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Area forecast discussion 
National Weather Service Grand Junction Colorado
415 am MDT Monday Sep 1 2014

Short term...(today through tuesday)
issued at 412 am MDT Monday Sep 1 2014

Eastern Utah and western Colorado will enjoy just about the driest
conditions in a month as the precipitable water on the 00z kgjt
sounding was only 0.48 inches. Dew points have fallen into the 30s
and will continue falling today. Northwest flow aloft will continue
through the day with gradually decreasing speed. The subtropical
high will push west into New Mexico by the end of day...shutting
off monsoon moisture. Subsidence will prevail with this afternoons
cape being close to none. Today will initiate an nice warming
trend.

Tonight and Tuesday...zonal flow will set up across the Continental U.S. This
period as high pressure blankets the southern tier of states and the
jet strays over the northern border with Canada. This will leave
skies on the clear side and allow temperatures to push back to above
normal for early September. The NAM is beginning to hint at some
isolated convection over the southern mountains during the heat
of the day as a strong eml sets up. Moisture at the top of this
layer appears to be related to return upslope flow over the Front
Range. Profiles suggest little rainfall potential but there could
be some very gusty winds near virga. The steep middle level lapse
rates will also contribute to breezy afternoon conditions on
Tuesday.

Long term...(tuesday night through sunday)
issued at 412 am MDT Monday Sep 1 2014

Tuesday night and Wednesday...lowering heights in the west leads to
to backing winds over the central rockies and a warm advection
pattern for Wednesday. Still Little Hope for rainfall without a
moisture tap and temperatures will be warning another few degrees
for Wednesday. Highs will range from the upper 80s and 90s over
the western desert valleys to the 70s over the mountains. This
should end up being some 3 to 5 degrees above normal.

By Wednesday night the subtropical high will have receded back to
Texas and the western Gulf and southwest winds aloft will be
increasing over the forecast area. On Thursday the first hint of a
return of monsoon flow appears as the Pacific trough moves inland
and moisture and precipitation are projected moving north over
eastern Arizona. A passing weak cold front in the westerlies north of
the area will act to Bend the monsoonal plume to the NE through
the end of the week. This tendency is more pronounced in the European model (ecmwf)
and the Canadian...while the GFS keeps a significant monsoonal
plume over the center of the forecast area through the weekend.
Continued the high chance of rain across the area starting
Thursday...with a bit of focus east of the line from Rangely to
Grand Junction the Blanding.

&&

Aviation...(for the 12z tafs through 12z Tuesday morning)
issued at 412 am MDT Monday Sep 1 2014

VFR conditions with nearly clear skies will prevail for the next
24 hours.

&&

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

$$

Short term...cc/15
long term...15/cc
aviation...cirrocumulus

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