000
FXUS63 KTOP 160448
AFDTOP

Area Forecast Discussion
National Weather Service Topeka KS
1148 PM CDT Tue May 15 2018

...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Wednesday)
Issued at 306 PM CDT Tue May 15 2018

An overall quiet night and day tomorrow are in store for northeast
Kansas with slightly above normal temperatures.

A quasi-zonal upper-level flow pattern will be present over the
region tonight into tomorrow with multiple weak perturbations
ejecting eastward from a complex low over the Great Basin. At the
surface, an expansive ridge of high pressure extended from western
Kansas to eastern Ontario and is progged to build slowly eastward
tonight and tomorrow. Given the lack of strong forcing, the chances
for any diurnally-fueled precipitation this afternoon and tomorrow
will be low and located further south towards central Kansas. Highs
on Wednesday will be similar to today, albeit a few degrees warmer
given the lesser cloud cover.

.LONG TERM...(Wednesday night through Tuesday)
Issued at 306 PM CDT Tue May 15 2018

On Thursday a mid/upper-level trough with several embedded
shortwaves will be located over the western US. By the afternoon
convection appears to initiate over the Front Range and grow upscale
over the High Plains in the late evening. A few model solutions are
suggesting this convection reaches north central KS on Friday
morning. The other possibility is additional convection develops
due to isentropic ascent within the southerly lower tropospheric
flow over portions of central KS. Towards the weekend the surface
boundary moves closer to the area as the shortwaves begin to
eject from the southwest US. The overall deep shear during this
time frame is marginal while instability remains relatively high.
It is uncertain if there will be warm sector development as subtle
shortwaves track over the region. Also, the timing of these weak
waves makes it difficult to pin down the best chances for
precipitation. The more widespread rainfall will be where the
midlevel forcing couples with the lower-level boundary, which
eventually moves southward through the area. Above normal
temperatures and relatively high lower-level moisture should allow
heat indices to approach 90 degrees ahead of the boundary. Slightly
cooler and drier air mass arrives late weekend and early next
week once the boundary is south of the area. After that the
pattern aloft becomes more zonal, so the thunderstorms chances
could increase.

&&

.AVIATION...(For the 06Z TAFS through 06Z Wednesday night)
Issued at 1148 PM CDT Tue May 15 2018

Clearing skies and light winds starting to bring visibilities down
and feel enough of this will continue for some reduction in
categories around 11Z, sooner at MHK where low cloud are more
removed. Still have minor concern for MVFR ceiling around 15Z but
confidence not high enough for inclusion. Chances for isolated
afternoon/evening convection in the area seem to be increasing and
trends will need to be watched.

&&

.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

SHORT TERM...Skow
LONG TERM...Sanders
AVIATION...65