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Area forecast discussion 
National Weather Service Grand Junction Colorado
402 am MDT Tuesday Apr 28 2015

Short term...(today through wednesday)
issued at 402 am MDT Tuesday Apr 28 2015

A ridge will stretch across the forecast area today...pushing
drier air into eastern Utah and northwest Colorado. Moisture from the
last disturbance rotating around the upper low centered over Texas
will focus over SW Colorado in the morning...then decrease throughout
the day. A band of lesser moisture will stretch NE across the
central Colorado mts. The nam12 shows isolated to scattered showers and
a few thunderstorms possible from the moisture left behind by
this system. These will concentrate over the San Juan Mountains...
with isolated convection expected over the Uncompahgre Plateau...
The Flattops and the central Colorado mts near the Continental Divide.
These should dissipate quickly after sunset.

The SW U.S. Ridge will continue building over the area Wednesday,
which should be warmer and drier. Only isolated afternoon showers
are expected over the San Juan Mountains and the Uinta mts of NE
Utah.

Long term...(wednesday night through monday)
issued at 402 am MDT Tuesday Apr 28 2015

Low amplitude flow through the long term period with the main
westerlies north of Colorado. This results in a warming trend into
Thursday and Friday...several degrees above climatology. However a
shallow cold front does drag across the north by Thursday
evening...not quite making it to the i70 corridor. Isolated
showers and thunderstorms may form along this front late Thursday
afternoon/evening...but much of region stays dry.

Friday through Sunday...shallow cold/stationary front stays in the
vicinity of the central rockies. Weak short wave energy from the
California coast will move across the intermountain region and
keep the air mass unsettled for diurnal driven showers/storms.
Much of the afternoon convection will be hugging the higher
terrain toward the Colorado spine.

Monday...the GFS and Euro models are in fair agreement that a closed
low circulation off the California coast will move inland. This
feature will reinforce the threat of afternoon convection over the
mountains.

&&

Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 937 PM MDT Monday Apr 27 2015

Scattered showers east of a line from kcag-kril-kcez will slowly
dissipate by about 08z. The precipitation will have more areal
coverage south of Interstate 70. Mountain tops will be locally
obscured by these showers...though only ktex will see brief MVFR
ceilings until about 08z. The other taf sites will remain VFR
overnight.

On Tuesday 18z-03z expect isolated -shra...with scattered -shra and
isolated thunderstorms over the San Juan Mountains mountain will be locally
obscured again. Flight conditions at all taf sites should remain
VFR.



&&

Gjt watches/warnings/advisories...
Colorado...none.
Utah...none.
&&

$$

Short term...cirrocumulus
long term...pf
aviation...cirrocumulus

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