Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 211609

Area Forecast Discussion
National Weather Service GRAND JUNCTION CO
1009 AM MDT Fri Apr 21 2017

Issued at 1004 AM MDT Fri Apr 21 2017

Snow was decreasing this morning behind the strong system which
passed over the area last night. Though snow continued to fall
over some central and northern mountain areas, rising temperatures
and reduced snowfall rates have prevented accumulations on
roadways. Instability and orographics will continue to bring
scattered snow showers to Colorado`s northern and central
mountains during the day, but additional accumulations will be
light and localized. Therefore, cancelled the winter weather


.SHORT TERM...(Today through Saturday)
Issued at 430 AM MDT Fri Apr 21 2017

Cool air is filtering in behind a departing cold front that passed
over Eastern Utah and Western Colorado overnight. The current
infrared satellite image is showing cold cloud tops associated
with this front passing east into the Front Range of the Rockies.
However, some lower convective type clouds are lingering over the
Western Slope this morning.

These lingering clouds are convective in nature and will support
continued snowfall of an additional 2 to 4 inches over the
Northern and Central Colorado Mountains through this evening.
Since these clouds are convective in nature locally higher
accumulations will be possible through this afternoon. A Winter
Weather Advisory remains in effect through 6PM MDT this evening
for portions of the Northern and Central Mountains. For additional
info please see our web page or the Winter Weather Advisory
message DENWSWGJT.

Cool dry northwesterly flow will persist over the forecast area on
Saturday as a ridge of high pressure slides east over the
intermountain west. As the ridge builds over the CWA a brief
warming trend will develop.

.LONG TERM...(Saturday night through Thursday)
Issued at 430 AM MDT Fri Apr 21 2017

The current satellite water vapor image is showing a ridge of high
pressure building over the west coast with a trough of low
pressure positioned over the northern Rockies. The 0000Z ECMWF and
0600Z GFS20 have initialized well with these synoptic scale
weather features and remain in good agreement through at least the
middle of next week.

Both of these forecast models show a ridge of high pressure
building over the area Sunday with 500mb heights reaching 574dm
over Grand Junction and 700mb temperatures at 7.6 C. This spells
seasonally warm temperatures for the area on Sunday and Monday.
In fact it looks like the Grand Valley could reach into the upper
70s to lower 80s. This warm up will be short lived as the
jetstream slides south over Colorado and Utah on Tuesday.

This jetstream will support precipitation over the mountains
possibly through the end of next week with the potential for
afternoon thunderstorms. With mild midweek temperatures and
persistent precipitation we could see some rises in the rivers
and minor rock and mud slides along the passes. This is not
guaranteed but will be a possibility to keep an eye on as we
approach next week.


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 430 AM MDT Fri Apr 21 2017

Cool northwesterly flow will fill in behind a departing cold
front today. Lingering instability will support convective clouds
across the forecast area with lingering showers in the lower
elevations and snow showers over the mountains. For the most part
expect VFR conditions at or above 6,000 feet at most terminals.
However, MVFR is anticipated at the higher elevation terminals and
locally lower cigs will remain a possibility through mid morning.






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