Area Forecast Discussion
Issued by NWS Grand Junction, CO

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FXUS65 KGJT 160949

Area Forecast Discussion
National Weather Service Grand Junction CO
349 AM MDT Sun Oct 16 2016

.SHORT TERM...(Today through Monday)
Issued at 333 AM MDT Sun Oct 16 2016

High clouds associated with a vigorous jet stream are filling into
the forecast area this morning. At the surface southerly winds are
blowing warm air into Eastern Utah and Western Colorado. This warm
air is helping to keep temperatures in the valleys in the mid 50s
to mid 60s.

The 0000Z ECMWF, 0600Z GFS20 and NAM12 have all initialized well
with the current synoptic weather pattern and remain in good
agreement through at least Monday. The models are forecasting that
a vigorous jet stream will begin to pass over the area today. Wind
speeds at the core of this jet stream will reach 155 kt. This will
result in strong winds over the ridge lines and mountain tops
today reaching 20 to 30 mph sustained with gusts to 65 mph. With
heating of the day some of these strong winds will mix into the
valleys where gusts to 50 mph will be possible. These strong gusty
winds have prompted a Wind Advisory for many locations across the
CWA. For more information please see the Wind Advisory NPWGJT.

In addition to the strong winds, today will be another warm one
with afternoon high temperatures exceeding seasonal normals by
several degrees. Several record high temperatures may even be
broken today. The combination of these high temperatures and
strong winds may raise some concerns for the fire community this

.LONG TERM...(Monday through Saturday)
Issued at 301 PM MDT Sat Oct 15 2016

Little change is seen in the pattern and sensible weather for our
CWA until late Tuesday and Wednesday when a more significant
shortwave trough is likely to roll across our CWA. Continues to be
some significant differences between GFS and EC models on
intensity and speed of movement of trough over our area. EC has
been consistently showing a very progressive system with moisture
mainly remaining north of I-70, then moving well east of our area
by late Wednesday afternoon. The GFS is now leaning more towards
the EC solution, having shown in yesterday`s runs a deepening
trough over our CWA which kept the troughiness and moisture over
our CWA into Thursday morning. Due to consistency considerations,
have more confidence in the EC solution than the GFS.

Both models then develop upper high/ridge into the western states
for the remainder of the week, with the EC building a higher
amplitude ridge than the GFS, with the EC supporting higher
temperatures across our CWA than the GFS.


.AVIATION...(For the 06Z TAFS through 06Z Sunday night)
Issued at 1048 PM MDT Sat Oct 15 2016

Light...decoupled valley wind overlaid by a strong southwest wind
will lead to areas of llws through mid to late morning sunday. As
temperatures warm and begin to mix the atmosphere these winds
should re-emerge at the surface and bring another concern with
gusts over 30 mph and possibly as high as 50 mph through sunset on
Sunday. VFR conditions will prevail with cigs above 120kft agl.
The probability of blowing dust limiting vsby to near mvfr is very
small but can not be ruled out...confidence is low so no mention
in this round of tafs.


CO...Wind Advisory from noon today to 9 AM MDT Monday for COZ001-003-

     Wind Advisory from noon today to 8 PM MDT this evening for

UT...Wind Advisory from noon today to 9 AM MDT Monday for UTZ023-025-

     Wind Advisory from noon today to 8 PM MDT this evening for



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