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Area forecast discussion
National Weather Service Grand Junction Colorado
941 am MST Wed Mar 1 2017

Short term...(today through thursday)
issued at 259 am MST Wed Mar 1 2017

Northwesterly flow has set up on the back side of the trough that
brought all the snow to the area yesterday. This flow will allow
some snow showers to form over favored northwest facing slopes but
minimal accumulation is expected. Under this flow, plenty of
drying has kicked in which will keep mostly sunny skies in the
forecast along and south of I-70 though partly to mostly cloudy
skies are expected for the northern mountains and most of the
northern valleys. Cold air will remain across the area with high
temperatures still running about 10 degrees cooler than normal for
this, the first day of meteorological Spring. All in all, a rather
uneventful day.

A few pesky showers may hang on over the northern mountains
Thursday as west to northwest flow continues but coverage will be
minimal at best. Sunny skies will prevail for most of eastern Utah
and western Colorado though, again, the northern mountains will
see a few more clouds than the rest of the County Warning Area. After a brisk
start to the day, temperatures will begin to warm up and though
still not quite reaching 'normal' values, it should be noticeably
warmer than Wednesday.

Long term...(thursday night through tuesday)
issued at 314 PM MST Tue Feb 28 2017

West to northwest flow will dominate the pattern Thursday night
and Friday with a broad ridge of high pressure overhead providing
dry conditions and warming temperatures. The upper level flow
should allow for enough mixing to prevent lower valleys from
developing strong inversions due to recent snowfall. Confidence is
high through Saturday as models remain in fairly good agreement
between models and run to run. Beyond Saturday, the models are not
in great agreement so low confidence exists Sunday through
Tuesday. The latest 12z GFS guidance is showing clouds increasing
Sunday ahead of a quick moving trough that brings rain and snow to
the region Sunday evening through Monday, mainly for the northern
and central areas of the County Warning Area. This trough appears cold enough for
snow levels lowering to the valley floors by Monday morning.
However, previous model runs did not show any weather system
impacting the region through the weekend into early next week,
with temperatures staying fairly mild. Since this is the first
instance of this colder and wetter solution occurring, decided to
keep slight chance pops in the forecast for Sunday and Monday and
trended towards the warmer guidance. Will Need More consistency in
the models before latching onto this solution.

&&

Aviation...(for the 18z tafs through 18z Thursday afternoon)
issued at 934 am MST Wed Mar 1 2017

VFR conditions will continue through the forecast period. A few
mid-level clouds will linger to the north of Interstate 70 in
northwest flow, but will not impact any terminal locations. Mainly
clear conditions expected overnight. A few areas of patchy fog in
valleys on Thursday morning, otherwise clear skies expected
through the day.

&&

Gjt watches/warnings/advisories...
Colorado...none.
Utah...none.
&&

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