Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 271713 AAA

National Weather Service Topeka KS
1213 PM CDT WED APR 27 2016

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 336 AM CDT WED APR 27 2016

The center of the upper level storm system that brought widespread
severe weather and heavy rain to the region late Tuesday continues
to spin over north central KS. The large precipitation shield has
pushed east of the area but scattered showers remain possible
through the morning as ample moisture continues to pump into the
upper system with strong forcing for ascent. Instability through
the morning will remain on the low end with cooler temperatures
and surface dewpoints now in place but very cold temperatures
aloft will support a return of instability to far eastern Kansas
in advance of a westerly wind shift. By noon, expect this boundary
to be roughly along HWY 75 and should push to near the KS/MO
border by 3 PM. 1000-1500 J/kg of SBCAPE should exist east of the
front. Expect scattered convective development along this front
during that time frame. Effective shear may be marginally
supportive of supercell structures, particularly given the very
steep mid level lapse rates and a good amount of low level CAPE.
This presents favorable stretching parameters off the surface but
low level shear profiles currently appear weak. This suggests that
a few low-topped supercells may develop which would mainly favor a
small chance for severe hail to develop in far eastern counties of
the forecast area...and slightly better chances with northward
extent closer to the upper low center.

Farther west, expect a persistent area of showers and perhaps a
thunderstorm on the west and southwest side of the upper
low...mainly impacting north central KS. This will keep
temperatures cooler in this area as well, with highs ranging from
the upper 50s in Republic county KS to the lower 70s in Anderson
county. A few showers may linger in northern KS through the
evening as the upper low slowly migrates east but otherwise expect
a drying trend. Throughout the period do not expect much total
additional rainfall so impact on ongoing flooding should be

.LONG TERM...(Thursday through Tuesday)
Issued at 336 AM CDT WED APR 27 2016

Thursday will be dry but the next slow moving upper level trough
will begin to impact the area by Friday morning as there is strong
model agreement in a lead impulse ejecting across the Plains with
widespread showers and perhaps a few thunderstorms. Instability is
forecast to be quite weak through Friday night. The main trough
energy is forecast to move across the region on Saturday though
and should bring with it much steeper lapse rates aloft. This may
support better instability but with so much widespread precip
likely in advance of the system, it seems that there should be
plenty of overturning to limit the overall severe threat.
Regardless, there is at least some potential for a round of severe
storms with the main wave on Saturday...with the intensity of
those storms conditional upon the development of a good amount of
instability to accompany moderate deep layer shear. Yet another
upper level trough comes across the area for the first part of
next week with additional rain chances before an upper ridge
finally looks to build over the region for a few days by mid-week.

High temperatures through the mid/long term look pretty stable,
generally in the 60s to low 70s, and somewhat depending on cloud
cover and widespread nature of rain. Lows will be mainly in the
40s to low 50s, also dependent upon cloud cover.


.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1201 PM CDT WED APR 27 2016

The Pacific cold front will be moving through the Topeka area
around 18Z causing winds to veer at TOP/FOE with CIGS expected to
be near 030-035 through the afternoon. Will be optimistic on CIGS
and keep them VFR given continued mixing and drier air moving in. There
is some scattered -shra developing in wake of the cold front as
the upper system spins across Nebraska so will keep mention
through the day with VFR expected after 00Z.


.TOP Watches/Warnings/Advisories...


SHORT TERM...Barjenbruch
LONG TERM...Barjenbruch
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