DETROIT, Dec. 29 (UPI) -- Wet weather could raise Great Lakes water levels up from last year, but the gains could evaporate because of unseasonably warm weather, U.S. experts say.
The U.S. Army Corps of Engineers released its six-month forecast Wednesday calling for above-average levels on the Lake Erie and Lake Ontario, The Detroit News reported.
All five Great Lakes are above water levels from last December, the corps said, although the larger lakes including Superior, Michigan and Huron are below their long-term water level averages.
Some fear that gains from the region's second-wettest year in 131 years could be offset because it's almost January and the lakes still lack much ice, as temperatures in December were 3.6 degrees above average.
"This time last year, there were several inches of snow on the ground and we had ice on the lakes," corps meteorologist Keith Kompoltowicz said. "We haven't seen a December like we would have liked to see in Detroit, and I think that sentiment is echoed across the Great Lakes."
Ice slows evaporation of lake water because it takes additional heat energy to melt the ice before it can evaporate the liquid beneath.
Water levels are a factor in everything from how much weight cargo ships can carry to how fast algae grows and fish spawn, and when recreational boaters can launch their vessels, the News said.