Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 261640

Area Forecast Discussion
National Weather Service Grand Junction CO
1040 AM MDT SUN JUN 26 2016

.SHORT TERM...(Today through Monday)
Issued at 128 AM MDT Sun Jun 26 2016

Water vapor imagery showed drier air working across all but the
eastern San Juan mountains early this morning. As a result, clouds
were nearly nonexistent over eastern Utah and western Colorado
except for south-central Colorado.

Moisture over the San Juans will persist throughout the day which,
when combined with early sunshine will fuel scattered showers
and thunderstorms from midday into the evening. These storms will
be capable of producing wind gusts to 35 MPH along with small hail
and light to moderate rainfall. Meanwhile, sunny and hot
conditions are expected elsewhere across the region as dry
westerly flow continues. Debris clouds from moist convection
should largely diminish across the south during the night while
skies will remain clear to the north.

Conditions will be similar Monday as the high becomes centered
over central Utah. Drier air will slowly filter across the San
Juan mountains which will reduce afternoon thunderstorm activity.
Elsewhere, the week begins with another round of above normal
temperatures and sunny skies. Afternoon highs are expected to rise
by a degree or two above those forecast for today.

.LONG TERM...(Monday night through Saturday)
Issued at 128 AM MDT Sun Jun 26 2016

High pressure will remain in control for the first half of the
coming week with dry and hot conditions persisting into Tuesday.
The lower valleys of southeast Utah and west-central Colorado
could be flirting with triple digit heat once again. Afternoon
storms will be possible each day mainly over the southern and
central higher terrain. PW values will be fairly low across much
of the area while deeper moisture remains pooled across New Mexico
and Arizona.

By late Wednesday afternoon into the evening, better moisture will
begin to seep in underneath the high as the mid-level flow
shifts to the southwest with PW values heading above 0.75 inches
across SE Utah and SW Colorado with near an inch over the Four
Corners. This will lead to an increase in storm activity across
the area and prime the atmosphere for the latter half of the week
as PW values climb above an inch over much of eastern Utah and
portions of southwest Colorado on Thursday. An easterly wave
moving through New Mexico and Arizona will head into southern
California before lifting northward and shearing apart as it moves
into the Four Corners region Thursday and Friday. This allows
deeper moisture to be pulled up into the region as well. This will
result in a substantial increase in shower and thunderstorm
activity on Thursday and Friday as these embedded shortwave
disturbances also act on the deeper moisture in place. Much better
chance of heavy rainers and frequent lightning with this activity.
Coordinated with neighboring offices to raise POPs during this
period of enhanced activity. Could this be the signal of the start
of the monsoon? Regardless, the change to a wetter and stormier
pattern towards the latter half of the week will be noticeable.
Temperatures will also cool down towards near normal values under
increased clouds and showers.


.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1040 AM MDT Sun Jun 26 2016

VFR conditions will prevail across eastern Utah and western
Colorado over the next 24 hours. Some showers and thunderstorms
will develop over the San Juans after 17Z and continue through
03Z/Monday, with activity diminishing shortly after sunset. Expect
gusty outflow winds to be the primary concern potentially
affecting KTEX, KDRO and KMTJ.


Issued at 128 AM MDT Sun Jun 26 2016

Releases from area dams and management of water diversions will
likely add to flow in some rivers and streams. As a result,
waterways across the area will continue to run high, fast, and
cold through the coming weekend. Stay advised of the latest river
forecasts by visiting our website at


.GJT Watches/Warnings/Advisories...


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