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

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FXUS63 KEAX 032339

639 PM CDT MON AUG 3 2015

Issued at 418 PM CDT MON AUG 3 2015

Fairly active pattern continues for the lower Missouri River Valley
through the middle and later part of this week. For the rest of
today a fairly potent outflow boundary has moved across portions of
the KC Metro area, with all areas north and east of KC in the lower
to middle 80s, and areas west and south of KC in the lower 90s. The
remnants of this morning`s convection has dwindled to a couple
showers in northwest Missouri. As the day progresses there is a
slight chance of some afternoon showers, with perhaps the better
chances for rain along and west/south of the aforementioned
boundary, that resides in the KC metro area and extends toward the
NW and SE. Visible imagery suggests some CU along and south of the
boundary, which could be the better sign for convective development,
but forecast soundings in the area indicate a rather stout cap. So,
it`ll likely come down to a well timed embedded shortwave trough
within the ambient NW flow aloft to kick something off. At this
point, short-range convective models, which have not done a
tremendous job of predicting convection have the area dry. Despite
this generally dry forecast within the HRRR, will keep some slight
chance PoPs going through the afternoon, again, generally along and
south/west of the outflow. By tonight, around midnight there is at
least some hint with the NAM that a very subtle wave could roll
through the area. This wave could kick off a few showers and
thunderstorms across northern Missouri, most likely along and north
of Interstate 70, although cold pool formation and organization
could allow these storms to push a little farther south, toward I-
70, or possible parts south of I-70.

The active period continues through the day on Tuesday. A surface
trough forms ahead of a fairly potent mid level trough Tuesday into
Tuesday night. This low level trough will be rather classic in
nature, with a advance of moisture northward and back surface flow
ahead of the trough. Behind the low level cyclone, a closed off mid
level wave then moves into the area by Tuesday night, which will
offer abundant mid level support for ascent. This will kick off
several rounds of widespread rain across the area. Forecast models
have been a bit inconsistent regarding the track of this wave, but
latest runs of GFS and NAM indicate a more southerly track of this
wave, which would put areas along and south of I-70 in the
crosshairs of moderate to heavy rain. Should the trend to the south
continue it`s possible this system will be more likely to impact
southern and central Missouri, across the I-44 corridor. Wherever
this wave tracks will likely see several inches of rain through the
overnight hours Tuesday night and through Sunday. Further
complicating matters is the potential for severe weather ahead of
the system. As mentioned earlier, there will be a pretty classic low
level cyclone with this system, which will create a strongly veering-
with-height wind profile, causing clockwise, curved, and long
hodographs. For now it appears the wave will be coming through the
area at minimum heating, which would diminish the severe threat, but
should the wave slow down much and allow surface heating before
moving through there could be some severe weather with this system.
Again, with models being so inconsistent with placement and timing
there isn`t much confidence going into the specific evolution, but
overall it appears to be rather wet and possibly severe somewhere
across southern and central Missouri on Wednesday.

For the later part of the week, the only real synoptically evident
signal is the mid level ridge sliding toward the desert southwest,
which will create some decent mid level flow over the area. This
will keep the chances for rain alive through the middle to later
part of the week, as various complexes form across the Northern and
Central Plains and glide through the forecast area.


.AVIATION...(For the 00Z TAFS through 00Z Tuesday Evening)
Issued at 631 PM CDT MON AUG 3 2015

The evening hours should remain dry as an outflow boundary from
earlier convection to the east has since pushed to the west of Kansas
City. However, overnight convection is expected as a subtle wave may
trigger activity surrounding the terminal sites. The models have not
handled convection well as of late, so may need to fine tune the
timing of convection through the evening hours. Stronger forcing will
present additional thunderstorm development beginning Tuesday
afternoon and will likely persist beyond the end of the forecast




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