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Area forecast discussion 
National Weather Service Grand Junction Colorado
303 PM MST Monday Jan 26 2015

Short term...(tonight through Tuesday night)
issued at 303 PM MST Monday Jan 26 2015

Temperatures have jumped well into the 50s across the lower
valleys this afternoon...with Grand Junction hitting 57 earlier
today. One degree off the record and tied for our warmest day
since the last day of November as strong ridging remains parked
over The Rockies. Satellite imagery confirms what the models have
been advertising over the past few days...lifting an upper low off
the Baja California California coast north northeast across Nevada and
western Utah. The best dynamics with this system will be passing
well to our west and with some stretching of vorticity fields and
sinking motions under the ridge...hope for significant
precipitation has diminished markedly. Still should see some high
based showers as models drag a wave of deeper moisture and
instability across the area Tuesday and Tuesday night. Specific
humidities although still expect a band of showers to lift north-northeast
across the forecast area Tuesday and Tuesday night. As the system
gets caught up into the ridge...expect some acceleration in
forward motion with the southern zones clearing out late Tuesday
night. With cloud cover increasing and weak cold air advection...temperatures will be
backing down off todays near record warmth.

Long term...(wednesday through monday)
issued at 303 PM MST Monday Jan 26 2015

The dampened trough moves east across NE Utah/northwest Colorado on Wednesday. Dynamic
forcing does not look impressive but westerly orographic flow and
a modicum of instability should help produce a couple inches of
snow over the northern Colorado mountains the chance should decrease rather
quickly moving southward where lesser moisture exists.

A large-scale mean upper ridge will persist across the western
states the last half of the week resulting in continued splitting flow
in off the Pacific Ocean. Models in agreement that another Pacific
trough moves across California into the western Great Basin Thursday-Thursday night
before closing off and then dropping southward into northern Mexico by
Sunday. This storm should focus moist southerly flow and
precipitation on southeast Utah/SW Colorado Thursday night through Sat...though the
central and north will have also have a chance. Key will be
temperature and how much warm air is advected northward ahead of
the trough. Current forecasted 700 mb temperatures around -3c or -4c
would support rain/snow mix at Durango and pagosa spgs Friday and
snow Friday night. Will have to keep an eye on the development of
this potential late-week storm for the south.

Models show a return to dry weather Sunday and Monday as the
aforementioned upper low/trough continues to drop farther away to
the south.

&&

Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1008 am MST Monday Jan 26 2015

VFR conditions will continue through this period. There will be an
increase in middle and high level cloud cover across the region
tonight and Tuesday ahead of a weak wave lifting northeast across
Nevada and western Utah with isolated showers developing over the
mountains of southeast Utah after 15z Tuesday morning.



&&

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

$$

Short term...jdc
long term...jad
aviation...jdc

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