Andrew observes a single high-pressure area with no fronts moving around it, so he concludes that this area will have clear weather.
- He also sees at least two colliding fronts. He notes that when the two fronts collide, the new front is created in a low-pressure system. This new front, represented on the map with a purple line, is a cold front.
- According to Andrew, this area will experience cooler temperatures, rain, and thunderstorms.
Note that High-pressure areas are linked with clear weather because they bring sinking air, which is warmer and drier than the surrounding air. This warming and drying of the air prevents cloud formation and precipitation.
Also, Cold fronts are associated with cooler temperatures, rain, and thunderstorms because they bring cold air that displaces the warmer air ahead of it. The warm air is forced to rise, which cools it and causes condensation, which in turn leads to cloud formation and precipitation.