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Area forecast discussion 
National Weather Service Topeka Kansas
1259 PM CDT Thu Sep 18 2014

..update to aviation forecast discussion...

Short term...(today and tonight)
issued at 426 am CDT Thursday Sep 18 2014

A complex weather scenario has taken place this morning ranging from
severe hail to very dense fog. The elevated thunderstorms have
developed along a mid level baroclinic zone/moisture gradient across
the southwest portions of the forecast area. Isentropic lift and
possibly a weak shortwave has been the driving force behind this
convection. Latest radar trends as well as high res models have
suggested the complex of thunderstorms will continue to drift
southeastward this morning. The NAM shows that isentropic lift will
persist through late morning over southern portions of the forecast
area. Additional isolated showers and thunderstorm are still
possible therefore have kept slight chances in those areas through
the morning hours. Instability should decrease with time but can not
completely rule out a few strong storms. It appears most of the
dense fog has improved as mid level clouds over spread the area.
This widespread fog is forecast to mix out later morning. Lingering
low level moisture trapped within the inversion in the form of low
stratus in Shawnee, Jackson, Jefferson, and Douglas counties will
also continue through late morning. Mid level clouds last most of
the day with highs in the 70s. There is another slight chance for
elevated showers and thunderstorms later tonight across far eastern
Kansas although do not expect any severe weather with these storms.

Long term...(friday through wednesday)
issued at 426 am CDT Thursday Sep 18 2014

Friday and Friday night, an upper level ridge will move east across
the plains. Expect mostly sunny skies on Friday with increasing
clouds Friday night. Highs on Friday will reach the mid to upper 80s.

The latest run of all the numerical models are now showing the
remnants of Odile remaining south of the State of Kansas across the Texas
Panhandle and into OK.

Saturday and Saturday night, an upper level trough will amplify as
it moves east across the northern and Central Plains on Saturday. A
cold front will push through the County Warning Area Saturday afternoon and evening.
Deeper Gulf moisture will be in place as the front pushes southward
across the County Warning Area Saturday afternoon. Scattered showers and
thunderstorms are expected to develop as surface convergence
increases ahead of the front and ascent increases ahead of the 500 mb
trough. The scattered showers and thunderstorms will eventually push
south of the County Warning Area as a surface ridge of high pressure builds
southward on the back side of the departing 500 mb trough. It no longer
looks as if there will be widespread heavy rainfall Saturday or
Saturday night. Though, some of the thunderstorms Saturday afternoon
and evening may produce localize brief heavy rainfall.

Sunday, there may be a few morning showers south of I-35 but skies
should clear from northwest to southeast across the County Warning Area. Highs
Sunday will be slightly cooler with highs in the upper 70s to lower

Monday through Tuesday, the center of a surface ridge of high
pressure will move southward across eastern Kansas. Highs will continue
to cool into the mid 70s.

Tuesday night and Wednesday, the broad surface ridge of high
pressure will shift east into the Ohio River valley. Southerly low
level winds will allow for deeper moisture to be advected northward
across the Central Plains. The resulting warm air advection/isentropic lift may
cause some showers and isolated thunderstorms to develop late
Tuesday night into Wednesday. The cloud cover and rain chances may
keep Wednesday cooler, with highs only reaching the lower to mid


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1259 PM CDT Thursday Sep 18 2014

IFR cigs and MVFR to continue through the majority of the forecast
period. Some improvement to VFR is expected at mhk with MVFR at
top and foe after 20z. Forecast soundings and model time sections
suggest IFR and MVFR cigs reforming after 06z with MVFR vsbys.
Ceilings improve back to MVFR after 16z at top and foe with mhk
becoming VFR.


Top watches/warnings/advisories...


Short term...Sanders
long term...gargan

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