HARRISVILLE - Northeast Michigan could experience below average snowfall this winter, while temperatures could be a little below normal early in the winter, turning somewhat milder in the second part of season, according to the National Weather Service.
The winter forecast become more accurate around October, once weather scientists get a feel for how El Nino and La Nina are shaping up in the Pacific off the coast of South America, Jeff Zoltowski, a meterologist with the National Weather Service in Gaylord, said.
Zoltowski and senior meterologist John Boris presented the forecast during a weather spotter training session Thursday at the emergency operations center on M-72 west of Harrisville.
Right now, the condition known as the Southern Oscillation is neutral and should continue for the next six months, they said.
"During neutral El Nino conditions in other years, there has been a fairly strong trend in northeastern Michigan of below average snowfall, especially in the second half of the winter," Zoltowski said. "For the temperature outlook, there is a strong trend for temperatures to be a little below normal early in the winter, with temperatures returning to somewhat milder in the second part of the winter."
In addition to El Nino conditions, the two also look at computer models, patterns, observations and scientific analysis.
"There are key things that could mess this up," Zoltowski said.
In Michigan, the biggest challenge is the Great Lakes. The heat and moisture they produce as well as the amount of ice covering them affects storm tracking, pressure patterns, wind direction and other variables.
Known as a lake effect, the condition destabilizes weather September through December.
This means a shift of 10 to 20 degrees in wind across Lake Superior can cause heavy snow to land in a spot different from the forecast, Boris said.
"There is no worse feeling in the world than slaving over a forecast for eight hours and then looking out the window when you go home and finding out you're wrong," he said.
"You blend," Zoltowski. "You decide you like one forecast, then you go in a completely different direction. The atmosphere is very complicated and we know there is a lot we don't understand yet."
Betsy Lehndorff can be reached via email at firstname.lastname@example.org or by phone at 358-5693. Follow Betsy on Twitter @bl_alpenanews.