The National Weather Service-Great Falls is forecasting a major winter storm this weekend in the region and has issued a winter storm watch for the entire region. Blizzard conditions are likely by Sunday morning over much of north-central Montana.
East side of Glacier Park region — small stream flood advisory: Periods of rain will continue to affect the east side of Glacier Park Friday. Rainfall of one to three inches has fallen in this region over the past two to three days. With an additional inch of rainfall possible, combined with snowmelt, some minor flooding on small streams and creeks is likely. Conditions will begin to slowly improve on Saturday evening, as colder air moves into the region and the rain changes to snow.
Entire region — Saturday afternoon into Sunday night: A strong area of low pressure will northeastward through eastern Montana on Saturday night into Sunday. With colder air moving southward from Canada into the region, rain will change to snow starting Saturday afternoon over the Rocky Mountain Front, and then on Saturday evening over the Plains and across southwest Montana. The snowfall could become heavy at times from Saturday evening through Sunday, with snowfall rates of 1 to 2 inches per hour.
Additionally, by Sunday morning, strong north winds are forecast to develop over northcentral Montana. The strong winds could create near blizzard conditions on Sunday over northcentral Montana. White-out conditions are possible on Sunday, making travel very difficult.
Total snow accumulations could exceed 10 inches over a large portion of northcentral Montana, while five to 10 inches of snowfall will be common over southwest Montana.
Even though snowfall amounts are forecast to be a bit lighter over southwest Montana, snowfall rates, combined with poor visibility will make travel difficult in this region at times.