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Area forecast discussion 
National Weather Service Kansas City/Pleasant Hill MO
615 PM CDT Sat Apr 18 2015

Short term...(this evening through sunday)
issued at 447 PM CDT Sat Apr 18 2015

Thunderstorms from this morning and afternoon are generally moving
out of the area this evening. An area of some stronger convection is
still ongoing across far NC Missouri, where some residual
instability lies. The lack of any notable wind shear that far from
the mid level trough should keep the storms from being too Rowdy,
but with a few small hail reports through the day, they are
demonstrating some ability to be strong. Expect this activity to
wane through the rest of the evening as instability decreases with
time. With the large cutoff low still well off to the west the
influence of mid level ascent will generally be minimal through the
overnight hours, and this could bring a lull in the action for the
overnight hours, with perhaps some light and spotty activity ongoing
through the night. By early Sunday morning the low will finally be
more influenced by the mid level flow and eject out into the area
during the day. This will bring another round of rain across the
area. A small amount of instability will be present for this
activity, on the order of 500 to 1000 j/kg of MUCAPE, with marginal
shear, on the order of around 20 to perhaps 30 kts. All told the
severe weather potential for Sunday will be rather low, however
there could be an isolated strong storm or two. As far as timing of
precipitation is concerned, it appears that a majority of the
overnight and early morning will be dry or spotty precipitation, but
by mid to late morning the precipitation will fire back up on a more
widespread basis. This appears to be in response to the mid level
wave as it finally ejects east. Accompanying the wave will be a
surface cold front which will effectively scour out the usable
moisture, thus ending precipitation chances with its passage. For
the early to middle part of next week expect mostly dry conditions
with temperatures in the 50s to 60s, gradually warming through the
rest of the week.

Long term...(sunday night through saturday)
issued at 447 PM CDT Sat Apr 18 2015

As the middle of the upcoming week approaches, the forecast area
could see some unsettled weather once more. Convergence aloft on the
backside of an upper trough over the northern Great Lakes/Canadian
border, along with moisture to work with could allow for showers and
some thunderstorms to affect primarily the southern half of the
forecast area through the end of the week. However, model
discrepancies by late in the week through next weekend lower
confidence in the certainty of precip chances. If the European model (ecmwf) proves
to be correct, then late in this forecast period could be active as
a low skirts by the MO/Arkansas border. Conversely, while support aloft
exists according to the GFS, it depicts a surface high settling in
through the weekend despite a shortwave trough moving in and phasing
with the larger pattern.

Seasonable temps can be expected in the latter half of the week with
highs in the 60s and lows generally in the 40s. The only wrench in
the temperature forecast could be the development of a cutoff low as
opposed to an open wave traversing through late in the week (ecmwf
vs. GFS, respectively; discussed above).


Aviation...(for the 00z tafs through 00z Sunday evening)
issued at 604 PM CDT Sat Apr 18 2015

Overcast cloud layer will continue to lift north during the evening
and overnight hours with winds gradually veering ahead of a cold
front. The frontal boundary will push through Sunday morning and will
be the next player for precipitation during the latter half of the
forecast period. Some initial pre-frontal activity will commence
early Sunday morning, with a brief period of IFR ceilings possible.
The more persistent activity will occur in the mid-morning and
continue through the afternoon. Convective activity will be more
favorable to the south of the terminals, though some surrounding
thunderstorms are possible as the front pushes through the area.


Eax watches/warnings/advisories...


Short term...Leighton
long term...lg

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