textproduct: Missoula

DISCUSSION

KEY MESSAGES:

- Unsettled, cool, and showery conditions persist through the weekend.

- Mountain snow Sunday morning will create uncomfortable conditions for backcountry recreation, especially along the Continental Divide.

- Widespread frost and freezing temperatures Sunday through Tuesday mornings.

While showers continue to rotate cyclonically through the region they are winding down. Both satellite and radar clearly shows northerly flow is developing as a cold front drops out of Canada. Low level moisture interacting with this Canadian Cold Front will produce the last of robust showers along the boundary that could produce graupel. While most of the snow will fall above 4000 feet, a mix of rain and snow is possible north and east of Missoula at lower elevations.

The next phase of this cool spring system is the cooler than normal temperatures. Breaks in the clouds this evening have allowed temperatures north of I-90 to lower into the 30s. Overnight lows in the 20s are more likely along the Continental Divide. Monday morning however, 20s will be widespread in western Montana and limited to higher valleys of north-central ID, IE Elk City, Dixie, and potentially as low as Pierce. Temperatures moderate Tuesday morning but will still lower close to 30F for many and upper 20s along the Continental Divide.

The rest of the week will see a warming trend. The drying trend is no longer definitive as multiple weak waves will dive south out of Canada, producing chances for showers throughout the week.

AVIATION

Precipitation has turned to snow above 4500 ft MSL. Snow will be possible at KBTM this morning. North winds will gust 15 to 20 kts at most terminals today.

MSO WATCHES/WARNINGS/ADVISORIES

MT...Winter Weather Advisory until midnight MDT Sunday night for Bitterroot/Sapphire Mountains...Butte/Blackfoot Region... Potomac/Seeley Lake Region...West Glacier Region.

Frost Advisory until 9 AM MDT Sunday for Flathead/Mission Valleys...Missoula/Bitterroot Valleys.

Frost Advisory from 8 PM Sunday to 9 AM MDT Monday for Flathead/Mission Valleys...Missoula/Bitterroot Valleys.

ID...None.