Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 201058

National Weather Service Topeka KS
558 AM CDT Thu Oct 20 2016


.SHORT TERM...(Today and tonight)
Issued at 302 AM CDT Thu Oct 20 2016

07Z water vapor imagery shows an upper level shortwave moving
east across NEB and far northern KS. Forcing from this wave has
caused a band of light showers to slowly move across northern KS
this morning. Meanwhile surface obs indicate pressure rises across
central and eastern KS as the next surge of cold air moves south.

The question for this morning is when will the dry air advection win
out over the light showers. The NAM and GFS forecast soundings show
drying occurring by 12Z while the RAP keeps some saturation. As a
result, the RAP/HRRR maintain some light QPF across eastern KS into
the mid morning hours. The HRRR seems to be doing a reasonable job
with the showers so far, so have held onto some small POPs into the
mid morning hours and will monitor trends. Instability remains
pretty small and there haven`t been any lightning strikes for the
past hour. So will only mention showers or sprinkles. Eventually the
dry air and some upper level speed convergence with the upper jet
should bring an end to the precip. Although there should still be
some clouds around through the afternoon as steepening low level
lapse rates favor some diurnal CU persisting through the afternoon.
This cloud cover is expected to diminish this evening with the loss
of heating, setting up good conditions for radiational cooling as
the surface ridge axis passes across the area tonight. Have trended
the model blend temperatures for tonight a little cooler towards the
MOS consensus anticipating calm winds and mostly clear skies. This
results in a low temp forecast of mid 30s for parts of northeast and
east central KS where there could be some patchy frost for a few
hours. At this point the potential for frost appears to be limited
to low lying areas and for only a couple hours. So will hold off on
issuing an advisory. The day shift can reevaluate the need for an
advisory after looking at the 12Z information. High temps for today
are expected to be cooler than yesterday with cold air advection
occurring throughout the day. Highs are generally expected to be in
the lower 60s.

.LONG TERM...(Friday through Wednesday)
Issued at 302 AM CDT Thu Oct 20 2016

By Friday morning, northeast Kansas will be in the middle of a mid-
level trough over the eastern CONUS and a broad ridge building in
centered over the southwest US.  At the surface, high pressure will
move east throughout the day, shifting surface winds from the south.
These southerly winds will aid in a slight warm up from the previous
day, with highs expected to be near the upper 60s in central Kansas
to the mid 60s in the eastern portion of the state.  This pattern of
warming temperatures continues through the end of the weekend, with
highs Sunday in the middle 70s.  Lows also warm considerably though
this time, with temperatures near 50 seen early Monday morning.  The
next chance for precipitation begins Tuesday as a leading wave from
a building upper level trough move over the area. The GFS and
ECMWF differ slightly in the exact set up of the passing
shortwave, but for now the best timing for storms looks to be
Tuesday night through Wednesday morning. Models show up to 1000
J/kg of CAPE available through this timeframe allowing for
thunderstorm chances during this period. As for temperatures for
the first half of next week, expect mild highs in the mid 70s with
lows generally in the 50s.


.AVIATION...(For the 12Z TAFS through 12Z Friday morning)
Issued at 558 AM CDT Thu Oct 20 2016

Aside from the aggressive RAP forecast soundings, most guidance
shows VFR conditions prevailing. There are some spots with lower
CIGS but there is no confidence in restricted CIGS for any
prolonged period of time. So will keep a VFR forecast at this
time. Isolated SHRA should continue to diminish through mid




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