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Area forecast discussion
National Weather Service Grand Junction Colorado
1029 PM MST sun Nov 17 2019

Short term...(tonight through Monday night)
issued at 113 PM MST sun Nov 17 2019

A weak jet speed maxima will pass over Wyoming and north-central Colorado
late tonight and early tomorrow morning producing some mid and
high level cloudiness over northern Colorado. A few flurries are
possible over the park, Elkhead and Gore ranges, which may persist
through Monday morning, then dissipate.

Monday afternoon and night will see moderate north-northwest flow aloft
gradually weaken and become more westerly as the ridge begins to
collapse. A developing storm will move into the Pacific northwest
and begin to dig south, while the persistent closed low off of
Baja California begins to fill and show signs of lifting to the NE.

Long term...(tuesday through sunday)
issued at 113 PM MST sun Nov 17 2019

A significant change in the northern hemispheric pattern will play
out Tuesday through Friday. Model agree that a strong shortwave
will round the bottom of the trough over the Pacific northwest
Tuesday afternoon and night. It strengthens and forms a closed 500
mb low over northern California Tuesday evening while the baja low lifts
over Arizona as an open wave and begins to be incorporated into the
extensive longitudinal troughing over the western U.S.

The northern California closed low dives due south Wednesday as remnants
of the baja low lift over Colorado and Utah producing widespread
precipitation. This initial wave of valley rain and mountain snow
should reach The Four Corners just before sunrise Wednesday then
spread north throughout the day.

Thursday and Thursday night another shortwave develop over the
western Great Basin and dives SW and help kick the SW US low to
the northeast over Utah and Colorado. Expect widespread low elevation
rain and high elevation snow. Finally the main trough moves
through Thursday night and Friday morning with cold advection
driving snowfall down to the valley bottoms.

The front pushes out of the area Friday afternoon with high
pressure reestablishing over the Great Basin. This ridge is more
transitory and will slide east and over Utah and cirrus Saturday as
another pair of Pacific trough, one in the north and one in the
south, move into the western US by Sunday afternoon.


Aviation...(for the 06z tafs through 06z Monday night)
issued at 1028 PM MST sun Nov 17 2019

Some high clouds will move over the area through the next 24
hours. No aviation concerns noted as VFR continues. Light winds


Gjt watches/warnings/advisories...


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