Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 281129

Area Forecast Discussion
National Weather Service Topeka KS
629 AM CDT Tue Mar 28 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 317 AM CDT Tue Mar 28 2017

Early this morning a mid-level low was centered near the Four
Corners region with surface low pressure advancing into western
Kansas.  Low clouds blanketed the CWA this morning, and with this
advancing low pressure, expect little to no scattering of this cloud
cover today.  The combination of overcast skies and east-
northeasterly winds will limit the amount of daytime heating that
occurs, with highs expected to be in the mid 50s to around 60

Models show the mid-level low tracking across New Mexico and
advancing toward the Oklahoma/Texas panhandles overnight into
Wednesday morning.  With this mid-level flow in place, the southerly
flow ahead of the low across the Southern Plains will support
increased moisture advection northward into the area. Short-range
models show precipitation chances increasing from southwest to
northeast across the CWA, but have slowed down the onset of the
precipitation based on the latest model runs.  As a result, expect
much of the CWA to remain dry through the day, with slight chance
PoPs entering into north central KS by late this afternoon.  Models
show precipitation chances increasing late evening through the
overnight hours into Wednesday morning with periods of moderate
rainfall likely after midnight. With the surface low lifting into
southern Kansas overnight, model soundings show some weak elevated
instability developing and spreading northward over eastern KS.  As
a result, added the mention of scattered thunder after midnight into
Wednesday morning.  These overcast skies will limit the amount of
cooling that occurs tonight with lows only expected to drop into the
mid 40s to low 50s.

.LONG TERM...(Wednesday through Monday)
Issued at 317 AM CDT Tue Mar 28 2017

Upper low will be moving out of the Rockies early Wednesday and into
the Southern Plains. Expect ongoing convection during the morning
hours as moisture is transported northward within the trowal. Lobes
of energy will rotate northward ahead of the main upper low across
eastern Kansas. Moisture transport over the 850 mb frontal boundary
over east central Kansas will lead to possible training of
convection during the morning hours, leading to runoff and rises in
the streams and creeks. The boundary will rotate northwestward
through the day on Wednesday with the heavier precipitation shifting
to across north central Kansas during the afternoon hours.

The closed upper low will gradually move eastward across Oklahoma
and Kansas exiting eastern Kansas Thursday night bringing an end
to the precipitation. Still looking at the potential for
widespread 1.50 to 2.0 inches of rain with some locations seeing
higher amounts. 40 to 55 kts of 0-6km shear along with 400 to 1000
J/kg of mucape along with increasing forcing for ascent should
support a few strong to severe storms Wednesday afternoon and
evening with east central Kansas having the highest probability.
After a brief period of dry weather from Late Thursday night
through Friday evening, the next upper trough will move out into
the Southern and Central Plains. There are differences with the
models with the speed and placement of the upper trough on Monday
owing to a lower confidence forecast. Temperatures near to
slightly above normal through the period.


.AVIATION...(For the 12Z TAFS through 12Z Wednesday morning)
Issued at 625 AM CDT Tue Mar 28 2017

For the 12z TAFs, MVFR cigs will persist today into early this
evening with east-northeasterly winds increasing by mid afternoon.
Short-range models have been trending slower with rain moving
into the terminals around midnight near KMHK and overnight for
KTOP/KFOE. This light to moderate rain will result in LIFR to IFR
cigs along with reduced vis into Wednesday morning. East-
northeasterly winds may be gusty at times overnight near 20kts.




SHORT TERM...Hennecke
AVIATION...Hennecke is the U.S. government's official web portal to all federal, state and local government web resources and services.