Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 281135

National Weather Service Topeka KS
535 AM CST SAT NOV 28 2015

...Update to aviation forecast discussion...

.SHORT TERM...(Today and Tonight)
Issued at 341 AM CST SAT NOV 28 2015

At 3 AM, a band of moderate precipitation had developed and extended
roughly from Morris county to the east northeast and also back to
the west southwest. Reports from Council Grove confirm that this
precipitation is all freezing rain except for the northwest fringe
where some sleet was mixing in. Reports also confirmed that very
slick conditions had developed underneath the rain band. This
appears to be in response to a compact embedded vorticity maximum
and will continue to develop slowly east and east northeast through
sunrise or shortly thereafter. Rainfall rates of 0.05"-0.10" per
hour are likely under the heart of the band, and some areas could
pick up a quick 0.1" to 0.2" of ice accumulation early this morning.

The weather for the remainder of the day and into tonight will be
quite similar to what has been happening over the past 24 hours as
the upper level storm system and associated upper jet and moisture
feed have been essentially stationary and will move very little in
the short term. The timing of more organized periods of
precipitation and drying will be closely tied to very small embedded
short waves. One of these will move impact the area through sunrise
or shortly thereafter while another will impact the area during the
afternoon hours, and another is possible by late evening or early
morning. Even during the "drier" periods of subsidence, drizzle will
be possible. So with the continued periods of precipitation, the
question turns to precipitation type. This morning, freezing rain
and freezing drizzle will be the main precip types although any
precip north of an Abilene to Holton line will have a good chance of
mixing with sleet and from Concordia to Marysville north will be
mainly sleet. The warm nose conditions will not change much through
the afternoon into tonight, but surface temperatures appear likely
to rise at least slightly with the freezing line likely retreating
northwest this afternoon into tonight. Current best estimate is that
the freezing line will at least come close to the Emporia to Topeka
line by late afternoon, and hold nearly steady or drift back
slightly east overnight. Even where temps are above freezing, they
will likely be less than 34 degrees. The heaviest precipitation
amounts through the period are likely to be generally near and
southeast of that Emporia to Topeka line, so just how much the
temperature warms will have a huge affect on the overall impacts of
this weather. For now have continued the winter weather advisory for
much of the area through 6 PM and will continue to evaluate through
the day as the main questions regarding this product will be
location of the freezing line and whether any more widespread precip
can develop into north central KS outside of the advisory area.

For now, the take-away message is to expect continued very hazardous
travel conditions, especially in association with the bands of more
organized precipitation. The whole area should plan for these
conditions to continue through tonight, although with at least some
potential for melting to take place in parts of eastern Kansas this
afternoon into tonight.

.LONG TERM...(Sunday through Friday)
Issued at 341 AM CST SAT NOV 28 2015

By Sunday morning, warm air advection continues to enhance lift
along a 850 mb boundary across northeast Kansas, while very weak
embedded waves within the southwest flow aloft generate areas of
light precip on Sunday. Shallow cool air advection at the sfc begins
to wane allowing temps to reach above freezing in the afternoon
hours, with the exception of far north central Kansas. Gradual loss
of saturation in the ice growth layer creates a wintry mix of precip
from freezing rain or freezing drizzle in the morning to simply
rain/drizzle over east central Kansas where highs are in the upper
30s. Further west, soundings appear to hover temps closer to
freezing at the sfc, resulting in freezing drizzle to continue
through the afternoon.

Late Sunday evening into Monday is the main period of concern in the
forecast as a strong embedded trough is ingested in the weakening
upper low before swinging northeast towards the central plains.
Trends from latest runs of guidance shows the incoming wave further
south, enhancing the available lift and amount of qpf across the
area. The higher qpf with temps hovering near freezing will result
in a higher potential for accumulating frozen precip. With the
colder temps in the h85 layer over north central KS, believe precip
type could contain more of a snow and sleet mix, while further south
the warm nose is near 5C with a mix of sleet, freezing rain and rain
likely through Monday. Accumulations of ice are generally light and
less than a tenth of an inch. Snow accumulations between 1 and 3
inches are possible for areas in north central KS, close to the NE
border through Monday. These numbers may easily change so it
important to stay up to date on the latest forecast.

Precip exits northeast by Monday evening with clear skies and
seasonable temps returning to the area. Expansive ridge will build
across the region as temps recover into the 40s and 50s through the


.AVIATION...(For the 12Z TAFS through 12Z Sunday Morning)
Issued at 529 AM CST SAT NOV 28 2015

Freezing rain is ongoing at TAF sites at 12Z with some sleet
mixing in at MHK. Periods of freezing rain or freezing drizzle are
expected through the day with the best chances in the next two
hours, and again between 18Z and 00Z. Temperature will rise
slightly and may rise above freezing by late in the day. Cigs will
mainly be in the 700 to 1200 foot range with TOP/MHK likely to be
predominant MVFR while FOE is likely to hold in IFR category.


.TOP Watches/Warnings/Advisories...
Winter Weather Advisory until 6 PM CST this evening for



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