, and it may provide a focus
for convective development mainly over the western half of the
area Wednesday afternoon. This is likely to be isolated to widely
scattered development, if anything.

It looks like the heat and humidity will reprise its role on
Thursday, with temperatures climbing well into the 90s and
dewpoints holding above 70 degrees. Much of the area will see
heat indices around of just above 100 degrees Thursday afternoon.
It should stay under heat advisory criteria, so will continue to
just mention the near-advisory level heat in the severe weather potential statement.

The forecast is dry from Wednesday night through Thursday night,
which seems reasonable with the high building overhead. However,
one model or another tries to generate some isolated quantitative precipitation forecast throughout
this period. Certainly cannot rule out diurnal development with
the building heat and humidity, but confidence and expected
coverage are too low to mention at this time.

As for temperatures, decided to lean toward the warm side of
guidance in general throughout the short term period for both
highs and lows. This is especially the case with highs for Thursday.

Long term...(friday through tuesday)
issued at 241 PM CDT Tuesday Sep 2 2014

Medium to high confidence in the extended.

Models are in good agreement with the upcoming cold front towards
the end of the week. The 12z Tue GFS is a bit slower than its
counter part 12z European model (ecmwf) with moving the front through the region.
They both have similar arrival but the GFS has slower departure and
cool air arrival. Either way Friday and Saturday look to be
plentiful with thunderstorms. Surface based Li's negative 7 and cape
between 2k and 3k j/kg severe weather can not be ruled out.
Mitigating factors for severe weather would be a freezing level near
15k feet would lessen the possibility of hail. In addition low shear
with relatively light winds overall would also negate tor's and
super cells overall. Multi cellular with heavy rains as pwat's
approach 2"...would indicate heavy rain possibly a severe wind would
be the main threat with this frontal passage.

Otherwise much cooler and drier is expected in the wake of this
front by Sunday. Temps will be around 10 degrees cooler than prior
to passage.


issued at 1247 PM CDT Tuesday Sep 2 2014

A weak convectively-generated disturbance will move eastward
through the region this afternoon. Any related convective
development should be to the south and east of the terminals. Some
lower ceilings are expected to push eastward into kevv and kowb
this afternoon, but they should stay above 3kft. A few gusts from
the west cannot be ruled out through the afternoon.

There is some short term guidance that develops convection in the
vicinity of kcgi and kpah early this evening, but confidence is
too low to mention in either terminal at this time.

With clearing and light winds expected this evening, fog or low
cloud development is a real possibility. Left the inherited IFR or
lower fog as it was in the previous forecast for kpah and kevv.
Added a scattered low deck to the existing fog in the kevv and
kowb forecasts.


Pah watches/warnings/advisories...


Short term...drs

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