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Area forecast discussion 
National Weather Service Grand Junction Colorado
206 PM MDT Tuesday Sep 2 2014

Short term...(this evening through Wednesday night)
issued at 205 PM MDT Tuesday Sep 2 2014

Continued dry across the area through Wednesday night...though
some high- based convection until early this evening over the
western San Juans and Abajo Mountains associated with low level
convergence and a weak short-wave as seen on water vapor satellite
imagery...being acted upon by daytime heating.

Warming trend should continue through Wednesday...with 700 mb
temperatures generally about 2 degrees c higher on Wednesday than
today. Surface temperatures across our area early this afternoon
running 2 to 4 degrees f higher than yesterday for the same
time...with some warmer exceptions that include Aspen 9f warmer
and Meeker 7f warmer. Should be a little milder tonight and
Wednesday night than last night due to warmer airmass. Last night
min temperatures dropped into the 30s at many higher valley
locations...including Silverton which reached the freezing mark.

Expect breezy surface winds on Wednesday for much of west central
and northwest Colorado...perhaps a tad stronger than today. These winds
and low relative humidity values will result in some fire weather concerns Wednesday

Long term...(thursday through tuesday)
issued at 159 PM MDT Tuesday Sep 2 2014

Models remain in good agreement. The trough becomes stretched
across the northern plains out to beyond the northern California
coast. In resulting SW flow aloft moisture works into the region
Thursday afternoon and evening. A weak disturbance is also pulled
across the forecast area overnight that may provide some support
for nocturnal storms.

Friday-Tuesday...the region remains in SW flow aloft between the
trough to our northwest and subtropical high center to our southeast. Marginal
moisture between 0.8 and 0.5 inches precipitable water values will produce
scattered late day showers and thunderstorms. The northern trough
digs down the West Coast on Monday then progresses through The
Rockies on Tuesday. This may bring an increase in storm coverage
but with a drier air mass introduced in its wake.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1037 am MDT Tuesday Sep 2 2014

Isolated high-based thunderstorms possible this afternoon and
early evening over the western San Juan Mountains. Breezy
westerly surface winds today mainly northwest Colorado. Otherwise... VFR
conditions should persist across the area through Wednesday.


Gjt watches/warnings/advisories...


Short term...jrp
long term...Joe

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