A low pressure system will develop Saturday night across southwest
Montana, but model guidance shows considerable uncertainty. A
slower, stronger system could produce heavy snowfall in localized
areas, while a weaker or faster-moving low would limit accumulations.
* WHAT…Heavy snow possible. Chance of moderate impacts is 80
percent, and major impacts from snow is at least 50 percent.
There is a 35 percent chance that Georgetown Lake, Anaconda,
Butte, and Homestake Pass could receive greater than 4 inches.
There is a 10 percent chance that snowfall could exceed 10 inches
from Georgetown Lake to Homestake Pass. Northern Granite and
Powell counties have a lower probability of significant snowfall,
except MacDonald Pass has a 25 percent chance of exceeding 4
inches.
* WHERE…Interstate 90 between Warm Springs and Homestake Pass
including Butte, Georgetown Lake, and Highway 12 Elliston to
MacDonald Pass.
* WHEN…From late Saturday night through Sunday morning.
* IMPACTS…Roads, and especially bridges and overpasses, could
become slick and hazardous. The weight of snow on tree limbs may
impact power lines and could cause sporadic power outages. For
MODERATE impacts from snow, expect disruptions to normal
activities. Hazardous traveling conditions. Use extra caution
while driving. Closures and disruptions to infrastructure may
occur. For MAJOR impacts from snow, expect considerable
disruptions to normal activities. Dangerous or impossible
traveling conditions. Avoid travel in the impacted areas if
possible. Widespread closures and disruptions to infrastructure
may occur.
* ADDITIONAL DETAILS…Winds: Northerly winds between 10 and 20 mph
are possible Saturday night and could worsen road conditions and
reduce visibility further in the falling snow.