Mark Johnson's exclusive winter forecast

CLEVELAND - THE PLAYERS: Winter 2010-11 will be a battle between opposite ocean patterns. First, there is La Nina. La Nina is the COOLING of the Pacific Ocean waters near the equator. Currently, we are experiencing the strongest La Nina since 1955! Water temperatures are already between 3 & 3.5 degrees F below normal along the equator. Strong La Ninas tend to bring slightly above normal precipitation to the area along with several weeks of warmer than normal temperatures.

But, La Nina is NOT the only player in this year's winter forecast. Our winter weather is greatly affected by a pressure pattern known as the North Atlantic Oscillation (NAO). This is the pressure difference between a semi-permanent low pressure over Greenland and high pressure near the Azores in the central Atlantic. Weaker low pressure over Greenland tends to draw much colder air down from Canada across the Great Lakes and Northeast. Ohio's weather is colder than normal! This is the NEGATIVE PHASE of the NAO. So far, the low pressure is weak. The NAO is in its negative phase and October in Ohio has been cooler than normal. What's more, fewer sunspots and solar flares tend to re-enforce the negative NAO.  I expect the negative phase of the North Atlantic Oscillation to stay strong for most of the winter season.

ROUND 1: The North Atlantic Oscillation should dominate at least the first half of winter. I expect December to average 1 to 2 degrees F BELOW normal. Precipitation should be mainly snow and average above normal for the month. Lake Effect snows should kick in by early to mid-month.

ROUND 2: January looks to be colder than normal, but not as cold on average as December. I would look for temperatures to average between 0 and 1 degree F below normal. Snowfall will average near to above normal and come from the occasional Alberta Clipper, Lake Effect snow shower, or Rocky Mountain Low.

ROUND 3: In February, our strong La Nina in the Pacific Ocean will bump temperatures up above normal for several days or a week at a time. On average, look for temperatures to be above normal for the month by a degree or so. Although we may get a break from Lake Effect snow and the Alberta Clippers, keep an eye out for a Panhandle Hook snow storm to affect the Ohio Valley or Lower Great Lakes during the month. I do believe snow totals here will average below normal for the month.

THE DECISION: Winter temperatures for December through January (Climatological Winter) will likely average near to slightly below normal in most spots across Northern Ohio. Winter snowfall will be near to slightly above average, in total. Winter will come in waves. Days or weeks of cold and snow being followed by days or weeks of mild and tranquil.