Jam sesh, bro. Image: NWS Burlington

This has been a winter of weird wonders. First it was snow in the Sahara. Then came ice balls on Lake Michigan. Now we’ve got to deal with ice jams.

Sub-zero temperatures last week didn’t just instantaneously turn boiling water to snow. They also quickly froze rivers, ponds and lakes across the Northeast and Midwest.

That’s been followed by what Capital Weather Gang aptly describes as a “brief and mildly disgusting warm-up” that’s softened all that ice with temperatures 10-20 degrees Fahrenheit above normal and rain. It’s also melted snow, which has run off into rivers and cracked up ice further.

And that, my friends, is a recipe for ice jams.

Wild roaming hordes of ice chunks from the size of baseballs to an average New York studio apartment have surged down waterways across the region. When these frozen flash floods meet with a bend in the river, a narrow strait, or a bridge, they can back up and overtop riverbanks with sometimes destructive results. Just how fast can ice pile up? The National Weather Service’s Burlington office shared what happened on the East Branch Ausable River in upstate New York over the course of three hours on Friday afternoon.

Total jam sesh.

This is what the the river gage looked like:

Major jam sesh. Image: U.S. Geological Survey

Ice jams are no joke, ya heard?

From New York to Pennsylvania to Ohio to Ontario (international ice!), fast-flowing ice jams have knocked trailers off their foundations, surrounded houses, and flooded basements. Thing will freeze back up early next week for most of the region, but if you happen to live near a river, be vigilant and ready to defend against marauding river ice. Here’s a sample of the ice jams rumbling on Friday: