Increasing chances for ice jams with warmer temperatures in the forecast

Increasing chances for ice jams with warmer temperatures in the forecast
Posted at 6:08 PM, Jan 05, 2022
and last updated 2022-01-05 20:21:56-05

Flooding is not typically a major concern throughout the year in central Montana, however that does not mean it cannot happen. Many area rivers are already frozen over with countless days below freezing and even below zero throughout the last month. With temperatures expected to warm into the 30s and 40s next week, ice jams will pose more of a threat to riverfront properties.

As of right now, two ice jams have already resulted in minor flooding in Gallatin county. The first being the Gallatin River at Logan and the second being the Jefferson River near Three Forks. Now, the majority of the impact has been lowlands adjacent to the river. Flood Advisories remain in effect for these areas.

Temperatures are forecast to warm above freezing for several days next week. Any ice on area rivers will begin to melt, slowly allowing ice to flow more freely. Larger chunks of ice may become lodged in thin or curved areas of the river, acting as a makeshift dam.

While the river's flow becomes reduced, water begins to pile up upstream and flooding will ensue. At a certain point, the dam will no longer be able to hold up to the force of the water and it will break. This is where the real danger comes in as a rapid rush of water will push downstream with little or no warning. This is why its vital that those with a riverfront property be extremely vigilant heading into the next couple of weeks and throughout the rest of winter.

Remember, turn around don't drown. If you see water on a roadway, do not drive through it. Even if you are familiar with the area, it is possible the roadway beneath the water's surface has already washed away.