Winter

Winter starts at the Solstice when the sun is the farthest from the hemisphere on the earth making it the coldest time of year. 

In December, the northern hemisphere is tilted away from the sun and in June, the southern hemisphere is tilted away from the sun.

Northern Hemisphere Winter 

Regions include U.S., Central America, Canada, Europe, Asia and Northern Africa. Winter occurs on the December Solstice on or near December 21 

Southern Hemisphere Winter

Regions include Australia, New Zealand, South America and Southern Africa. Winter occurs on the June Solstice on or near June 21