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Area forecast discussion 
National Weather Service Grand Junction Colorado
344 PM MST Tuesday Dec 1 2015

Short term...(tonight through Wednesday night)
issued at 318 PM MST Tuesday Dec 1 2015

Some cirrus brushing the northestern part of the forecast area...remnants
from broad closed low circulation over the Midwest. Otherwise high
pressure dominates tonight with strong radiational cooling.
Stratocumulus field has formed in the Uinta Basin...some erosion
has occurred on the eastern side. With no mixing...expect the stratus
or fog layer will expand tonight.

Strong inversions will continue to trap moisture low to the
ground and produce fog and low stratus over the Colorado northwest plateau and
in the eastern Uinta Basin. These will slowly dissipate toward
noon...through come back soon after sunset Wednesday evening. A weak
shortwave trough will ride over the top of the Great Basin ridge
Wednesday and bring mainly middle and hi cloud to the northern half
of the area during the day. No precipitation is expected from it.

Middle and hi cloud will clear after midnight allowing the inversions
to redevelop with areas of fog and low cloud in the valley bottoms
in central Colorado and Utah as well as the Uinta Basin and northwest plateau.

Long term...(thursday through tuesday)
issued at 318 PM MST Tuesday Dec 1 2015

Thursday will see the Ridgeline pass overhead with gradually
strengthening SW flow spreading over the area through Friday.
Another weak trough will skim across NE Utah and northwest Colorado Friday afternoon
and evening with on hi Montana isolated showers expected.

As this trough move through then plunges down the Front Range
Friday night and Sat...the European model (ecmwf) is a bit deeper and further south
with it than is the GFS and shows a bit of split flow Sat. This
would result slightly more showers over the Colorado central mts...
mainly on northwest facing slopes.

Sunday and Monday will see dry ridging again followed by another
shortwave trough dealing a glancing blow to northwest Colorado Tuesday.


Aviation...(for the 00z tafs through 00z Wednesday evening)
issued at 343 PM MST Tuesday Dec 1 2015

MVFR ceilings and isolated dense fog will persist over the Uinta Basin
and stretch into northwest Colorado tonight and Tuesday morning...otherwise
widespread VFR is expected through the forecast period.


Gjt watches/warnings/advisories...


long term...cirrocumulus

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