Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 141121

Area Forecast Discussion
National Weather Service Topeka KS
621 AM CDT Sat Oct 14 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 322 AM CDT Sat Oct 14 2017

Active weather pattern over the next 24 hours. Early Saturday
morning the area remains bisected by a warm front that extends out of
southwestern KS and northeastward through northeastern MO.  Flow
aloft is southwesterly as well, with impulses noted in the flow from
central Kansas southwestward into southern NM.  These impulses are
forecast to move northeastward over the front through the day today,
before the larger scale upper trof moves off the central Rockies and
drives a coldfront through the forecast area this evening and
overnight.  Initially the smaller features will bring showers and
embedded thunderstorms through the morning hours, some of which may
mix down some gusty winds as they pass overhead with soundings
indicating a layer of 40kt winds not far off the surface.  These
storms are not expected to bring severe storms early on however. As
the upper trof approaches and area undergoes some resultant cooling
in the mid levels, the increase in instability and continued strong
winds in the column will make strong to severe storms possible along
the front as it moves through generally in the 4pm to midnight
window. In addition, strong winds sweep in behind the front, with a
period of sustained winds in the 30s with gusts in the 40s this
evening - with some soundings in our western counties also showing
peak wind gusts near 50 at the top of the boundary layer.
Temperatures across the area run from the 60s northwest today to the
80s in our southeast, and well mixed lows tonight in the colder air
will run in the 40s but likely feel slightly colder.

.LONG TERM...(Sunday through Friday)
Issued at 322 AM CDT Sat Oct 14 2017

On Sunday the mid level shortwave trough lifts over the Great Lakes
region allowing northwest flow aloft. This will support a surface
high pressure to slide through the central and southern plains.
During the morning this surface high will be centered in the high
plains, which keeps the pressure gradient across eastern KS until
later in the day. Lows around sunrise are forecasted to be in the
40s with wind gusts around 20 mph, so wind chills may drop into the
30s for a brief period. Winds will decrease through out the day and
highs reach the lower 60s with mostly sunny skies. The high pressure
slides just south of the area on Monday ushering in return flow and
allowing the highs to reach the upper 60s and lower 60s. Northwest
flow aloft continues through late week, which will keep the weather
quiet and temperatures seasonable. On the weekend a strong mid-level
shortwave passes over the Rockies. There is considerable model
disagreement as to the strength and evolution of a piece of energy
that gets cut off from the main flow. Another shortwave in the
northern stream over Canada pushes a cold front towards the region
therefore increasing the rain chances over the weekend.


.AVIATION...(For the 12Z TAFS through 12Z Sunday morning)
Issued at 555 AM CDT Sat Oct 14 2017

Impacts on terminals today will be showers and storms this morning
into the evening, then strong winds behind the front later
tonight. Prevailing showers VCTS continue for early in the period
with winds from the south, shifting to the west later in the
afternoon. Another area of storms forecast for the evening hours
before clearing quickly from the west.




LONG TERM...Sanders
AVIATION...67 is the U.S. government's official web portal to all federal, state and local government web resources and services.