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000
FXUS63 KTOP 081608
AFDTOP

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TOPEKA KS
1008 AM CST Sun Dec 8 2013

.UPDATE...
Issued at 1002 AM CST SUN DEC 8 2013

Updated to add Dickinson and Ottawa counties for freezing drizzle
making for slick roadways in their areas, and also added Cloud
county to advisory for snow as light snow continues to fall there.
Considered expanding to the east along the northern row of
counties but will wait and see how precip plays out this afternoon
with wave moving out of Colorado. Soundings suggest could bring
more light snow this afternoon but reflection of lift in the
models is quite weak so will wait and see.  If northern advisory
needs an extention in time, may add some counties east at that
time.

UPDATE Issued at 550 AM CST SUN DEC 8 2013

Slightly warmer air, -10 to -8 deg C at 880MB is beginning to
advect northward into the southeast counties of the CWA. Thus some
-fzdz may begin to mix in with the snow this morning south of
I-35. The -fzdz light snow mix may continue to move northward through
the late morning and into the afternoon hours across east central
KS. At this time it should be a light mix of -fzdz and -sn. South
central KS is beginning to see accumulations of ice on roadways
due to -fzdz.

&&

.SHORT TERM...(Today and Tonight)
Issued at 356 AM CST SUN DEC 8 2013

Early this morning a positive tilt upper level trough extended from
the northern plains, southwest across the four corners region. Ahead
of the upper level trough stronger isentropic lift has developed
across north central and northeast KS, northward across the eastern
half of NE. steady light snow continued across the northern counties
of the CWA with moderate snow bands across northern Republic and
Washington counties.

The more intense and deep isentropic lift will shift northeast of
the CWA during the mid morning hours and the steady light snow
should begin to diminish across the northern counties of the CWA
during the mid and late morning hours. The positive tilt upper level
trough will fill as it shifts east across the central and southern
plains. There may be some frontogenetical forcing to continue
periods of light snow into the early afternoon hours. Forecast
soundings show the mid levels of the atmosphere drying out after 15Z
with saturated low-levels. Temperatures at the 900-850mb level will
be below -12 deg C across much of the CWA. This will allow light
snow or flurries to develop at the 900-850mb. Temperatures may warm
slight above -10 deg C at the 900-850mb level across the southeast
counties of the CWA for the super cooled liquid to perhaps fall as
patchy freezing drizzle. Though these cold temperatures may cause
the super cooled liquid to freeze into ice pellets. I kept a chance
for freezing drizzle and light snow south of the KS turnpike during
the afternoon and early evening hours.

I`ll  keep the winter weather advisory in effect for Washington and
Republic counties through the morning hours. Areas along the NE
border may have picked up 3 to 4 inches of snow from the evening
hours through early this morning based off of radar trends. The
southern sections of Republic and Washington counties may have only
received an inch or two. Farther east across Marshall, Nemaha and
Brown counties an inch up to two inches may fall through 10 AM. Most
of the CWA will only see about a dusting to an inch of snow. The
isentropic lift was not strong enough to over come the drier air at
the low-levels of the atmosphere south of I-70 but through the mid
morning hours there may be a dusting up to a half inch of snowfall
from I-70 south.

Highs Today will warm into the mid to upper 20s due to the early
morning temperatures remaining nearly steady in the upper teens to
lower 20s.

Tonight, the lingering flurries should come to an end as the upper
trough passes east into MO. Skies will clear from northwest to
southeast behind a surface cold front. Overnight lows will drop into
the single digits across north central KS with lower to mid teens
across the remainder of the CWA.

.LONG TERM...(Monday through Saturday)
Issued at 356 AM CST SUN DEC 8 2013

Will keep the daytime on Monday dry...but after a very cold
morning...clouds will linger/increase over the southern counties
with the approach of the next shortwave trough while more sunshine
occurs across the north. Although the northern counties with
snowcover will be coldest with highs in middle teens...the southern
counties will have a smaller diurnal recovery into the lower 20s due
to the clouds. With the approach and passage of the shortwave trough
to the west...have inserted a chance for snow flurries across the
far southern portions of the cwa Monday night...although the main
forcing and resultant precip chances should be south of the the
area. Winds will gradually back more to the west and southwest so
after lows of 5 to 15 Tuesday morning...should see highs recover
back into the lower 30s north to middle 30s south with sunny skies.

Another northwest flow shortwave trough will move through the area
bringing another cold front thru the cwa for Wednesday...but should
move through dry. Have cooled highs into the 20s most locations
Wednesday before rebounding back into the 30s Thursday into
Saturday...with a few lower 40s possible across the southern cwa on
Friday with persistent south winds. Will keep the cwa dry through
the end of the week as precipitation is expected to remain south of
the area.

&&

.AVIATION...(For the 12Z TAFs through 12Z Monday Morning)
Issued at 550 AM CST SUN DEC 8 2013

Periods of light snow will continue across the terminals this
morning. Stratus with VFR ceilings will gradually lower to MVFR
ceilings through the mid morning hours and remain around 1500 feet
through the afternoon. The snow may mix with -fzdz this afternoon
at KTOP and KFOE. The precip should end early this evening and
skies should clear through the late evening hours.


&&

.TOP WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY until 5 PM CST this afternoon FOR
KSZ034>040-054>056-058-059.

WINTER WEATHER ADVISORY until Noon CST today FOR KSZ008-009-020.

&&

$$

UPDATE...67
SHORT TERM...Gargan
LONG TERM...63
AVIATION...Gargan