Posted: Jan 24, 2013 10:32 AM by Meteorologist Mike Heard
Updated: Jan 24, 2013 10:48 AM
Ice jams and ice formation in rivers and creeks can lead to flooding in western Montana starting as early as December. Freeze-up and break-up ice jams have been documented in the months of December, January and February.
Snowmelt and the breakup of river ice often occur in tandem. Ice jams respond to fluctuating river flows associated with snowmelt and, as a result, can intensify snowmelt flooding.
NOAA has a great web site full of information on ice jams at this link: River Ice Information and links