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National Weather Service Grand Junction Colorado
1056 am MST sun Nov 29 2015

issued at 1056 am MST sun Nov 29 2015

Infrared satellite indicates enhancing cloud tops across the San Juans
and central mountains. Expecting snow to increase in coverage
throughout the afternoon today with a southwest to northeast
movement. Rap and hrrr suggest scattered showers passing along the
I-70 corridor again this evening...a little further east than
yesterday's snow. Will keep an eye on consecutive model runs and
observations to pinpoint the area of heavier snow for this

Update issued at 542 am MST sun Nov 29 2015

The quasi-stationary and broad band of snow which extended from
the vicinity of Nucla to Craig began to shrink early this morning
as models had predicted. Snowfall had largely ended over the
Grand Valley...Roan Plateau and central Yampa River basin. While
snow lingered over the Uncompahgre Plateau...the Grand Mesa...and
adjacent valleys its intensity has diminished significantly. As
the morning progresses...expect lingering snowfall to become more
localized and any additional accumulations will be light. Therefore
..remaining winter weather advisories across the area have been


Short term...(today through monday)
issued at 335 am MST sun Nov 29 2015

The closed upper level low center that provided snowfall overnight
will lift into Wyoming today. Meanwhile...the low center that
brought the round of snow to western Colorado and northeast Utah Friday
night has made its way back to the Utah/Nevada border early this morning
and will make one final run through eastern Utah/western Colorado tonight while
the aforementioned low/vorticity lobe hangs out in Wyoming and
waits for a final pass over Colorado Monday night. Upper level qg
forcing increases again by midday over eastern Utah and then over western Colorado
through midnight tonight. Unlike what happened this past night...middle
level frontogenetical forcing is not as well aligned with the qg
forcing so do not expect as robust coverage of snow...except over
the higher terrain of the central and southern parts of eastern Utah/western Colorado.
There may be a few passing snow showers for adjacent valleys...
but not expecting any significant accumulations there. Several
inches likely over the high country though through tonight. As we
have seen the past 2 days...details of each surge of forcing will
have to be fine tuned closer to the approach of each wave.

Upper level flow finally turns out of the west to northwest by
Monday morning. The flow will be moist and moderately
accumulating snowfall can be expected in the favored west to
northwest facing high country regions on Monday. Right now it
looks like about 3 to 8 additional inches of snow for these areas.
Will need to monitor possible advisories.

Temperatures will remain below normal through Monday under the
influence of the cold upper level low passing over the region.

Long term...(monday night through saturday)
issued at 335 am MST sun Nov 29 2015

Moisture in northwest flow finally dwindles Monday night as the
storm system responsible for periods of snow from Thanksgiving
into the early part of week shifts farther eastward over the
northern plains. Consequently...look for any lingering snow to
diminish by sunrise Tuesday.

Dry and milder conditions still on track Tuesday through Thursday
as a deepening trough over the eastern Pacific builds a ridge over
the area at midweek. Models have diverged on propagation of the
trough eastward across the Great Basin with the GFS the more
progressive. However...both solutions have abandoned cutting off a
closed low circulation over the southwest at the end of the week.
According to the GFS solution...the next chance for snowfall
arrives Friday while the European model (ecmwf) holds off on the onset of
precipitation until Saturday. Given both a lack of temporal
consistency and model agreement confidence in either solution is
poor. Therefore...held off making any substantive changes to the
going forecast and limited probability of precipitation to the lower end of the chance

Unseasonably cold temperatures will moderate during the week with
ridging...described above...and subsequent southwest flow later in
the week.


Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1056 am MST sun Nov 29 2015

The closed low which has been plaguing the region the last few
days will send another piece of energy into the region today. Snow
showers are already beginning to enhance over the San Juans and
will impact ktex...kase and kege this afternoon. Snow will become widespread
over the central and southern mountains through this evening and
bring conditions down to IFR for hours at a time. Impacts will
continue through today with eastern Utah and southwest Colorado
sites clearing by morning. Fog development is definitely possible
at many sites tonight and Monday morning.


Gjt watches/warnings/advisories...


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