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Area forecast discussion 
National Weather Service Kansas City/Pleasant Hill MO
624 PM CDT Sat Jul 12 2014

issued at 340 PM CDT Sat Jul 12 2014

Hot and muggy conditions continue across the forecast area as good
insolation, southwest surface flow, and moist boundary layer conditions
are contributing to heat indices approaching 100 degrees. Expect a
few more degrees of heating today, as temps should approach the 90
to 95 degree mark, with dew points remaining in the lower 70s. The
result will be a few hours this afternoon/evening of heat indices in
the 100 to 103 range. North of the forecast area, in central Iowa, a
surface boundary resides, characterized by the aforementioned
90s/70s south of the boundary with temps in the 60s to 70s north of
the boundary. This boundary will be the focus for afternoon
convection, mainly north of the forecast area. This boundary will
soon take on the form of a cold front and sag southward through the
evening hours. Areas of far northern Missouri will have the best
chance to see these evening thunderstorms before sunset. As the
boundary sags farther south it will continue to generate
precipitation, aided by mid level pressure height falls associated
with the upper trough. However, as the boundary approaches the
Interstate 70 corridor it will likely lose quite a bit of heating,
which will mitigate the widespread thunderstorm threat. Given the
cooling surface conditions and a fairly warm and dry 800-900 mb
layer it will be tough to get showers and thunderstorms to form
along the I-70 corridor during the overnight hours. That being said,
there is a chance that a few scattered showers could form tonight,
and have advertised pops accordingly. But the best chance for
thunderstorm activity will definitely be north of I-70. Models then
hint at the boundary re-firing as it continues to sag south of the
forecast area, perhaps bringing a chance for some rain early Sunday
morning across areas south of I-70.

A fairly significant pattern change is then in store for the first
half of the upcoming work week. While the initial Saturday/Sunday
boundary will bring some cooler/drier air to the area, another shot
of cool/dry air will push into the area as a strong surface ridge
builds into the northern plains for the early part of next week.
There could be another shot at some light rain on Monday as some
forcing in the form of a mid level shortwave trough and stronger low
level ascent moves through, but these showers will be progressive so
precip amounts will be on the low side. Monday will begin the
cooling trend, as highs will likely remain in the upper 70s to lower
80s, then on Tuesday temperatures will likely remain in the lower to
middle 70s. While the surface ridge remains in place over the c/North
Plains conditions will remain well below normal for July.
Temperatures will begin to recover and become more seasonal by the
end of next week, as the surface ridge moves to the east, allowing for
southerly flow to recommence. By Thursday highs will be creeping
back near the 80 degree range, and by the end of the week, and into
the weekend temps will have come back up into the 80s.


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 624 PM CDT Sat Jul 12 2014

Isolated thunderstorms will continue to develop across far northern
Missouri this evening, but should stay mainly north of the terminals.
A second round of convection will develop along a southeastward
moving cold front later this evening, and may impact stj slightly
after 06z. Storms may not hold together long enough to impact mci and
mkc, but the wind shift should move through around 09z-10z. Scattered
MVFR ceilings are possible just behind the boundary, but should mix
out quickly on Sunday morning.


Eax watches/warnings/advisories...



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