Kevin Myatt is The Roanoke Times' weather columnist.

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This is going to be one messy weather forecasting week.

Yes, messy in the sense of the potential of multiple precipitation types, including the entire array of frozen precipitation.

But even more messy in the sense of being extremely complicated with way too many factors in play and so many scenarios to consider that computer forecast models will be busting computer chips and human meteorologists will be losing brain cells.

Let's start with the simple part: today.

An Alberta clipper storm system will dive southeastward, likely passing just north of our region.

Alberta clippers are low-pressure systems, usually weak, originating in or near the Canadian province of Alberta. They typically bring a reinforcing shot of Arctic air and light precipitation.

That's exactly what this one will do. With the low passing north of us, it will likely draw in enough warmer air that we could see a mix of rain or snow. Either way, any precipitation that falls should be light. Cold, windy weather with snow showers will follow the storm tonight.

But then comes the mess.

Multiple atmospheric disturbances will be riding toward the Eastern United States on both branches of the jet stream -- the cold northern branch and the milder but generally wetter southern branch.

High pressure will be well placed in Canada, at least on the front end, to push cold air southward into the East, banking it on the east side of the Appalachian Mountains.

As these disturbances come into play and moisture is pulled northward from the Gulf of Mexico over the cold air at the surface, there is a potential for significant snow and ice from Thursday night through Saturday in our region.

There are far more questions than answers at this point.

Will the disturbances stay separate, bringing several rounds of light to moderate precipitation, or will they be able to join forces into a stronger storm system?

Will the high-pressure system be strong enough to keep everything farther south, which might actually favor more snow in our area? Or will the warm, moist air be strong enough to overcome and turn everything to rain by Saturday?

The one thing that does appear likely at this point is that Southwest Virginia will get at least some wintry precipitation -- freezing rain, sleet or snow -- Thursday night and/or Friday.

Beyond that, so many things will have to be monitored the next 24 to 36 hours just to get a handle on what may happen.

My early inclination is the sort of light wintry precipitation event with temperatures near the 32-degree borderline like we've had repeatedly during this muted winter. I wrote last week that we would probably have at least one more ground-whitening event -- this might be it, though it might be whitened by sleet more than snow.

But there is still at least some potential that this could become the major winter storm I wrote that I did not expect to see in the ongoing weather pattern. If there is a major storm in this, I fear that it would be ice rather than snow.

I'll be keeping up with the developments on my weather blog through the week. Tune in to blogs.roanoke.com/weatherjournal/ for the latest.