Thursday is Ice Jam Awareness Day. The National Weather Service says Montana has the highest number of ice jams reported in the lower 48 states. While there are many kinds of ice jams, they happen when ice collects and prevents water from getting downstream. Water collects behind the natural dam causing flooding upstream
NWS Officials say 2/3 of the ice jams reported in Montana happen in February and March, but we're already seeing them this year. "We typically start our ice jam season in December, but in a cold winter they can be noted as early as November," said Gina Loss, NWS Hydrologist. Montana also has the highest number of ice jam related deaths in the lower 48.