Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 290502

Area Forecast Discussion
National Weather Service Grand Junction CO
1102 PM MDT THU JUL 28 2016

.SHORT TERM...(Tonight through Friday night)
Issued at 325 PM MDT Thu Jul 28 2016

The broad Subtropical Ridge remains anchored near Las Vegas. Near
record heat has continued today. In NW flow aloft, moisture has
eroded for the north and central zones. Marginal moisture lingers
in the south with dewpoints in the 40s and precipitable water
values around 0.5 inch. Afternoon storms formed over the Abajo and
San Juan Mountains and then slowly moved over valleys to the
south. A few storms may continue until midnight across eastern
Utah and far SW Colorado producing gusty outflow winds but little
to no rain.

Friday increasing mid-level moisture continues to rotate around
the High mainly into eastern Utah. Late-day lightning and gusty
winds appear the main threat for eastern Utah. SW Colorado
marginal moisture erodes for only isolated storms there. Very warm
conditions continue.

.LONG TERM...(Friday night through Thursday)
Issued at 325 PM MDT Thu Jul 28 2016

Moisture continues to advect into south Friday night that may keep
a few overnight storms there.

The pattern change remains the same in the latest models adding
forecast confidence. Timing may be a bit faster than previous
runs. Over the weekend and into next week, upper Lows track
across the northern tier of states. This flattens the Subtropical
Ridge and nudges it east. This allows marginal monsoonal moisture
to push back north of the Four Corners beginning Saturday evening.
The GFS has precipitable water values approaching one inch in the
southern valleys through Monday, decreasing to around 0.75 inch in
the north.

Beginning Tuesday, strengthening SW flow will bring deeper
moisture into the region. The south could see precipitable water
climb to around 1.25 inches which would raise flash flood concern.

Temperatures drop through the new week returning to near normal by
Wednesday. Rising dewpoints will make for muggy conditions.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1102 PM MDT Thu Jul 28 2016

Airports will continue to experience VFR conditions through the
next 24 hours. However, isolated thunderstorms are possible over
the mountains from 17Z/Friday through 03Z/Saturday. This activity
may generate brief, but strong and unpredictable outflow winds at
airports in close proximity to mountains.


.GJT Watches/Warnings/Advisories...




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