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Area forecast discussion 
National Weather Service Kansas City/Pleasant Hill MO
542 am CST Mon Dec 29 2014

issued at 348 am CST Monday Dec 29 2014

Early this morning water vapor imagery shows a large trough
dominating the continent, though the local flow across the Central
Plains is rather flat thanks to the troughs' current position. Also
of note is the 1058mb surface high working its way south through the
Canadian rockies and Canadian plains. It's this cold surface high
that will dominate the weather across our section of the country
over the next couple of days with the broader trough the major
player towards the end of the week.

The Canadian high will ooze farther south over the next couple of
days as the Continental trough keeps the prevailing westerlies
anchored across the central and Southern Plains states. However, as
the high slides under the jet aloft, there will likely be
sufficient lift and frontogenic forcing to squeeze some snow out of
the skies. Threat of light accumulations of snow continue to look
very limited for Monday night due to the dry sub-cloud layer and
general iffy moisture profile advertised by the models, but flurries
look like a good bet given the near surface temperatures in the
diacritic growth range will be brought by the surface high. Have
continued to keep a mention of them into Tuesday morning as the
surface high continues to work its way south.

Cold temperatures will then prevail both Tuesday and Wednesday, with
Tuesday night likely to see the coldest temperatures. Current
forecast is expecting sub-zero temperatures to make it as far south
as the northwest corner of Missouri and northeast Kansas. Add a
little light wind, as our area will be on the edge of the high and
not under the calm center, and wind chill readings in that corner of
the world may reach below -15f early Wednesday morning. Temperatures
will rebound a little Wednesday, but will still be well below normal;
thus a second night of near zero temperatures will be in store,
though with slightly warmer wind chill values.

System for the tail end of the work week and into the weekend
continues to give forecasters fits. Models continue to jump around
as they attempt to settle on a solution for what will happen with
the cutoff low expected to develop from the Continental trough over
the Great Basin later this week. Progressive models runs continue to
push the ejecting cutoff low farther south. This has had the affect
of pushing the onset of our next major precipitation event back some
12 hours, from Thursday night into Friday. Still, there is enough
consistency to continue advertising a significant event for the end
of the week, though precipitation type will likely dictate just how
"significant" the event is. Currently, confidence is not overly high
on precipitation type owing to the very real uncertainties in the
forecast solutions, but some accumulating snow will likely fall from
the sky early in the New Year.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 542 am CST Monday Dec 29 2014

VFR conditions currently are prevailign at the tmerinals, which will
persist through the morning hours but likely end this afternoon and
low level clouds shift south along the leading edge of a cold surface
high. Confidence in where these clouds will come in is a little low
owing to the uncertainty around the potential snow that will
accompany the surge of cold air. Winds should pick up a bit overnight
as the cold air oozes in along with some potential for snow. Though,
at this time the snow will likely be light enough to not accumulate.


Eax watches/warnings/advisories...



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