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National Weather Service Grand Junction Colorado
754 PM MST Wednesday Nov 25 2015

issued at 754 PM MST Wednesday Nov 25 2015

The Wind Advisory will expire at 8pm. The cold front is crossing
into eastern winds will remain elevated but are
expected to remain below advisory criteria for the remainder of
the evening.

A few returns on radar have begun to develop across northwest Colorado
but are very light and are not likely reaching the ground yet. No
changes to current forecast at this time.


Short term...(this evening through Thursday night)
issued at 245 PM MST Wednesday Nov 25 2015

Stronger winds aloft have finally started to mix to the surface
with gusts 40 to 50 miles per hour being realized in the valleys of eastern Utah
and west-central Colorado. Will hoist a Wind Advisory for these areas
through the evening hours.

A closed upper level low pressure center over northwest Nevada will
become detached from the northern stream in which it originated and
become cut-off by early Friday...only moving as far east as
western Utah during this period. Besides an overall weakening of
the upper low...dry air in the middle to upper levels continues to be
forecast to reside over The Heart of eastern Utah and western Colorado.
Deeper moisture will skirt the uintas and far northwest well as
the eastern San Juans tonight and Thursday. These areas will have
greatest chances of precipitation through Thanksgiving day and
night...aided by qg forcing (nw) and jet dynamics (se). At the
surface...a polar cold front along the Wyoming/Colorado border will sink
south while low pressure over eastern Utah will move into western Colorado
Thanksgiving day...pulling the colder air southward. Temperatures
aloft also cool several the mild weather of today
will be history come Thanksgiving day as temperatures run 10-15
degrees cooler. In the areas with expected higher precipitation
chances...uintas...NW Colorado...and northern...central and San Juan
Mountains...snowfall of 2-4 inches for the 36 hours period ending 5 am
Friday is likely.

Long term...(friday through wednesday)
issued at 245 PM MST Wednesday Nov 25 2015

The forecast through this period is still fairly low confidence
due to the nature of a cut-off upper level low wobbling over the
Great Basin vicinity...though there is agreement among the models
that it will generally lift north into Idaho/Wyoming by Sunday and meander
over the plains early next week. Models vary on ingredients to
produce precipitation Friday through Sunday. There appears to be
some convergence around lower level low pressure over SW Colorado and
an inverted trough extending north through western Colorado...with upper
level jet dynamics and qg forcing increasing from time to time.
There just is not a strong consensus on all coming together for
any significant precipitation...and again...moisture depth is a
limiting factor. That being said...there seems to be a relative
maximum for precipitation chances over southern Colorado Friday afternoon and
night...and again Sunday.

If the upper level low gets out to the plains by early next
week...our flow will turn out of the west to northwest and dry out
even more. However...cut-off lows always have a mind of their we will see how this plays out. Temperatures through the period
should remain near to below normal.


Aviation...(for the 00z tafs through 00z Thursday evening)
issued at 444 PM MST Wednesday Nov 25 2015

An extended windy period will exist through this evening as a cold
front approaches Colorado. Surface low pressure feature will pass
through west to east during the overnight hours...but the low
pressure impacting the region remains over the Great Basin
throughout the next 24 hours. As cooler air advects into the
region tonight...winds will remain elevated but also generally
remain southwesterly. Low level wind shear expected as kase and kege through about
02z this evening. Precipitation will begin to move in
overnight...but will be spotty so no major impacts expected at taf
sites at this time.


Gjt watches/warnings/advisories...
Colorado...Wind Advisory until 8 PM MST this evening for coz020.

Utah...Wind Advisory until 8 PM MST this evening for utz022-027-029.



short term...Ben
long term...Ben

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