What Makes Weather Change?

Weather is the combination of sunlight, wind, rain, snow and temperature in the atmosphere at any given time. The amount of sunlight creates major weather patterns on Earth. 

Areas near the equator receive direct sunlight all year long. This intense heat produces wet tropical climates. The sun shines at an angle on middle latitudes, bringing warmer summers and cooler, drier winters. Frigid polar regions get little direct sunlight, making them cold year-round.  

The movement of air between warm and cold areas also determines weather. As air warms near the tropics, it rises and flows toward the poles. Colder, denser air then cycles back towards lower latitudes setting up wind patterns. 

When air masses with different temperatures meet, storms often erupt, bringing rain or snow.  

Tracking sunlight patterns and air circulation helps meteorologists forecast weather and measure climate trends over seasons, years or decades in areas across the globe. 

Learning about these major mechanisms allows us to explain and even predict weather shifts where we live.