Spring-like temperatures are in the forecast on Friday, but a winter warm-up can lead to melting ice in waterways like the Susquehanna River.
Winds gusting as high as 35 miles per hour are also expected to cause areas of blowing and drifting snow.
Experts believe it will, most likely, dislodge the ice at some point in that timeframe.
To put that in perspective, in Harrisburg, 11 feet calls for action and 17 feet means flooding over the banks.
If you've been enjoying the especially robust January thaw that sent area temperatures into the 50s on Thursday, here's fair warning: Arctic-like winter is waiting in the wings for a return engagement, with a hazardous mix of freezing rain, sleet and snow predicted for Saturday.
Heavy rain is expected to move through Massachusetts Friday and persist into Saturday morning before a flash freeze triggered by dropping temperatures creates slick conditions on the roadways.
In much of northern and western Pennsylvania, upstate NY and northern New England, the rain will change to snow on Friday or Friday night, adding to the wintry mess.
"Will the Kennebec River come up? We have had ice jams before, sometimes with no problems, other times with big problems". "It's going to depend on a lot of things, how much rain we get, how warm it gets whether the ice moves", LaFlure added.
It's been a while since we had a serious ice jam flood in CT.
But first, a drenching, spring-style rainstorm is headed into the Berkshires, prompting a flood watch from the National Weather Service for Friday, extending into Saturday afternoon.
Also, due to recent very cold temperatures, rivers and streams across the area have rapidly accumulated ice cover and the possibility for flooding due to ice jams has increased substantially, Taylor said.
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