textproduct: Missoula

DISCUSSION

KEY MESSAGES:

- Anticipate cooler temperatures and periods of valley rain and mountain snow this week.

A low pressure system is moving onshore over Washington today. This system will move east, bringing widespread rain and snow to the Northern Rockies later today and tonight. Snow levels tonight are expected to lower to around 4,000 to 5,000 feet, bringing accumulating snow to the mountains. The heaviest snow is expected to fall across the Mission Mountains up into Glacier National Park, where snowfall amounts have increased compared to recent days. Several inches of snow can be expected in these areas above 5000ft by Tuesday afternoon. Those with backcountry plans through the overnight, need to be prepared for wintry conditions. The valleys across northwest Montana, including Kalispell, may see periods of snow mixing with the rain, though the accumulating snow will remain in the mountains.

Another weather system will bring more rain and mountain snow to the area Wednesday through Thursday. A cooler Canadian air mass will move south and west over the Continental Divide by Thursday morning, which could lower snow levels down to 3,000 feet for locations along Highway 2. If we see any impacts in the valleys due to snow, Thursday morning would be the day, where around one-half to 1 inch of snow could accumulate before sunrise.

By Friday, warmer air will move into the region ahead of another storm system, causing snow levels to rise. This storm system will move through over the weekend, lowering snow levels once again and bringing another round of widespread rain and snow.

AVIATION

Increasing clouds and precipitation are expected to prevent widespread dense fog across western Montana and north-central Idaho on Tuesday morning. However, slight visibility reductions will still be present with light valley rainfall and mountain snow, along with mountain obscurations as snow levels lower to around 4,000 to 5,000 feet. Scattered showers on Tuesday will briefly reduce visibility and lower ceilings. Expect mountain obscurations to continue through Tuesday as well.

MSO WATCHES/WARNINGS/ADVISORIES

MT...None. ID...None.