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Area forecast discussion
National Weather Service Topeka Kansas
626 am CDT Tue Jul 16 2019

..update to aviation forecast discussion...

Short term...(today and tonight)
issued at 355 am CDT Tue Jul 16 2019

Eastern Kansas was under modest mid/upper subsidence early this
morning with the old tropical remnants in south-central Missouri.
Areas of convection to the southwest and northwest should be
entering an increasingly unfavorable environment with light to
northerly lower level flow nearer to the Missouri system. A few
observations in far eastern Kansas suggest patchy ground fog has
attempted to develop in weak winds and clear skies and continued
clear and calm conditions should support some further development
through sunrise.

Have kept today dry with infrared satellite showing generally-weakening
convection and little change in downstream conditions to support
an increase in lift. Modest west to southwest 850 mb flow brings
a warmer lower troposphere in today with temps at this level
rising around 5c from Monday afternoon. Mixing remains to be a
challenge with weak surface ridging over far eastern Kansas into
early afternoon and highs a few to several degrees warmer should
result. Heat indices rise notably and should reach to the mid 90s
to around 100 for most locations.

There is a rather consistent signal for some elevated convection
to form in northeast Kansas late tonight as modest isentropic
upglide takes place around 315k and combines with 700 mb dewpoints
around 6c for some elevated instability to develop in modest cin.
Have included small pops but any rainfall looks light.

Long term...(wednesday through monday)
issued at 355 am CDT Tue Jul 16 2019

Any overnight convection should diminish early Wednesday US upper
heights rise a bit. Stronger low-level south to southwest winds
downstream of a weak front and Lee trough lead to better mixing
and and dewpoints ticking up for the more concerning period of
heat to settle in. Convective chances associated with the
upstream boundary look small at best in very weak convergence and
700 mb temps pushing 15 c. Lower level thermodynamics change
little into the late week periods though there remains some
uncertainty in specific values. 0z gefs plumes are consistent with
850 mb temps in the mid 20s c but the operational run was a high
outlier on dewpoints. The going watch remains very prudent for the
this prolonged period of high heat and with little overnight
relief under a moderate though seasonally-strong low level jet.
There continues to be decent agreement in a pattern change later
in the weekend and will keep somewhat cooler temps for early next
week.

&&

Aviation...(for the 12z tafs through 12z Wednesday morning)
issued at 626 am CDT Tue Jul 16 2019

Ground fog visually seen at top and similar conditions are also
likely at foe. Overall setup is less likely for ground fog at mhk.
Appears MVFR stratus has stopped its southwest to westward
progress per satellite imagery but could see some brief
development at the eastern terminals over the next several hours
as mixing occurs.

&&

Top watches/warnings/advisories...
excessive heat watch from Wednesday afternoon through Saturday
evening for ksz008>012-020>024-026-034>040-054>056-058-059.

&&

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