The National Weather Service has issued a forecast calling for heavy rain in the western Montana valleys and snow above 6,000 feet starting Sunday and continuing through Monday, Labor Day.

Meteorologist Luke Robinson said hunters and those recreating in areas above 6,000 feet should be prepared for snow, ice and winter conditions.

"We have an early season storm system that will begin to develop sometime Sunday morning into the early afternoon across southwestern Montana," Robinson said. "During the day on Sunday it will track north along the continental divide up towards Canada. We are expecting it to be cool enough to help develop snow at elevations of 6,000 feet and above."

Robinson said the valleys in western Montana will experience periods of sometimes heavy rains through the period.

"Temperatures will struggle to get out of the 50's which they probably won't," he said. "We're expecting between half an inch and three quarters of an inch of rain here in the Missoula area. It's going to be a cool and wet Labor Day weekend."

Robinson said overnight lows in the higher elevations on Monday morning will drop below freezing, thus creating the possibility of snow.

"Our main concerns are really for those people who are camping or hunting in the backcountry," he said. "It's going to be very raw, and people who are planning to go out there should plan accordingly."