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Area forecast discussion 
National Weather Service Grand Junction Colorado
553 PM MDT sun may 24 2015

Short term...(tonight through Monday night)
issued at 350 PM MDT sun may 24 2015

Upper low centered over south central Wyoming continues to wrap
moisture around the back side and into our northern zones this
afternoon. Areas of rain and High Mountain snow will continue
through this evening...with diminishing returns expected as the
night wears on. After midnight...weak subsident flow settles over
the region further decreasing showers. Still...conditions remain
very moist and isolated showers likely to linger as favorable northwest
orographic flow remains in place. Localized snow accumulations up
to 4 inches will be possible over the park and Gore ranges and
possibly The Flat Tops. Coverage and impacts on travel are not
expected to be widespread...so will not be issuing any highlights
for the overnight period. Little change in temperatures tonight with
readings running 4 to 8 degrees below normal once again.

We will be under the influence of wrap around moisture and weak
channelized vorticity lagging the rear of the departing system on
Monday. This system is finally being kicked out by a low pressure
system arriving to the Pacific northwest. Lift and instability are
not as organized as the past few days as but will still be able to
pop afternoon showers over the County Warning Area tomorrow. Would expect the best
focus to be on the terrain as the shear is weakening through the
afternoon. Expect a noticeable downturn to the convection once the
sun set tomorrow as drier and more stable air moves in with a
transitory ridge arriving in the eastern Great Basin. Temperatures
look to make a rebound on Monday of about 3 to 6 degrees.

Long term...(tuesday through sunday)
issued at 350 PM MDT sun may 24 2015

The ridge axis moves over western Colorado to The
Spine of The Rockies by late Tuesday afternoon. This should
suppress the formation of early day convection and cut back on
probability of precipitation until noon. Models suggest the shower activity should be more
tied to the terrain. Tuesday evening confluent flow looks to be
setting up across the northern Great Basin with the interaction
between the split flow pattern focusing moisture and lift across
our northern County Warning Area. This may keep a bit of late night convection
going through the early morning hours and some small probability of precipitation were
retained. The models seem to be struggling finding some agreement
beyond this however. Another Pacific wave arriving to the Southern
California coast will phase with the low over the north to carve
out a more defined western trough. The models go with this but as
the southern piece of energy swings across the Desert
Southwest...they disagree on how northern energy drops in behind
it. The GFS keep a more aggressive solution from the past few
runs and brings a closed low over our County Warning Area by Friday...while the
Euro swings a sharper trough east of The Rockies. Either way
showers are enhanced and probability of precipitation rise through the late week period.
By next weekend however the GFS continues the pattern of wet
weekends while the Euro tries to dry things out building in a
warmer ridge. I know what solution I/M hoping for but confidence
not really high on verifying that at this time. Temperatures though the
week should rebound but look to stay short of normal.

&&

Aviation...(for the 00z tafs through 00z Monday evening)
issued at 536 PM MDT sun may 24 2015

Showers in the afternoon and evening thunderstorms will remain in
place through Monday. This evening...scattered to numerous
showers and embedded thunderstorms will cause ceilings to be
frequently below 5000 feet above ground level at kase...ktex...kege and kril through
about 04z this evening. Precipitation will decrease in intensity and
areal coverage overnight...then redevelop Monday afternoon.

&&

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

$$

Short term...jdc/15
long term...15
aviation...cirrocumulus

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