First, the forecast is for the ~9-15 day range (216-360 hour) range ... deterministic forecasts at this range will tend to have high uncertainty, so the best approach is a probabilistic forecast based on the ensembles. But, it would also be useful to take a look at the preceding weather to get a feel for the snow.
First, let's take a look at the GFS and ECMWF operational runs for this period:
Both the GFS (7-day shown above) and ECMWF insist a pretty solid ridge will dominate the west coast after our quick brush with the 'wind-storm' on Monday.... looks really bad for snow as we dry out and upper-level temps approach summer-like levels.... snow levels look to reach 10k+ ft. and stay that way the entire week before we reach the timeframe of the ski trip.... sorry!
Both models continue to keep the ridge frozen along the west coast through the 9-12 day range. GFS MOS keeps temps and snow-levels high the entire time also
Now, let's look at the GFS ensemble (below): at ~216 hours almost all the models support the strong west-coast ridge (and model spread was fairly low up to this point). Only 1 member shows a flatter ridge, but still with pretty warm upper-level temps. A few embedded short-waves occur sporadically in the 190-220 hr range, but too warm and too far north to really help with the snow situation.
http://mp1.met.psu.edu/~fxg1/ENSPRS_12z/ensloop.html#picture
From 216-240 hrs, the solutions begin to diverge from each other radically. The strength and position of strong surface and upper-level Lows in both the Gulf of Alaska (GOA) and along the East coast varies... these beasts ultimately have a lot of influence on the change in upper-level patterns at this point, so predictability remains low after 220 hrs.
A number of the runs in the 220-300 hr range bring the GOA Low further west, helping to flatten out the ridge and lower thicknesses. A few of these really take off and build a positively-tilted trough which would possibly be great for snow levels and Mt. Hood snow... but these are the outliers. About half the runs are favorable for Mt. Hood snow in the ~300-360hr range. The other half provide a random assortment of various amplitudes of ridging. Uncertainty is really too high to get a good picture of the wx over this period, though the odds say that conditions will be improving over those of the 150-200 hr range.
The CPC supports the above-normal temps also:
In conclusion, the snow looks pretty crappy at the beginning of the 'ski vacation' period. There are fairly good odds that things may improve near the weekend of Feb. 21-22nd, but it is just as likely that they will not.
Sorry! This has been a pretty poor winter for west coast mountain snow so far.
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