To monitor the ice on the Great Lakes click here.
The weather patterns in the northern hemisphere typically come from west to east, leaving the great lakes with lake effect conditions on the south and eastern shores. All the great lakes encounter lake effect, clouds, rain and snow depending on the time of year and temperature.
Several "ingredients" are needed to create lake effect, below are some of the key components:
One: Fetch. The fetch is the length in which moist air travels along an open water lake. At least 80km.
Two: 13 degree temperature difference (in celsius). This is the temperature difference from the water to the 850mb level (5,000ft)
Three: Higher terrain/hills. This gives the moisture soaked air the lift it needs to produce clouds/snow/rain.
Another component is wind. 15-20kts is ideal for lake effect snow bands, lower winds allow other circulations to dominate and high winds can't organize lake effect. These are the basic requirements, a bit more has to take place in order to get prolonged lake effect events and heavy lake effect snow.
It usually takes the lake until early February to get the amount of ice it has on it right now but with the extreme cold we're experiencing it's ahead of schedule. Since lake Erie is about 95 percent ice covered and with well below average temperatures through next week, lake Erie will be nearly 100 percent covered in ice. An ice covered lake essentially acts like dry land, any polar/arctic air to move across it - doesn't pick up any moisture and in turn can't produce lake effect - no matter what the temperature difference is.