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fxus63 kpah 161330 
afdpah

Area forecast discussion
National Weather Service Paducah Kentucky
830 am CDT sun Jun 16 2019

Mesoscale discussion...
issued at 830 am CDT sun Jun 16 2019

The atmosphere is much more unstable to start today vs. Yesterday.
Storm Prediction Center upgraded to a slight risk. Cannot argue too much with that,
though not sure about overall coverage. Never the less, unlike
yesterday, mlcin should more easily be overcome, with convective available potential energy well
over 3000 j/kg likely as we destabilize. Mid level lapse rates
over 7 are favorable as well. The one minor difference is lower
overall shear. Having said that, there is still a modest amount
forecast to be present. Will continue to monitor trends.

08

&&

Short term...(today through Tuesday night)
issued at 230 am CDT sun Jun 16 2019

Active convection to the north will dive south and east with time
this morning. Cams show it doing so, but on a weakening trend.
Cloud tops are still cooling now as it threatens our northern
border, will have to keep close eye upon...but will translate to
high pops, certainly across our north. Locally heavy / potentially
repeat rain will be an addition to the strong storm potential.

After sunrise, should be a relative pause, then activity refocuses
to the south and west...and again pulses east and southeast across
the area. This round will be a little further south than the pre
dawn one...so high pops will translate across the remainder of the
area this afternoon-evening. This is not altogether different than
what has been advertised for several days now...subtle areal
massages not withstanding.

Another relative pause late Sun night-early Monday, is followed by
another robust round of convection coming Monday afternoon and
evening. This may be the best pop yet, as wave opens up upon its
track across the Ozarks and mid Mississippi River valley heading
into Tuesday. Relatively speaking, pops wane, but don't altogether
disappear, later Tuesday and Tuesday night.

A marginal risk of severe exists for this time period, in
entirety, for days 1-3. As pw's continue to be modeled upward to
close to 2", or the 99th percentile, and the focusing surface
boundary orients parallel with the (mostly) zonal upper
flow...repeat locally heavy rainers may cause localized flood
issues with time.

Long term...(wednesday through saturday)
issued at 230 am CDT sun Jun 16 2019

The primary long term concern remains the potential for showers and
thunderstorms, particularly during the first half of the period. With
fair model agreement, forecast confidence starts off average, but
then decreases to below average by late week as model solutions
diverge.

The active pattern established in the short term is forecast to
persist through mid week. The next shortwave disturbance centered
over the Central Plains at 12z Wednesday is forecast to shift east
into the Ohio Valley by Wednesday night. An associated surface low
is forecast to pass by north of the region, dragging a weak front or
trough into the area on Thursday. This will provide the necessary
lift acting on a very humid and unstable air mass to result in the
potential for showers and thunderstorms Wednesday and Wednesday
night, then tapering off west to east on Thursday.

While deep layer shear is relatively low through much of the period,
the signal for increased 0-6km bulk shear southeast of the surface
low track Wednesday afternoon and evening still poses some concern
for more organized severe activity during that time. However, much
will depend on the degree of destabilization and the influence of
preexisting mesoscale boundaries from prior convection. Precipitable
water values are forecast to range from 1.5 to near 2 inches. Thus,
locally heavy rainfall could lead to localized flooding issues as
well.

Beyond Thursday, there remains a fairly consistent signal that a mid
level ridge will build into the region, resulting in a return to dry
conditions Thursday night and Friday. If the European model (ecmwf)/CMC are correct,
that dry trend may continue into at least the first part of next
weekend. However, the GFS continues to be faster at bringing the
next mid level disturbance into the region as early as Friday night.
Thus, the initialized model blend contains a chance of showers and
thunderstorms Friday night and Saturday. However, that is a low
confidence chance at this point.

Temperatures early in the period will be influenced by the amount of
sky cover and humidity, with more sunshine expected by late week. So
highs are forecast to moderate from the lower/mid 80s Wednesday and
Thursday into the upper 80s and perhaps near 90 degrees by Friday
and Saturday. Lows are forecast to moderate from the mid/upper 60s
Wednesday and Thursday nights to near 70 by late week.

&&

Aviation...
issued at 230 am CDT sun Jun 16 2019

Occasional MVFR restrictions to cigs/vsbys is possible with active
convection this morning, mainly across northern terminals. This
same potential restriction spreads further south and impacts kcgi
and kpah as well, for the afternoon hours. Otherwise visual flight
rules will prevail, even as vicinity pcpn lingers for much of the
day.

&&

Pah watches/warnings/advisories...
Illinois...none.
MO...none.

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