Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 282323

National Weather Service Topeka KS
523 PM CST SAT NOV 28 2015

...Update to aviation forecast discussion...

.SHORT TERM...(This Evening through Sunday)
Issued at 307 PM CST SAT NOV 28 2015

Scattered to widespread freezing rain has developed and spread
across the area today as shortwave energy translates through the mid
level flow. Soundings show the temperature profile has a warm nose
that remains above temperatures needed to fully melt any snow
falling into that layer. While the low level cold air has begun to
modify therefore no longer supporting the potential for refreezing
into sleet. Also, any lift within the warm nose could generate rain,
which will fall into the freezing air. The models have overestimated
the modification of the surface freezing line, and in actuality most
places have remained below freezing. This trend will continue into
the overnight. Models indicate that this current round of freezing
rain will last through the evening hours. Any accumulations this
afternoon and early evening will be light, but enough to cause
travel issues.

After that the models begin to lose saturation in the cloud
therefore leading to more freezing drizzle with any low level lift
still present. Models show another weak shortwave will lift over the
area early tomorrow morning through the afternoon very similar to
the scenario currently unfolding. Again most locations stay under
freezing through sunrise and so freezing rain is the likely precip
type. Because of this, have extended the winter weather advisory
through tonight. Later in the morning there is model agreement
that the freezing air moves to the northwest over a significant
distance. In that case the only area to stay below freezing all
day would be far north central KS, but those locations have the
smallest chances of measurable precip. The better chances for
freezing rain during this period appears to be central into east
central KS. Any lingering showers tomorrow should change over to
rain or drizzle. Again, any amounts of ice will be light, but will
impact the travel until surface temps warm above freezing. Have
extended the winter weather advisory until 6 am for this potential

.LONG TERM...(Sunday Night through Saturday)
Issued at 307 PM CST SAT NOV 28 2015

Models continue to show better dynamics lifting across the region
Sunday night and Monday. The overall trend of the system has been
to shift the heavier precip to the east where the deeper moisture
should set up. The greatest uncertainty is the thermal profile
and resulting precip type. The GFS is deeper with a surface low
that develops Monday morning to the southwest of the forecast
area. As a result, the GFS is much stronger and more persistent
with low level warm air advection into eastern KS on Monday.
Meanwhile the other guidance appears to be less aggressive with
the low level warm air advection keeping temps around or just
below freezing Sunday night over north central KS and a good
portion of northeast KS. Because of this, have not changed from
the previous forecast for a renewal of a wintry mix Sunday night
and through the morning Monday. Far eastern KS still looks to be
just above freezing so that most if not all the precip will be
rain. Because of the uncertainty in the thermal profile and the
fact that the forecast is right around freezing, there is a good
chance that the details of precip type and amounts could need
adjustments in later forecasts. At this point thinking mixed
precip is probable, have not gone crazy with amounts and have new
ice accumulations around a tenth of an inch across north central
and northeast KS with 1 to 2 inches of snow possible around the
Concordia, Washington and Belleville areas. Because of the current
advisory in effect, opted to not issue one for Sunday night and
Monday to reduce any confusion. However based on the forecast, an
advisory may be needed at some point.

By Monday evening, the dynamics are progged to be lifting to the
north of the forecast area with a Pacific cold front sweeping in
dryer air from the west. This should mark the end of the prolonged
winter precipitation. The closed upper low slowly moves towards
the Great Lakes while a shortwave rotates over the central plains.
Tuesday night. This is not expected to amount to much due to the
dryer air in place. For Wednesday through Saturday, general
ridging is progged over the central plains with temps moderating.
The stronger southerly low level flow and warm air advection
appears to develop by Friday and into Saturday. This is where the
forecast has the warmer temps with highs in the 50s for most
areas. The forecast has cooler temps near the Neb state line
through the work week anticipating the possibility for some snow
cover from Monday morning.


.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 520 PM CST SAT NOV 28 2015

IFR conditions are expected to continue through Sunday afternoon.
Periods of freezing rain will continue into Sunday at MHK. Light
freezing drizzle will transition to light rain on Sunday at
TOP/FOE as surface temperatures are expected to hover just above


.TOP Watches/Warnings/Advisories...
Winter Weather Advisory until 6 AM CST Sunday for KSZ010>012-



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