Beneath the ice on rivers, creeks and streams is flowing water.
Because of that flow, ice is never safe or stable to walk on, Pennsylvania Fish and Boat Commission Executive Director Tim Schaeffer said.
"It varies dramatically in thickness … and if you fall through the ice, you will be swept away underneath, and you will not make it out,” Schaeffer said.
"We've had an incredibly long cold snap, one that's been longer than a lot of us can recall, and it's made for great ice fishing on a lot of our lakes and our ponds," he added. "But this year, we've actually seen some of our flowing waters freeze over in a way that they haven't for a long time.”
Pennsylvania's major rivers are above 80% frozen, according to the National Weather Service (NWS).
"We echo the boat commission's safety recommendations, especially as temperatures gradually warm from the recent Arctic trend,” said Jim Brewster, a hydrologist with the National Weather Service.
Temperatures are expected to hit the mid-30s this weekend, according to NWS.
On thin ice
Ice depths are incredibly variable, Schaeffer said.
Commission staff recently were training first responders on the Susquehanna River in Northcentral Pennsylvania, he said. The ice on the river in that area was 18 inches thick.
To the south in Harrisburg, the ice was only an inch thick, he said.
The commission recommends that ice be at least four inches thick on lakes and ponds for ice fishing and other ice activities, he said.
"Winter won't last forever, and as those ice conditions ... start to deteriorate, you know, really use your best judgment," Schaeffer said.
"If you do go out on a lake or a pond for ice fishing or even just to take a walk, we remind people always wear a life jacket or a float coat that will give you some buoyancy if you would go through the ice — and never go out on the ice alone," he said.
Other ice safety tips from Schaeffer:
- New ice is stronger than old ice.
- Old ice will look grey or cloudy.
- Loud cracks or booms are signs that ice is deteriorating.
- Stay away from submerged objects that poke through the ice like trees, rocks, shrubs, embankments.
- Carry ice awls, which are handheld spikes that can help with a self-rescue.
"Even if it's shallow, you might not think it's a big deal, but you can drown and succumb to hypothermia in water that's not too deep," he said. "So it's best just to stay off of that ice on flowing waters at all costs.”
Schaeffer said once the ice is melted, life jackets must be worn while boating from Nov. 1 to April 30.
"Since we've had that cold water life jacket requirement in place little over 10 years now, we've seen the fatalities in those cold weather months be cut in half,” he said.
No jams yet
During winter freeze-thaw cycles ice builds up and creates dams on rivers, creeks and streams.
That can cause major flooding once weather becomes warmer. The last significant jam on the Susquehanna River was in 2018.
Brewster said NWS is unaware of any actively flooding ice jams across Northeast Pennsylvania.
“While a slight warmup is expected this week, temperatures will remain below the ice melting threshold, and we do not anticipate major liquid storms or river rises sufficient to break up the ice in the near future,” he said.
