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Area forecast discussion 
National Weather Service Pueblo Colorado
251 PM MST Thursday Nov 26 2015

Short term...(this evening through friday)
issued at 248 PM MST Thursday Nov 26 2015

..periods of snow tonight...
..More light snow on Friday...

Busy day of weather for this Holiday. Looks like most areas have finally
changed over to all snow...except over the extreme southeast corner of the
state...which could hold on to some freezing rain through this evening.
Highlight in general have so far worked out pretty well. Main
concern in the short term will be the snow potential especially this
evening. It looks like the best window for accumulating snow will be
from now through 06z tonight. The latest model runs...including the
hi res WRF...hrrr...and 18z NAM...all show bands of heavy snow
developing this evening and moving from SW to NE during this time.
The quantitative precipitation forecast forecast is difficult since it is next to impossible to say
at this point exactly where these heavy mesoscale bands develop...if
they develop as prognosticated. It is not out of the question that some
local spot could see significant snowfall tonight if one of these
bands is persistent over the same area. The hrrr has the snow
bullseye over the southern sangres and Spanish Peaks...while the NAM sets
up the heaviest snow over the northern sangres and Fremont County.
Based on the latest observation and model consensus...appears the best bet
for seeing higher snow totals will be over the sangres...wets...and
southern I-25 these mesoscale bands translate in from the
SW. Have upgraded this area to a Winter Storm Warning for tonight.
Expected snowfall is in the 6-10 inch range...possibly higher in the
heaviest band. Rates of 1-2 inches an hour will be possible with
these bands. Elsewhere...the ongoing forecast of 2-4 inches for the
plains and 4-8 for the mountains and higher terrain looks on track.

Friday...should see a lull in the action Friday morning through
early afternoon...especially north of Highway 50. Some isolated to
scattered shsn will continue over the area. By late afternoon another
wave of snow showers should develop from the SW...and this will
bring back the threat of some light snow accums to the area.
Depending on what happens overnight...may have to extend some of
the ongoing warnings and/or advisories on Friday. Temperatures will be
well below average as 700 mb temperatures of minus 15 or lower continue to slide
southward down the southern Front Range. GFS-based guidance seems a tad too have leaned towards the warmer NAM which still brings
highs only in the lower 20s across the plains. Looks like a very
raw day across the County Warning Area. Rose

Long term...(friday night through thursday)
issued at 248 PM MST Thursday Nov 26 2015

Friday night the upper low will be centered over the Great Basin with SW
flow aloft continuing over the forecast area. At the surface over the eastern
plains...low level upslope easterly winds will continue along with
the potential for light snowfall. An upper level disturbance coming
around the front side of the upper low into western Colorado...should help
enhance snow chances across the Continental Divide...especially the eastern San
Juan Mountains...and could increase snowfall over the northern sangres and
Pikes Peak area.

On Sat...there is not much change in the position of the upper
low...and by afternoon the upper disturbance should be out of the
area. This is expected to lead to a decrease in precipitation chances...with
generally just some isolated to scattered chances in most areas. However
there may continue to be persistent light snowfall across the eastern
San Juan Mountains through much of the day. Temperatures across the southeastern plains will
still be cold...with highs ranging from the middle 20 to lower
30s...maybe a little warmer near the mountains the San Luis valley
should see highs in the upper 30s to around 40...with mostly 30s in
the upper Arkansas River valley.

Sat night the upper low is expected to begin lifting northeastward
into southwestern Wyoming. This will bring another upper disturbance through western Colorado and
another round of increased chances for snow. Another disturbance is
then expected come around the upper low during the day Sunday...once
again enhancing precipitation chances over the mountains...and then over eastern areas
Sun night. Temperatures on sun should be a little warmer over the southeastern
plains...but still below average with readings in the 30s to lower
40s. The upper Arkansas River valley and San Luis valley should still
see highs mostly in the 30s.

The latest model runs show the upper low center then moving into
extreme northestern Colorado by midday Monday...bringing westerly winds to the
forecast area and drier conditions by afternoon. Although the
central mountains should still be seeing some light snow. The upper low is
the expected to quickly move east into Iowa by Tuesday morning...leaving
the forecast area with dry conditions. A weak upper disturbance is
forecast to move across the area on Tuesday night and Wednesday...but at this
time the models do not show any precipitation associated with this system.
High temperatures by Wednesday should be around average. Thursday it looks like a
shortwave ridge will be over the area for another dry day.


Aviation...(for the 00z tafs through 00z Friday evening)
issued at 248 PM MST Thursday Nov 26 2015

At kals...VFR conditions likely to go downhill after 00z as ceilings
start to drop and scattered shsn move into the valley. Could see some
light snow accums by morning.

At kpub and kcos...IFR to occasionally LIFR at kcos will persist
through this evening and possibly into Friday morning. Will see some
improvement Friday afternoon... but another round of shsn is
expected late afternoon or early Friday evening. Kpub also will see MVFR
to IFR ceilings overnight with a period of light to modt snow possible
especially this evening. Taf sites should be MVFR to VFR by
tomorrow afternoon but could see occasional restrictions by late
in the day as more shsn move in from the SW. Rose


Pub watches/warnings/advisories...
Winter Weather Advisory until 8 am MST Friday for coz076-077-

Winter Storm Warning until 8 am MST Friday for coz072>075-

Winter Weather Advisory until 5 PM MST Saturday for coz067-068.



Short term...rose
long term...28

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