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National Weather Service Goodland Kansas
921 PM MST Wednesday Dec 17 2014

issued at 921 PM MST Wednesday Dec 17 2014

Update issued to continue Winter Weather Advisory through 12z
Thursday. Light snow has begun to fall in northern have
left snow amounts in for now. Rest of forecast on track.

Update issued at 828 PM MST Wednesday Dec 17 2014

Update issued to take into account latest observation trend over last few
hours. Area remains in the 20s under a thick low level cloud
cover. Fog continues to be major factor at this time along with
patchy freezing drizzle. Latest VAD wind profile from kgld does
show middle-level winds now northerly and with this colder air is
starting to wrap into system. Next couple of hours from north to
south will affect changeover to some light snow...ending drizzle.
It will be a slow transition though as low levels winds still
carrying east-southeast component due to slow movement eastward of the low
over south/south central Kansas. Advisory still ongoing and plan
on updating in next hour or so.


Short term...(this evening through thursday)
issued at 257 PM MST Wednesday Dec 17 2014

Not too much to add from earlier updates of the forecast. Areas
of freezing fog...still dense mainly from Thomas and Logan
counties westward into Kit Carson and Cheyenne counties...and
freezing drizzle continue across much of the area. Light snow is
expected to develop and move across mainly the southeast half of
the area.

So through much of the night...freezing and frozen precipitation
will continue along with some visibility restrictions. Roads and
sidewalks have become slick because of ice accumulation. Accidents
have occurred on Interstate 70 and at least one school was
dismissed early. Based on reasoning above...have decided to issue
a Winter Weather Advisory until 5 am Montana/6 am CT Thursday. Snow
accumulations look to remain below an inch in most locations with
amounts near 1 inch in the southeast portion.

Precipitation looks to be done by sunrise on Thursday.
However...boundary layer moisture remains rather high. It does
appear that the models may be drying out near surface conditions
too fast. That makes sense with the very moist air mass and lack
of strong subsidence and winds. So at this time am continue areas
of fog and patchy freezing drizzle in the morning. The night shift
will need to take a close look if additional highlights will be

Do not expect a lot of warming on Thursday. Expect cloud cover to
last most of the day. There does not appear to be a lot of mixing
or wind tomorrow as well. So tended to go more toward the cooler

Long term...(thursday night through wednesday)
issued at 1244 PM MST Wednesday Dec 17 2014

Long term forecast concerns are the possibility of light precipitation
Friday...Saturday evening...and again on Monday.

The upper level westerly flow pattern will have a couple
progressive troughs embedded in it that will pass over the
Central High plains region through the end of the week and into
the weekend. The first will move across the High Plains on Friday
and the second slightly weaker one will move across the High
Plains on Saturday night. The European model (ecmwf) and GFS are hinting at a very
slight chance of precipitation across the southwest portion of
the forecast area early Friday while the NAM remains dry. All
models remain dry through middle-day Sunday. The near surface flow
remains mainly westerly and have gone with dry conditions with
temperatures warming through the weekend and becoming warmer than
average Saturday and Sunday. Expect the snow cover over northeast
Colorado to still be an issue that will create temperatures cooler
than what models are currently indicating in the guidance values.

Between Sunday and Monday the large high pressure area over the
eastern Pacific moves over the West Coast of the United States
while the mean upper trough over the eastern 2/3 of the country.
The patterns seems to stall here and become more amplified with
strong northwest flow aloft over the central rockies that
continues through Wednesday as the pattern begins to become a
little less amplified. As a result...expect cooler temperatures to
extend further south through the northern and Central Plains
states with a prefrontal through deepening along the eastern
Colorado border on Sunday with a cold front expected to move
through the Central High plains region Sunday night and early
Monday morning. Expect an area of light precipitation to sweep
southward across the forecast area during the day on Monday behind
the front as a vorticity maximum embedded in the northwest flow aloft
punches into the region. With temperatures still above average for
this time of year on Monday...currently expect a mix of precipitation

With unidirectional flow through the column on Tuesday...expect
windy conditions on Tuesday behind the front. Extended guidance is
showing this increase in wind...but may still be underdone. Will
have to continue to evaluate as that time period approaches.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 438 PM MST Wednesday Dec 17 2014

Both taf sites will see persistent vlifr conditions through midday
Thursday. Expecting vv002-004 for ceilings through 16z...along with
freezing fog reducing visibility to 1/4sm to 1/2sm. Some light
snow will work into both areas by 05z as winds go from more
easterly to light/variable. After 16z Thursday...IFR/MVFR mix with
3-6sm in fog and ceilings ranging from ovc006 up to broken-
ovc020-025. Winds easterly 5-10kts becm variable by midnight
tonight...then becoming west-southwest 5-10kts after 15z-16z Thursday.


Gld watches/warnings/advisories...
Kansas...Winter Weather Advisory until 5 am MST /6 am CST/ Thursday for

Colorado...Winter Weather Advisory until 5 am MST Thursday for coz090>092.

NE...Winter Weather Advisory until 5 am MST /6 am CST/ Thursday for



short term...Buller
long term...Lockhart

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