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National Weather Service Topeka Kansas
245 PM CDT Tue Sep 23 2014

Short term...(this evening through wednesday)
issued at 237 PM CDT Tuesday Sep 23 2014

Upper trough over the northern/Central Plains will slow its eastward
progress tonight into Wednesday while height rises
occur over The Rockies/northern plains and southeast Continental U.S..

Ongoing clusters of showers/thunderstorms will shift into the far
northeast Kansas counties by 00z this evening. Other scattered
thunderstorms may initiate late this afternoon/evening along the
Lee trough axis...from western Nebraska into western
Kansas...where surface based instability will exist. As this
activity moves east tonight...a southerly low-level jet will veer
with moisture transport/isentropic lift occurring from south
central into northeast Kansas. This will support decent chances
for showers/thunderstorms across north Central/Northeast Kansas
where elevated convective available potential energy of 500 to 1000 j/kg are prognosticated. Rain chances
will taper to 15-20% in the far southeast near Burlington and
Garnett. As the upper trough weakens Wednesday...rain chances will
gradually diminish.

South-southeasterly low-level flow in response to Lee
troughing...will keep temperatures within a few degrees of seasonal

Long term...(thursday through tuesday)
issued at 237 PM CDT Tuesday Sep 23 2014

The weakened upper level shear axis may retrograde slightly westward
Thursday into Saturday...keeping this feature over the Kansas
region. Although the shear axis will be over the
region...moisture/instability are prognosticated to lessen considerably.
Therefore...will maintain a dry forecast with mostly sunny skies and
temperatures a few degrees above average Thursday-Saturday.

Although the GFS and European model (ecmwf) differ in the details...they indicate
upper troughing pushing into the northwestern Continental U.S. Late in the
weekend into early next week...resulting in the upper ridge
getting shunted to the eastern Continental U.S.. this may result in a chance of
thunderstorms by late Monday into
moisture/instability begins to increase ahead of the upper trough.
Temperatures will be nearly a persistence forecast continuing from
the weekend.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1244 PM CDT Tuesday Sep 23 2014

Main aviation concern will be shower and storm chances through
much of the taf period.

Water vapor imagery shows a shortwave tracking over eastern
Nebraska. A broad area of isentropic lift along the 310k surface
remains over northern Kansas and will help to keep some isolated-scattered shower
and storm activity today. Severe storms are not expected. There
maybe an increase in convective coverage after 06z as a middle/upper
trough moves into the area. This will result in moisture transport
increasing in the 850mb layer. At this point confidence in
coverage is not high enough to run with a prevailing group and for
now will just use a thunderstorms in the vicinity/vcsh tonight. Cloud heights and
visibilities are expected to remain above IFR levels and likely
above MVFR levels through this taf period.



Top watches/warnings/advisories...


Short term...Caruso
long term...Caruso

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