What are the 3 main factors that affect climate?

Altitude

Temperatures decrease with height. The air is less dense and cannot hold heat as easily.

Winds

If winds are warm - they have been blown from a hot area - they will raise temperatures. If winds have been blown from cold areas they will lower temperatures.

Distance from the sea (continentality)

Land heats and cools faster than the sea. Therefore coastal areas have a lower temperature range than those areas inland. On the coast winters are mild and summers are cool. In inland areas temperatures are high in the summer and cold in the winter.

Aspect

Slopes facing the sun are warmer than those that are not. Thus south facing slopes in the northern hemisphere are usually warm. However, slopes facing north in the southern hemisphere are warmest.