The National Weather Service has announced that a winter weather advisory is in effect for Southwest Colorado from 9 p.m. Monday through 11 p.m. Tuesday.

Moderate to heavy snowfall is expected, producing wet and snowpacked roads in the San Juan Mountains in Montezuma, Dolores and La Plata counties.

By Wednesday morning, 5 to 10 inches of snow is expected at 9,500 feet, with up to a foot on some westerly slopes above 10,000.

Southwest winds will gust at 35 to 45 mph above 10,000 feet, creating areas of blowing and drifting snow, the weather service said. Visibility may be reduced to less than a half-mile on Tuesday night.

In Montezuma County, isolated showers are expected after 4 p.m. on Monday, with a high temperature of 51 degrees. Monday night, there’s a 70 percent chance of showers, with a low of 38 degrees and winds of 5-10 mph.

On Tuesday, rain and snow showers are likely beginning in the morning, with a high near 48 degrees. Tuesday night, there’s a 50 percent chance of rain showers starting at 10 p.m. The low temperature is expected to be 30 degrees.

Sunny skies are expected Wednesday through Sunday, with highs rising from about 49 degrees on Wednesday to 58 by Sunday. Overnight lows are expected to be about 32 degrees.

In La Plata County, isolated showers are expected after 11 p.m. Monday, with a high temperature of 52 degrees. Monday night, there’s a 70 percent chance of showers, with a low of 38 degrees and winds of 5-10 mph.

On Tuesday, rain and snow showers are likely to begin before 4 p.m., with a high near 49 degrees. Tuesday night, there’s a 50 percent chance of rain showers before 1 a.m., and a slight chance of snow showers after 3 a.m. The low temperature is expected to be 30 degrees.

Sunny skies are expected Wednesday through Sunday, with highs rising from about 51 degrees on Wednesday to 58 by Sunday. Overnight lows are expected to be about 28-30 degrees.