When the Northern Hemisphere is tilted towards the Sun, it experiences summer, while the Southern Hemisphere, being tilted away from the Sun, experiences winter. Thus, at this time, the Northern Hemisphere will be in summer, and the Southern Hemisphere will be in winter.
Conversely, when the Southern Hemisphere is tilted towards the Sun, it experiences summer, while the Northern Hemisphere experiences winter. This axial tilt is what causes the seasonal changes as the Earth revolves around the Sun.