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Snow predicted for early this week will increase avalanche danger in the backcountry, but it will also help clear out inversion-related pollution in the valleys of northern Utah, authorities say.

The Utah Avalanche Center released a special avalanche bulletin Sunday, warning people without expert skills to stick to ski resorts through Tuesday because snow is expected to make human-triggered slides of up to two feet "likely" in the mountains of northern Utah, according to forecaster Drew Hardesty.

A cold front moving through overnight Sunday will be "very weak," bringing mostly rain mixed with some snow in the valleys and an uneven distribution of up to 8 inches of snow in the mountains, said National Weather Service meteorologist Monica Traphagan. Another, stronger storm system is predicted for Tuesday and Wednesday.

That system is expected to help clear the air. The Utah Department of Environmental Quality will continue a red air alert on Monday for Salt Lake, Davis, Weber, Utah, Box Elder and Cache counties, meaning the conditions will be unhealthy for sensitive people, but the conditions will improve to yellow, or moderate, by Tuesday. Tooele County has a yellow air alert for Monday and will improve Tuesday to green status.

High pressure is expected to return later in the week, though, possibly producing more dirty air in the valleys, Traphagan said.