Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 042354

National Weather Service Topeka KS
554 PM CST Sun Dec 4 2016

...Update to aviation forecast discussion...

.SHORT TERM...(This evening through Monday)
Issued at 318 PM CST Sun Dec 4 2016

Stratus clouds have been slow to dissipate this afternoon and were
generally from east of Emporia to Alma to Holton at 20Z. In areas
where clouds have dissipated temperatures rebounded nicely into the
mid to upper 40s. Tonight weak high pressure will move off to the
east as a low pressure trough develops in the Western High Plains
tonight. Temperatures tonight will fall into the upper 20s to lower
30s. Areas in the east will have the lightest winds and clear skies
along with wet ground. This will be offset from weak dry air
advection, however will include patchy fog after midnight across
much of northeast and east central Kansas. Further west lower
boundary layer will be mixy. On Monday as shortwave trough will move
across the Northern and Central Plains and will push a cold front
southeast into north central Kansas by late afternoon. Pressure
gradient will increase ahead of the front with winds of 15 to 20 mph
with higher gusts from late morning through the afternoon. Warm
advection and good mixing will allow temperatures to warm into the
low to mid 50s across the area.

.LONG TERM...(Monday night through Sunday)
Issued at 318 PM CST Sun Dec 4 2016

By Monday Night, a southern stream wave will be lifting northeast
with precipitation staying just south and east of the area.  The
passing of this shortwave will allow for polar air to enter into
northeast Kansas on Tuesday, with temperatures cooler than average
in the mid to upper 30s during the afternoon.  The next system to
reach the area will enter the northwest CONUS Tuesday afternoon,
swinging across to the Central Plains by late Tuesday night.  Models
have stayed relatively consistent with bringing precipitation
chances into the area by early Wednesday morning, with the best
chances late morning and into the afternoon.  Models do still differ
in QPF amounts, with the ECMWF being the most robust and the NAM
showing most higher amounts limited to central Kansas.   With such
cold air in place, all precipitation is expected to fall as snow,
and these differing QPF amounts will play a big role in how much is
actually seen.  For now, with snow ratios higher than average due to
the Arctic air, a couple inches could be seen throughout all of
northeast Kansas.

Temperatures during this time on both Wednesday and Thursday will be
very cold, with highs only expected to reach into the 20s.  With low
temperatures these nights in the teens and single digits, wind chill
values will be below zero throughout the area with some areas in
north central Kansas nearing values of -10 degrees.  Friday will be
slightly warmer, with Saturday temperatures rising back up into the
mid and upper 30s.  Once the previously mentioned system kicks off
the northeast coast early Saturday morning, relatively zonal flow
picks up over the central US.  There is a small chance for some
precipitation next weekend with a shortwave skimming near the area,
but now now will only keep slight chances due to model uncertainties
that far out.


.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
Issued at 538 PM CST Sun Dec 4 2016

There is higher than average uncertainty regarding timing and
intensity of possible vis restrictions. Believe that temperatures
will fall quickly this evening, probably leading to reduced vis by
late evening into early morning at TOP. However, expect increasing
winds to limit fog potential especially at FOE and MHK. 00Z TAF
has the most likely scenario but lighter winds could provide much
lower vis for a longer time, starting sooner and ending later.




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