Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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FXUS63 KEAX 271141

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
641 AM CDT WED JUL 27 2016

Issued at 339 AM CDT WED JUL 27 2016

Primary concern in the very near term will be the decaying MCS and
associated cloud cover dropping southeast toward the forecast area
this morning. Although the storms are quickly losing support from a
lagging upper trough and LLJ; fairly robust outflow and a thick
cloud shield has already progressed well ahead of the storms, and
may brush the northwestern forecast area later this morning. A
capping inversion and any increased stability from morning cloud
cover should keep the outflow boundary from initiating storms this
morning, but have increased cloud cover and slowed temperature rises
a bit mainly from STJ northward for the majority of the morning.

Still expecting a chance for widely scattered thunderstorms late
this evening through tonight as the shortwave trough drops southeast
across the forecast area. Weak high pressure in place ahead of the
front will suppress much convergence along this trough`s associated
surface cold front, and timing of the frontal passage will also be
unsupportive of surface-based convective initiation, but upper-level
forcing should be enough to encourage elevated convection to develop
after sunset. Have left PoPs generally around 40 percent to account
for the anticipated scattered coverage, and have struggled to really
pinpoint any area with a better probability for storms versus any
other due to the breadth of the forcing.

Precipitation chances generally decrease on Thursday, but was not
comfortable lowering PoPs much below 30 percent with a weak cap in
place an a few subtle perturbations in the upper-level flow. A few
models indicate that scattered convection associated with shortwave
energy east of the forecast area could build westward with time
during the afternoon hours, but it`s likely that the majority of the
area and the majority of the daylight hours will be dry. By late
Thursday night, another shortwave trough will fire up a complex of
thunderstorms across central NE and possibly into northeast KS,
which will then propagate southeast as the trough carves a southeast
to eventually more easterly path across the central Plains Friday
AM. The timing is again not ideal for precipitation in the CWA, and
models differ with how far south the shortwave trough makes it
before turning more easterly, so have kept PoPs below 40 percent for
the possibility that storms could miss the CWA to the west. However,
could easily see our Friday morning PoPs increasing quite a bit if
model agreement improves, since the complex to our northeast should
be fairly robust and the similar movement of the upper trough would
help support continued convection throughout the morning hours

Temperatures today will be a shade warmer than yesterday as warmer
850 hPa temps build east and mixing heights increase, then a slight
cooling trend is expected for Thursday and Friday as the shortwave
trough helps pull cooler air aloft into the region from northeast to
southwest. The cooling trend will end and eventually reverse this
weekend when northwest flow flattens a bit, and weak, broad upper-
level ridging gradually returns next week. On-and-off storm chances
continue through the weekend without any discernible feature on
which to focus a period of higher PoPs; however, with ample
instability and zonal flow aloft, any little blip of a shortwave
trough could spark convection, and will need to hammer out those
details at a later time.


.Aviation...(For the 12Z TAFS through 12Z Thursday Morning)
Issued at 641 AM CDT WED JUL 27 2016

VFR conditions are expected to persist through the TAF period. Winds
will be light and variable in direction throughout the day, becoming
nearly calm overnight tonight but maintaining more of an easterly
direction after 06z Thursday. A few passing high clouds are expected
this morning, then some cumulus may develop this afternoon but should
remain scattered, and with bases above 5 kft.


.EAX Watches/Warnings/Advisories...


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