Area Forecast Discussion
Issued by NWS Topeka, KS

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FXUS63 KTOP 012341

541 PM CST Sun Feb 1 2015

Issued at 508 PM CST SUN FEB 1 2015

Extended the winter weather advisory mainly for blowing snow
reducing visibilities until 9 PM. Do not expect more than a
dusting of additional snow through 9 PM.


...Update to aviation forecast discussion...

.SHORT TERM...(This Evening through Monday)
Issued at 240 PM CST SUN FEB 1 2015

Strong cold front continues to push southward across the forecast
area today. With it has come periods of light snow and windy
conditions, which along with the incoming cold air has brought
blowing snow, slick spots on roadways, and reduced visibilities in
blowing snow for some of our northern and western counties.  Will
continue to carry snow for the afternoon and areas of blowing snow
for the remainder of the afternoon, as winds are not expected to
decrease by a substantial amount until after midnight.  Snow is
lightening up as of middle afternoon, and as the upper trof axis is
now overhead and pushing eastward, expect snow to continue to
lighten and come to an end over the next several hours. Will keep
winter weather advisory in place through 6pm.  Roads will likely
stay slick through the overnight hours as temperatures continue to
fall, even though the snow comes to an end.

Overnight concerns will initially be blowing snow, but as the wind
and actual snowfall diminish, think this will become less impactful
through the evening.  However incoming cold air mass is quite cold,
and will drop overnight lows down into the single digits south and
to a few degrees below zero in our north.  This will bring
widespread wind chill values in the negative single digits, and may
come close in the far north to -15 by sunrise on Monday.  Will
monitor conditions, as if temperatures are even a few degrees cooler
than forecast, may need a Wind Chill advisory for the northern
counties around sunrise. Forecast highs on Monday are 20s far
northeast to around freezing in the west, although should at least
see some sunshine for a while during the morning and early

.LONG TERM...(Monday Night through Sunday)
Issued at 240 PM CST SUN FEB 1 2015

Weak ridge shifts across the Central Plains Monday evening and
Tuesday as lows Tuesday morning recover back into the teens and
lower 20s. Southwesterly winds at 850 MB Tuesday afternoon increase
to near 20 kts over north central Kansas. Decent mixing on the
eastern edge of the ridge where temps rise to 6C results in highs
quickly rising to the low and mid 50s over central Kansas. Since
guidance is not ingesting the amount of snow cover at this time,
there is more uncertainty in highs further north. Have trended down
using raw guidance where upper 30s/lower 40s seemed more plausible.
Next upper trough to watch arrives into northeast Kansas Wednesday
afternoon and evening. All guidance is beginning to come together
with previous versions of the ECMWF where a decent baroclinic zone
sets up right behind the frontal boundary. Highs Wednesday in the
20s to low 30s will keep all precip in the form of light snow. The
progressive nature of the wave suggests little to no accumulations
as it exits Thursday morning. A very cold arctic airmass settles
overhead at this time as low temperatures range from the single
digits to 5 degrees below zero. Any snow cover could have an effect
on these temps being a bit cooler.

Dry northwest flow resumes for next weekend as southerly flow
towards the sfc increases warmer air mixing to the surface. Highs
quickly recover back into the 40s and 50s as overnight lows average
in the 20s and 30s. Another upper trough rounds the western ridge
and tracks southeast through the Midwest Saturday evening into
Sunday. With most guidance showing better forcing staying to the
northeast, have removed precipitation chances at this time.


.AVIATION...(For the 00Z TAFs through 00Z Monday Evening)
Issued at 541 PM CST SUN FEB 1 2015

MVFR cigs and vsbys with occastional IFR vsbys will continue with
SN and BLSN through 02Z with improving vsbys to VFR. Cigs are
expected to improve to VFR in the 06Z-09Z time period. Winds will
continue around 22kts with gusts to 33kts through 02Z then
decreasing through 06Z with winds below 10 kts after 09Z.





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