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Area forecast discussion
National Weather Service Grand Junction Colorado
437 am MDT Mon Apr 24 2017

Short term...(today through tuesday)
issued at 435 am MDT Mon Apr 24 2017

Mid and high clouds are lingering around the area this morning as
the first in a series of weather disturbances exits the region.
The next disturbance is on schedule to arrive this afternoon
bringing breezy conditions, showers and a potential of
thunderstorms to the forecast area, mainly north of I-70.

Showers will spread south this evening becoming snow above 8,000
feet. The northern and central mountains of Colorado will see
between 4 to 6 inches of snow fall this evening with the greatest
accumulations occurring overnight. Similar snow accumulations
will also impact the San Juan Mountains tonight into Tuesday as
well. Since this is a late season snow event we went ahead and
issued winter weather advisories for these mountain locations.
For more details see the Winter Weather Advisory on our web Page
or see denwswgjt.

Much cooler temperatures and a continued threat of showers and
thunderstorms are expected once again on Tuesday as a cold trough
of low pressure passes over the forecast area.

Long term...(tuesday night through sunday)
issued at 435 am MDT Mon Apr 24 2017

The current satellite water vapor image is showing a low pressure
system centered over the southeastern portion of the Continental U.S. While
another low pressure system is pushing into the Pacific northwest.
The satellite water vapor image is also showing plenty of moisture
heading our way. Both the 0000z European model (ecmwf) and 0600z gfs20 have
initialized well with these synoptic scale weather features and
remain in good agreement through the forecast period.

Both of these forecast models suggest a much cooler and active
weather pattern is in store for eastern Utah and western Colorado
as a vigorous upper level jetstream directs several disturbances
over the area. Snow levels are anticipated to drop to between
5,000 and 6,000 feet Tuesday night as a trough of low pressure
slides across the area bringing with it another round of breezy
conditions and the potential for precipitation. Overnight lows are
anticipated to fall into the mid to upper 30s in the valleys
Tuesday night and upper teens to mid 20s across the higher

The action will slow down a bit on Wednesday as cool moist
northwest flow continues to filter into the area. By Wednesday
evening yet another weather disturbance is forecast to impact the
area with a reinforcing blow of cool moist air. Afternoon temperatures
at lower elevations will struggle to get out of the mid 50s for
the second half of the week as a much deeper low pressure system
slides out of the Great Basin into the forecast area. This low
pressure system will drive snow levels closer to the valley floor
on Friday night. Please keep an eye on the forecast this week,
especially is you have sensitive outdoor plants, as details
unfold and prepare to take action to prevent cold weather damage
to your sensitive outdoor vegetation.


Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 435 am MDT Mon Apr 24 2017

Mainly VFR conditions are expected today with periods of showers
at many of the local terminals, especially north of I-70. Breezy
conditions are expected later today ahead of an approaching
weather disturbance which will bring widespread shower activity to
the area with mountain snows expected this evening and overnight
into Tuesday.


Gjt watches/warnings/advisories...
Colorado...Winter Weather Advisory from 9 PM this evening to 9 PM MDT
Tuesday for coz004-010-012-013.

Winter Weather Advisory from midnight tonight to 9 PM MDT
Tuesday for coz018-019.



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