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Area forecast discussion 
National Weather Service Grand Junction Colorado
404 PM MDT Tuesday Oct 13 2015

Short term...(tonight through Wednesday night)
issued at 402 PM MDT Tuesday Oct 13 2015

Temperatures rebounded nicely across the forecast area today
after a cold start with big diurnal swings occurring. This trend
continues tonight with clear conditions and light winds under a
ridge of high pressure. This will allow for excellent radiational
cooling once again. However...there was a fairly pronounced thermal
belt evident in surface observation this morning...generally between 7 and 8k.
Temperatures within this band were running 10 degrees warmer on average
and should be expected once again tonight. Overall...little change
anticipated for the next 12 to 18 hours.

Negatively tilted upper ridge expected to remain over our County Warning Area
beyond Wednesday night for continued dry and unseasonably warm
daytime temperatures. Wide variation between maximum and min
temperatures will persist as dew point temperatures will remain
very low.

Long term...(thursday through tuesday)
issued at 402 PM MDT Tuesday Oct 13 2015

Thursday should be a repeat performance of Wednesday/S weather
..continued dry with similar temperatures as Wednesday. Expect
some high clouds to begin drifting into our County Warning Area from the SW on
Thursday...but expect minimal influence on maximum temperatures.
Expect a mild night at most locations as high clouds increase
across our area. Raised min temperatures higher than previous
grids for Thursday night at many locations...and even then may not
be high enough in eastern Utah and SW Colorado.

As the upper low presently off the Southern California coast drifts
towards our County Warning Area on Friday...subtropical moisture is expected to
spread northward into our County Warning Area with showers and some thunderstorms
advecting or developing from the south during the day and reaching
all portions of our County Warning Area by early evening. Then as the upper low
opens up and moves slowly across the region Friday night and
Saturday expect precipitation to increase across our County Warning Area and
continue into Sunday...with snow levels lowering. Snow
accumulations should generally be above the 10 thousand foot level
through Sunday. Maximum temperatures should be running close to normal
..while min temperatures will likely be well above normal due to
cloud cover and higher dew point temperatures.

Models still showing a secondary trough moving across our area
Monday and Tuesday with 700 mb temperatures lowering 3-4 degrees c
during that period. Although this situation does not look quite
as moist as the previous still looks like widespread
precipitation. And if latest model guidance is correct...snow
levels should be lowering to near the 8000-9000 foot level in the
northern mountain zones...and 9000-10000 foot level in the
Southern Mountain zones.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 1142 am MDT Tuesday Oct 13 2015

Light winds and clear conditions will persist through midday
Wednesday. VFR pattern remains in place.


Gjt watches/warnings/advisories...


Short term...jdc/jrp
long term...jrp

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