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Area forecast discussion 
National Weather Service Grand Junction Colorado
1141 PM MDT sun Oct 23 2016

Short term...(tonight through Monday night)
issued at 138 PM MDT sun Oct 23 2016

A broad ridge just east of the forecast area will continue sliding
east as a large trough spins off the Pacific northwest coast.
High and mid level cloud will spread over the area tonight and
Monday. The flow aloft will gradually become more south-southwest Monday
through Monday night, this being helped by a shortwave trough
rotating around the underside of the Pacific low. This flow and
the trough will draw subtropical moisture north through Arizona
and into Utah and by late Monday afternoon this moisture will
spread into eastern Utah. Overnight Monday this activity will
spread east and across western Colorado. Have increased clouds and
precipitation across the forecast area Monday and Monday night.

Long term...(tuesday through sunday)
issued at 138 PM MDT sun Oct 23 2016

As the shortwave trough moves east of the area Tuesday, the flow
aloft becomes more westerly and begins to dry out. Westerlyorographics
should become a stronger player in the location of precipitation
Tuesday afternoon and evening.

Overnight the next big ridge begins to build west of the forecast
area. The flow over the Colorado and Utah mountains will become more
northwesterly and moisture will continue to decrease. The system
will be rather warm with snow levels hovering around 9000 feet
Tuesday, so snow accumulations will be very localized and at high

Wednesday and Thursday will be dry with another strong ridge
dominating the western U.S with a deep trough off the West Coast.
On Friday a strong closed low over the California coast fills and
slides northeast. The tail of this trough is projected to cross
the area late Friday night and Saturday, with the bulk of its
energy traveling around the northern periphery of the ridge.
Sunday should be dry with the ridge dominating.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1138 PM MDT sun Oct 23 2016

VFR conditions are expected to prevail overnight ahead of an
approaching weak weather system. This weather system will bring
increasing clouds to the area tomorrow with rain showers possible
by late morning in Utah and late afternoon in Colorado. The
atmosphere will take a while to moisten tomorrow so be on alert
for virga and gusty winds near showers.


Gjt watches/warnings/advisories...


Short term...cirrocumulus
long term...cirrocumulus

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