COEUR d'ALENE - Holiday travelers will likely enjoy bare roads in the Pacific Northwest this week, but rain turning to snow may start as early as Saturday, according to climatologist Cliff Harris.

The dry weather isn't all good news, however, because it's causing poor air quality conditions and burning bans in the five northernmost counties of Idaho.

According to a forecast released Monday, Harris said Interstate 90 should be clear all the way to Seattle, and east into Montana. All paths to Boise should be good to go, as well.

"Things look good traveling to Grandma's house," he said. "But the high pressure front begins to break up on Saturday, and with that will likely come rain or snow."

That rain may turn to snow as early as Sunday evening, and snow should be a sure thing by Monday or Tuesday of next week.

"If I am right there will be snow - and several inches of it - by Monday or Tuesday," he said, adding the snow level will drop to 2,000 feet. "Our highs should be just above freezing and our lows will be in the 20s."

For now, Harris said, the days should remain chilly until Thanksgiving Day when temperatures should warm to the mid-40s.

"So there will be no ice to worry about, and there should be no problems on any of the passes," he said. "You should be good whether you're traveling north, south, east or west, at least for the trip there."

Those who wait to return late on Sunday might encounter some bad weather, he added.

Currently, a high pressure system is bringing the region dry weather and blue skies, but it is also trapping smoke particulates at the earth's surface level.

That has prompted a stage-one burn ban in North Idaho, said Ralph Paul, airshed coordinator for Idaho Department of Environmental Quality.

All outdoor burning is banned until the weather improves, he said.

"Idaho doesn't regulate wood stoves or home heating devices," Paul said, adding they can only ask people to voluntarily halt their use of wood burning stoves.

A high pressure ridge is blocking smoke from rising up higher in the atmosphere and there is no fresh air blowing in, either. The weather has created an air stagnation problem that is expected to be in place until Friday.

The air quality index is at a "moderate" to "unhealthy for sensitive" level. According to DEQ, at a moderate level air quality is acceptable, but a small number of people may face health problems. At the unhealthy for sensitive level, people with respiratory problems are likely to have some health effects from the smoke.

The unhealthy for sensitive levels are likely to occur overnight as woodstove burning increases and air mixture is poor.