Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 221137

Area Forecast Discussion
National Weather Service Topeka KS
537 AM CST Sun Jan 22 2017

...Update to aviation forecast discussion...

.SHORT TERM...(Today and tonight)
Issued at 334 AM CST Sun Jan 22 2017

Early this morning, water vapor imagery showed the mid-level low
spinning eastward into Oklahoma, with wrap-around moisture extending
into east central KS.  While the better forcing and moisture was
staying just south of the area near the KS/OK border, some scattered
light rain showers extended into portions of northeast to east
central KS. Short-range models show these scattered showers
persisting through the morning before exiting east of the CWA by
early afternoon.  These showers will remain in the form of rain as
the cloud cover will keep low temperatures this morning in the upper
30s to low 40s.  The next area of concern is with regards to the
potential for fog development north of these scattered showers
across northeast KS.  As of 09z, observations showed areas of dense
fog across Iowa and starting to extend into far northwest Missouri.
Short-range models continue to highlight the potential for this area
of dense fog to extend further into northeast KS early this morning
before dissipating by mid-morning.  However, one limiting factor may
be wind speeds which were already 5-8mph and are expected to
increase through the morning. Have fog mentioned in the forecast for
this morning, and will continue to monitor the trends to see if any
dense fog ends up developing across northeast KS this morning.

As the southern surface low exits east of the area today, surface
high pressure will begin to advance into the central KS.
This approaching high pressure will result in clearing skies into
central KS today but it may not extend into far eastern KS until
tonight. As a result, afternoon high temperatures will range from
the low/mid 40s to near 50 degrees from northeast to southwest
across the CWA.  With clear skies across the entire CWA tonight,
expect cooler conditions with lows plunging into the mid/upper 20s.

.LONG TERM...(Monday through Saturday)
Issued at 334 AM CST Sun Jan 22 2017

Monday remains on course to be warmer than normal with highs in
the upper 40s to lower 50s and a southerly breeze. Monday night
into Tuesday, a strong upper jet max will move into the plains
with strong sfc cyclogenesis occurring over KS. This surface low
is forecast by virtually all available model guidance to track
directly over the local forecast area on Tuesday. Winds will
become gusty in the vicinity of the low, and will probably see a
pretty good temperature gradient set up across the area with some
potential for forecast highs to change quite a bit depending on
the actual track of the low. This is a dynamic, quick-moving storm
system that appears unlikely to access quality deep moisture
locally. It also appears that the bulk of deep vertical motion
will remain north of the surface low. These two factors lead to
relatively low-end precipitation chances with better chances
farther north into Nebraska. It is worth noting that the ECMWF
remains persistent in bringing the southern edge of precipitation
down as far as I-70 while some other guidance has generally light
precip across the area as well. Current thought is that there will
be a small chance for light rain showers in the warm advection
regime immediately ahead of the low, a chance for drizzle or
light rain showers along and just behind the cold front, and then
at least a small chance for light rain/snow showers to build into
northern KS after the surface low passes. Currently any snow
should be minimal through Wednesday morning and limited to far
northern KS.

Temperatures are much cooler in the wake of this system with
persistent northwesterly flow setting up across the region. One
feature of interest is a secondary short wave trough that will
cross the area on Wednesday. There are some indications of
enhanced vertical motion associated with this feature and at least
a couple of models suggest that a band of snow may develop across
the area. Current forecast has low-end pops but will want to
monitor this time frame. Otherwise, cool and dry conditions are
expected through the remainder of the forecast period.


.AVIATION...(For the 12Z TAFS through 12Z Monday morning)
Issued at 531 AM CST Sun Jan 22 2017

For the 12z TAFs, some MVFR stratus may sink southward over the
TAF sites this morning for a few hours before shifting to the
east. Northerly winds will become a bit breezy this afternoon at
KTOP/KFOE with occasional gusts around 20kts.




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