Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 130830

Area Forecast Discussion
National Weather Service Topeka KS
330 AM CDT Sun Aug 13 2017

.SHORT TERM...(Today and tonight)
Issued at 329 AM CDT Sun Aug 13 2017

Early this morning showers with embedded thunder were ongoing across
north central Kansas and had moved into western parts of Republic
county. Loop of the regional radar suggests there may be a weak mcv
over south central Nebraska. Further south convection was ongoing
across north Texas along the Red River with the southern stream wave
while scattered convection was occurring over southwest Kansas. The
low level jet was focused across western into central Kansas at 08Z
and has focused the deeper moisture there. Across northeast and east
central Kansas the surface high expected from northeastward into
Wisconsin. Moisture was beginning to increase from the south into
east central Kansas with low cloud deck moving into the Emporia area
since 06Z.

For today the latest CAMS runs as well as the NAM continue to
weaken the showers over north central Kansas through 12Z this
morning with only the HRRR holding onto isolated showers through mod
morning. Showers should continue to weaken as they move east and
encounter an environment with weak lapse rates and drier air and
convection over eastern Nebraska moves east into Iowa ahead of a mid
level wave. Highs today will reach the low to mid 80s with a mix of
sun and clouds.

Tonight, another wave will move out of Wyoming and across Nebraska
and into north central Kansas after 06Z. While a frontal boundary is
expected to extend from a low over northeast Nebraska to northeast
Colorado by 12Z Monday. Isolated convection may affect parts of
north central Kansas after 06Z Monday and have left small
precipitation chances going there. Meanwhile low level moisture
should increase across northeast and east central Kansas as the
surface high slides off to the east allowing for southerly flow.
Could see an area of lower clouds spreading northward after
midnight. Lows tonight are expected to the be in the mid 60s.

.LONG TERM...(Monday through Saturday)
Issued at 329 AM CDT Sun Aug 13 2017

By Monday morning, a subtle weak mid-level ridge will be in place
over the central U.S. with the exiting trough moving northeast of
the Great Lakes region and the next mid-level trough diving
southeastward into the Pacific Northwest.  This weak ridge will
quickly break down over the central U.S. Monday into Tuesday as the
mid-level trough continues to dive deeper across the Rockies, with
several weak disturbances within the southeastern edge of the trough
tracking into Kansas.  At this time, much of the associated
precipitation should stay further west and south of the CWA Monday
and Monday night, but cannot rule out a slight chance for
precipitation to clip portions of north central KS Monday morning.
As the mid-level trough axis begins to pivot eastward toward the
central U.S. Tuesday into Wednesday, it will help to push surface
low pressure over Colorado eastward into Kansas. Models show an
associated warm front lifting northward across the CWA on Tuesday,
bringing additional chances for scattered showers and thunderstorms.
 Precipitation chances increase Wednesday into Wednesday night as
the advancing area of surface low pressure pushes a cold front into
the region.  There are still subtle timing differences amongst the
models, but in general the front looks to move into north central KS
Wednesday morning and will slowly track southeastward across the CWA
through the day before finally exiting Wednesday evening. These
Wednesday afternoon/evening storms will have the potential to become
strong to severe across northeast and east central KS as model
soundings at this time show the cap eroding during the afternoon,
with modest CAPE and deep-layer shear in place.  Also, with PWATs
near 2 inches, some locally heavy rainfall will also be possible
with these storms.  Precipitation will end from west to east
overnight Wednesday night with dry conditions into Thursday morning
before the next disturbance moves into the area.  As the mid-level
trough axis tracks eastward across the central U.S., a few weak
embedded waves within the mid-level flow may skim across the CWA
late Thursday through Saturday, bringing additional periodic chances
for scattered showers and storms.

Despite the frontal passage mid-week, temperatures look to remain
fairly persistent through this upcoming week with highs in the
mid/upper 80s and lows generally in the mid/upper 60s.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1108 PM CDT Sat Aug 12 2017

Not much change in forecast thinking. High clouds should preclude
any ground fog. And high resolution models continue to show the
precip across NEB falling apart before reaching the terminals. So
VFR conditions are forecast to persist.




LONG TERM...Hennecke
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