Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

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FXUS63 KEAX 241753

1153 AM CST Wed Dec 24 2014

Issued at 356 AM CST WED DEC 24 2014

Regional radars showing an elongated area of light returns extending
from central IA south through east-central KS. Activity is occurring
along the western edge of an elongated shear axis associated with a
an upper trough that continues to inch eastward across the Nation/s
midsection this morning. So far...activity has been very light as noted
by the current viability of 7SM at KCI...which has reported snow for
the past few hrs. Not that this is at all surprising as models in
recent days have advertised a high POP/low QPF type scenario which
is still expected to yield little snow accumulation across the fcst
region. Quick look at EAX correlation coefficient dual-pol radar product
now snowing RA/SN line working south of the KC metro which correlates
well with recent obs across the area.

Current activity expected to gradually start working east through the
morning and early afternoon hrs. Precip type does remain a little
tricky with temps largely residing in the lower to middle 30s across
the area. Temps this morning should begin warming which should result
in a gradual change over back to a RA/SN mix...and possibly all rain
later today across eastern sections of the CWA. Regardless...ongoing
and expected precip later today should have little if any impact to
holiday travel. When all is said and done...cannot rule out a half
inch of snow on grassy surfaces but in reality...this may be a little
on the generous side.

Precip should be long gone by this evening which will set the stage
for building heights and developing warm air advection as long wave
trough digs into the Intermountain West. As this occurs...persistent
northwest flow aloft will quickly back to the  southwest as heights
build downstream across the Heartland. This will lead to an
absolutely gorgeous Christmas holiday as temperatures warm into the
upper 40s to lower 50s under mostly sunny skies overhead. Enjoy it
folks because if current long range model projections are correct...a
vastly different scenario will be in store for the region by New
Year/s Day.

Before then major weather feature of interest set to
arrive during the day on Friday as a synoptic-scale cold front
arrives from the west...and a weak disturbance begins lifting north
from the lower Miss Vly. Models suggest precip to begin extending
north into our region by Fri afternoon mainly due to weak isentropic
ascent in ongoing warm air advection ahead of the main front to the
west. Current thermal profiles suggest initial batch on Fri should be
all rain...with a gradual changeover to a RA/SN mix and eventually
all snow early Sat as cold air works in following FROPA. Beyond
this...fcst becomes a little clouded as the GFS takes the cold front
east quickly...while the ECMWF and GEM hang it up with continued snow
showers through the day Sat. Due to model uncertainty...have
maintained CHC pops through the day before things clear out for good
Sat night.

Heading into next week...all eyes will be on a major pattern shift as
a fairly significant ridge develops across the eastern Pacific.
Downstream...deep upper trough to rapidly dig south across the
central U.S. with a 1045+ mb high descending down the Plains by
midweek. Current models show 850-hPa temps as cold as -24C along the
MO/IA state border which could yield high temps in the middle to
upper teens by New Year/s Eve. Like I said folks...enjoy the Christmas
Day weather while you can!


.AVIATION...(For the 18Z TAFS through 18Z Thursday Afternoon)
Issued at 1147 AM CST WED DEC 24 2014

Stratus will stick around for several more hours, with gradual
improvement through the day and the evening. Expect the stratus to
break up overnight with VFR conditions prevailing for the remainder
of the forecast period. Strong southerly winds will pick up Thursday
morning and persist through the day. Expect these southerly winds to
sustain around 20 kts, with gusts to around 30 kts.



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