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Area forecast discussion 
National Weather Service Paducah Kentucky
248 PM CDT sun Mar 29 2015

Short term...(this evening through wednesday)
issued at 248 PM CDT sun Mar 29 2015

Wvapor showed a short wave moving into the Great Lakes region with
a trailing front through northern Illinois into central sections
of Missouri and Oklahoma. Radar mosaic shows an increasing area
of returns ahead of the front though overall the airmass is not
that rich with moisture. Activity scattered and light at this time
and that trend should continue as the band moves northwest/southeast across the
area late this afternoon and evening. Best probability of precipitation will still be
across the southeast part of the County warning forecast area where slightly better moisture
shows up in the model output...primarily west Kentucky 01-04z.
850-750mb computed lifted indice's approach zero...but do not plan a thunder
mention just yet. Better chance of thunder should be south of US
later tonight.

High pressure will result in quiet weather Monday through Monday
night. Return flow/instability and a northwest flow shortwave...may be enough
to trigger some scattered shower/storm activity over the southeast 1/3 of
the area Tuesday afternoon and into the evening hours. We had held
off to this point...but enough data supports at least a small
chance mention. Focus then turns to Wednesday. As energy...moisture
and instability all try to push in from the west with some form of
a middle level wave. NAM seems overdone compared to the other
models...spreading convection aggressively east. This time of
year...never can be too sure. Will use a compromise approach for
now as the other models keep activity farther west through the
day. Temperatures throughout were a blend of existing numbers and the
latest MOS output.

Long term...(wednesday night through sunday)
issued at 248 PM CDT sun Mar 29 2015

Model agreement in the extended has improved somewhat over the past
24 hours...but recent model inconsistency still yields only average
forecast confidence.

Starting with Wednesday evening...a weak upper level ridge will be
positioned along the upper and middle Mississippi Valley...with weak
shortwave energy across the lower Mississippi Valley and deep south.
A cold front is forecast to be draped from low pressure just north
of Minnesota across the upper Midwest to another low pressure
center in western Kansas. Increasingly moist and unstable
southerly flow ahead of the approaching front will yield an
increasing chance of showers and thunderstorms Wednesday night and
Thursday.

Current model projections indicate the front will move into the
forecast area late Thursday afternoon...then stall somewhere in the
vicinity Thursday night. Another wave of low pressure is forecast to
develop in the Lee of The Rockies before heading east into Oklahoma
by Friday morning. This low is forecast to ride east along the quasi-
stationary frontal boundary on Friday before exiting to the east
Friday night. As a result...the potential for showers and storms
will persist Thursday night and Friday...before tapering off from
west to east Friday night.

If this particular scenario plays out as forecast...the main concern
late in the week would likely be locally heavy rain along and north
of the stalled frontal boundary. However...if the low were to move
slightly north of its projected track...then strong to severe
thunderstorms would also be a concern. Will continue to monitor and
adjust the forecast as later model guidance warrants.

Dry and cooler conditions are expected to return next weekend as
high pressure builds in. But until then...temperatures through
Friday will be quite warm. Daytime readings should average 5 to 10
degrees above normal...with nighttime readings some 10 to 15 degrees
above normal. Temperatures next weekend will be near or just below
seasonal norms.

&&

Aviation...
issued at 248 PM CDT sun Mar 29 2015

Will add showers to terminal forecast if need be. Otherwise mostly
VFR ceilings at several levels as a front moves from northwest to southeast across
the area late today and this evening. Gusty south winds will
persist through sunset...some gusts even 25-30kts. SW winds this
evening will diminish...then become light northwest overnight. Clouds
should decrease after 06z.

&&

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

$$

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