Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 302357

Area Forecast Discussion
National Weather Service Grand Junction CO
557 PM MDT SAT JUL 30 2016

.SHORT TERM...(This evening through Sunday night)
Issued at 320 PM MDT Sat Jul 30 2016

As high pressure slowly flattens out due to a passing trough this
evening, moisture will transport into the Four Corners from the
west and southwest. The 12z GFS initialized on the wet side from
the actual 12z GJT sounding with the NAM much more
representative. That being said, the NAM increases precipitable
water well in excess of an inch by Sunday while the GFS hangs
back about one third of an inch less. That`s a huge discrepancy
and seems to be an issue with handling the passing trough. The
SREF takes more of a middle ground, so thinking the NAM may be a
bit rambunctious with its solution. In any case, expecting showers
and thunderstorms to continue through the night tonight and focus
to be more in western Colorado and to the Continental Divide on

.LONG TERM...(Monday through Saturday)
Issued at 320 PM MDT Sat Jul 30 2016

Low amplitude high pressure will remain over the southcentral US
through the week. Conditions will remain pretty similar Monday and
Tuesday with afternoon convection with wetting rains across the
Four Corners region and high-based convection across northeastern
Utah and northwestern Colorado. Temperatures will remain around or
just above normal for this time of year.

Moisture starts to increase again late Wednesday into Thursday as
an incoming trough from the west pushes the high pressure in place
to the east. A more classic monsoonal tap will increase available moisture
by the end of the work week. Moderate confidence on this solution,
since day to day model runs have been struggling with the onset of
this monsoonal tap.


.AVIATION...(For the 00Z TAFS through 00Z Sunday evening)
Issued at 557 PM MDT Sat Jul 30 2016

Increased moisture over the Four Corners region has resulted in
scattered showers and thunderstorms over the San Juan Mountains
and adjacent valleys. This activity is likely to impact both KTEX
and KDRO through 03Z, generating outflow winds to 30 MPH and brief
moderate to heavy rain. VFR conditions should persist and CIGS
are expected to remain above ILS breakpoints. Activity was more
isolated elsewhere so outflow winds are possible but rainfall is
unlikely. VFR conditions are expected from 03Z through around 18Z
Sunday. However, light showers may persist here and there during
the night and after sunrise Sunday Morning. Expect increased
showers and thunderstorms Sunday as moisture levels continue to
creep upward.


.GJT Watches/Warnings/Advisories...




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