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Area forecast discussion 
National Weather Service Grand Junction Colorado
529 PM MST Sat Jan 31 2015

issued at 525 PM MST Sat Jan 31 2015

The last strong push of precipitation has moved southward into New
Mexico this evening. While some snowshowers are possible through
this evening...significant accumulation has ended. With that in
mind...cancelled all the highlights. Will also drop probability of precipitation
reflecting trend of less precipitation for the mountains

Next concern will be fog for many of the valleys especially down
south where plenty of moisture remains in the atmosphere. Am
anticipating some dense fog advisories later tonight.


Short term...(tonight through Sunday night)
issued at 232 PM MST Sat Jan 31 2015

An upper trough and vorticity maximum will move across eastern Colorado this
evening and a deeper closed low will become established over
southern Arizona and northwest Mexico. As predicted a deformation zone
developed between these two systems...with the flow stretched
between the northwest to west winds over Wyoming and the upper plains
and the return flow around the closed low to the southwest. This
zone will keep precipitation going over the Colorado SW mountains this evening and
have left the Snow Advisory going through 03z.

Sunday and Sunday night the southwest low will continue moving
due south over the Baja California peninsula and the eastern trough will
strengthen over the Central Plains. This will bring drier northwest flow
aloft over the area. Embedded weak troughs in these
northwesterlies will increase clouds and showers over the northern
mountains later Sunday night.

Long term...(monday through saturday)
issued at 232 PM MST Sat Jan 31 2015

For the first week of February the familiar January pattern
continues...with a ridge along the West Coast. This will
generally bring mild and dry conditions to the forecast area. The
exception is for the northern Colorado mountains through Wednesday. An
energized Aleutian low will throw disturbances over the top of
the West Coast ridge that will then brush the NE forecast area
with snow and blowing snow. These passing systems will be quite
mild with snow level somewhere around 7000ft. For the park/Gore/
Flattops... Monday through Wednesday snow totals may be up to 4
inches below 9000ft...up to 12 inches above that. These amounts
could be somewhat higher if the stronger GFS verifies.

The western ridge progresses inland Thursday through Sunday for
even milder and drier conditions into next weekend. There are
hints that the ridge will break early in the second week of


Aviation...(for the 00z tafs through 00z Sunday afternoon)
issued at 232 PM MST Sat Jan 31 2015

A broad line of dissipating showers will stretch across the area
from SW to NE and move steadily across the area toward the
southeast. Mountains in Colorado and southeast Utah will remain obscured
until about 03z then gradually clear. Valleys fog will form again
overnight...especially near rivers...and persist until about 18z
Sunday. MVFR conditions will be widespread south of a line from
kccu to kmtj to kbdg through about 03z...affecting kase...kmtj...
ktex and kdro. Toward midnight and overnight clouds will
clear...but valley fog will bring areas of MVFR ceilings and visibilities
affecting all the taf site through 18z Sunday.


Gjt watches/warnings/advisories...



short term...cirrocumulus
long term...Joe

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