During an October 31 site visit to USGS streamgage on the Allagash River, Maine, hydrologic technician Laura Flight took this photo of pancake ice, also known as pan ice, collecting in an eddy on the shore of the Allagash River.

The formation of ice on the rivers monitored by the USGS causes a change in the stage-discharge relationship we rely on, so we document ice conditions whenever possible. On the Allagash, we typically see backwater from ice in the last couple weeks of November. Credit: Laura Flight, USGS. Original public domain image from Flickr