If the plants are sitting there waiting they need to get back in the ground. If you are planning to choose cold climate types (most conifers on the market are) they can be bought and planted this month without basis for concern. Fall is the ideal time to plant hardy stock.

Where the predicted "vicious" winter could be expected to be a problem is with marginal kinds, mostly those from the southern hemisphere, that make up a minor percentage of the selection, and are present at garden centers here primarily because a few conifer specialists that grow rarer kinds in Oregon are in the wholesale business.

Even with potential for earlier frost? I was thinking they might not be able to establish good roots?? Haven't bought anything yet but am ready to roll. Nothing marginally hardy; I've been burned too many times out here; got used to Seattle climates and when we moved out here learned the hard way that it's all about the microclimate not the "zone". Do you think a particular mulch would be a good idea or just the soil itself would be protection enough?
Thanks, bboy, always enjoy reading your opinions.

If you do plant, definitely mulch. I prefer arborist's chips. Call any nearby arborist, and they will likely give you them for free. Wood chips also increase the mycorrhizal activity in the soil. Conifers like that.

Roots will grow whenever the ground is not frozen. A frost doesn't mean the ground is frozen.

If you plant intact roots before the fall root rush of that particular kind of plant then you get good immediate rooting out into the new site. This annual burst of root elongation occurs when the top has matured and stopped growing in the fall. However, since potting soil and field soil are so often different from the soil of the final planting site, and because deformed roots are so prevalent among nursery plants in this age of container production it's pretty much a basic procedure to bare root at planting time. But if a plant can be so processed without cutting or otherwise damaging most of the existing root tips these can be placed in the hole in position to continue growing. It seems if these have been kept moist and intact during the bare-rooting things could continue as before.

Roots don't grow much during winter.

New roots appear in spring, after the top starts growing.

You want the same soil texture throughout the entire rooting area, so movement of water into and out of the root zone is not adversely affected. Intact rootballs (and small amended planting holes) surrounded by soil of a different texture often become too wet during moist conditions or too dry at times when water is less abundant. This can interfere with or prevent plant establishment.

My rule of thumb is, you can plant hardy stock any time the soil is neither frozen nor waterlogged. Even with an early frost, it will be some time before your soil is frozen to any depth. Soil freezes slowly so it will take a prolonged period of subfreezing temps before the root zone of the soil is frozen. Light overnight frosts don't count.

Container plants are winterized by sinking the containers into the ground, or a mulch or compost pile. How much better to go ahead and plant them!

I plant all winter, even in the snow. Late spring and summer are the most difficult times because of the need for additional watering.