textproduct: Missoula

DISCUSSION

KEY MESSAGES:

- Cold front moves through the region today, leading to cooling trend, gusty winds, and scattered showers.

- Mild temperatures much of this upcoming week, with next system bringing precipitation Tuesday into Wednesday.

A Pacific cold front remains on track to move southeastward across the Northern Rockies today, with gusty west-northwest winds developing area wide by late morning to early afternoon. Peak gusts this afternoon will reach 25-40 mph across valley areas with gusts of 40-55 mph over mountain and backcountry areas.

Southwesterly flow ahead of this front continues to transport subtropical moisture into northwest Montana and north-central Idaho this morning. The heaviest precipitation is forecast along and Idaho and Montana border, with valley areas seeing up to half an inch of rainfall and mountain areas seeing storm total amounts of 0.50-1.25 inches of precipitation. A flood watch remains in effect across Lincoln County through Sunday morning, where there is the potential for flooding of small streams and creeks from the combination of rain and snowmelt. Rain shower activity will focus along the frontal boundary, moving south of I-90 by this afternoon, with activity generally ending across northwest Montana.

The Northern Rockies will be under a dry and mild zonal (westerly) flow pattern Sunday into Monday. Above average temperatures will return with valley highs reaching into the 50s and 60s. Westerly breezes will develop each afternoon with valley gusts reaching 15-25 mph.

The next Pacific system arrives Tuesday into Wednesday, with a plume of moisture bringing widespread precipitation across north- central Idaho and northwest Montana. Snow levels will start above 6,000 feet Tuesday afternoon as precipitation arrives, before dropping near 4,500 feet by Wednesday morning as a cold front pushes through. Snow accumulations will generally focus above pass level, with a slushy inch or two of snow at Lookout and Marias Pass.

AVIATION

Pacific moisture continues to stream into northwest Montana and north-central Idaho this morning ahead of a Pacific cold front. This cold front will track through northwest Montana from 21/1200-1800Z, moving south of I-90 thereafter and reaching the divide by 21/2100Z. Mountain obscurations will be common through this morning, with periods of lower ceilings near 2,500-4,000 feet, especially along the Idaho and Montana border. The frontal band will push through KMSO from 21/1500-1800Z, with a 30% probability for ceilings and visibility to reach MVFR during rain showers. West-northwest winds will develop area wide behind the front this afternoon, with gusts of 20-25kts.

MSO WATCHES/WARNINGS/ADVISORIES

MT...Flood Watch through Sunday morning for Kootenai/Cabinet Region.

ID...None.