Kevin Myatt is The Roanoke Times' weather columnist.

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A missing player returns to the weather stage next week, and it could make things messy.

I mainly mean "messy" in terms of messy forecasts ... but the weather itself could get messy, too.

The southern branch of the jet stream, largely inactive this winter, will begin to intensify over the weekend into next week. A strong low pressure system moving along that river of wind high in the atmosphere will likely spit out a series of disturbances across the southern tier of the United States.

These hard-to-time disturbances, unlike their Canadian cousins that zipped through the area on frigid northwest winds last week, will be able to tap Pacific and Gulf of Mexico moisture, throwing some of that moisture northward over colder air at the surface. This is called an "overrunning" effect.

The messy part is figuring out the timing of each disturbance and the depth of cold air that will be encountered by each one.

The whole gamut of precipitation types is possible: rain, freezing rain, sleet and snow. Precipitation types could vary with each new piece of energy traversing the rapid flow of air across the southern U.S.

Strong high pressure near the West Coast is in the process of breaking down, but it will be able to deliver one final shot of Arctic air to the eastern United States over the weekend. That will snap us out of our brief warmup that could take the mercury to 60 today, just a week after it dropped into the single digits across Southwest Virginia.

High pressure in central and eastern Canada will hold cold air across the eastern U.S. early next week. There is some chance the high could press cold air down the eastern slopes of the Appalachians, trapping it in a familiar "cold-air damming" setup that often leads to winter weather mayhem in our region.

Monday and Tuesday will bring the best chances for any wintry precipitation. The early indication is that freezing rain and sleet are more likely than snow ... not a pleasing thought for snow lovers or sun seekers.

Overrunning situations are always dicey, as even subtle changes in the mix of moisture and cold air can change the whole formula.

As the week goes along, temperatures will become milder as cold high pressure releases its grip. Also, the large low itself may make a move inland, sweeping in more warm, moist air ahead of it. So, from Wednesday on, the chances of just plain old rain increase.

Overrunning may make our cup run over with something next week.