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Area forecast discussion 
National Weather Service Denver/Boulder Colorado
902 PM MST Friday Dec 26 2014

issued at 903 PM MST Friday Dec 26 2014

No changes to the forecast at this time as the storm continues to
gradually wind down. Radar show the weak echoes across the
northeast plains slowly decreasing as the flow aloft becomes more
northwesterly and drier air moves into the state. Scattered
showers will continue in the mountains as low level moisture
remains trapped over western exposures. Temperatures will be
getting colder overnight as the cloud cover diminishes and fresh
snow on the ground maximizes radiational cooling.


Short term...(this afternoon through saturday)
issued at 300 PM MST Friday Dec 26 2014

The upper low is currently passing over Colorado with the drier
westerly flow expected soon. This will help dry the plains out
from west to east. Until then...expect areas of light snow to
continue late this afternoon and early be over by or
just after midnight. Accumulation will be less than an inch...with
perhaps up to 2 inches over the High Mountain peaks and over the
far eastern plains near the NE and Kansas borders. As the drying
clears skies out tonight...light winds will allow temperatures to
cool down below zero in the mountains and in the single digits
over the plains. There may be some patchy fog over the newly
fallen snow...but at this time there is no strong signature of
where or how thick. For now will leave it out of the forecast.

Strong north-northwesterly flow aloft will push over the state
Saturday with weak warm advection. Besides a few clouds over the
mountains...the airmass will be pretty dry and stable so no precipitation
and very little cloud cover is expected. With sun shining but snow
cover on the ground...temperatures will be limited with how much
warming occurs. Expect about 3-9 degrees warmer tomorrow for the
plains...however the mountains may not warm much at all with high
cloud cover coming in during the afternoon.

Long term...(saturday night through thursday)
issued at 300 PM MST Friday Dec 26 2014

For Sunday strong northwest flow dominates as the trough continues to move
southeast. Surface high pressure moves into western Colorado with Lee
troughing over the plains. Temperatures will rebound slightly into
the lower to middle 30s for the plains. The reprieve from snow will be
short lived as increased moisture will move into NE Colorado ahead of the
next incoming trough Sunday afternoon. This moisture over the
mountains combined with increased lapse rates between 7-8 c/km will
aid in bringing light snow showers to the northern mountains by
Sunday afternoon and evening. Upper level winds will change to a
more westerly direction by Sunday evening as the next trough drops
into Utah. The best chance for snow will be Sunday night into Monday
morning with the jet moving southeast into central Colorado bringing the
cooler and more unstable portion over the southern half of our
County Warning Area. Some light accumulation will be possible with more along the
Palmer Divide. With the back door Arctic cold front moving into
eastern Colorado by 12z Monday snow will make its way on the plains with
temperatures only getting into the lower teens.

On Tuesday the cold temperatures will continue with highs not making
out of single digits and lows overnight Monday getting a few degrees
below zero. With the cooler air combined with moisture and the jet
overnight snow showers will continue through Tuesday into Tuesday
evening...especially over the eastern Colorado border where qg dynamics
are decent.

For Tuesday night into Wednesday a surface high pressure will move
south into eastern Colorado helping to dry out the plains while
keeping some light snow over the mountains from lingering moisture.
The low pressure system will be centered just south of the Great
Basin by 12z Wednesday keeping moisture over the southern mountains and
strong SW flow at upper levels. There is little jet support but some
snow will be possible over the SW portions of the state Thursday
into Friday. For our region however the moisture will not make it
far enough north to bring snow but we will have cloud cover on
Friday. Temperatures will begin to rebound on Wednesday with highs
in the middle teens and onto Thursday and Friday where we will finally
get above freezing.


Aviation...(for the tafs through 06z Saturday evening)
issued at 903 PM MST Friday Dec 26 2014

Ceilings and visibilities will improve after 06z as drier air
moves in from the northwest. Minimal aviation impacts are expected
on Saturday as winds will be light and skies somewhere between
partly cloudy and mostly sunny.


Bou watches/warnings/advisories...


short term...kriederman
long term...Bowen

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