USCG Meteorology Practice Exam

The majority of weather systems in North America predominantly move from west to east due to the prevailing atmospheric circulation patterns, particularly the westerlies. The westerlies are strong winds that occur in the mid-latitudes, which exert a significant influence on the movement of weather systems across the continent.

As these westerly winds dominate the middle latitudes, they help transport air masses, including high and low-pressure systems, as well as fronts, across North America. This west-to-east flow is most pronounced at the upper levels of the atmosphere, where the jet stream, a fast-flowing air current, assists in the movement of these systems.

Understanding this pattern is crucial for meteorological predictions, as it helps forecasters anticipate changes in weather, like the approach of storms, which typically travel along this trajectory. While there can be localized features or phenomena that cause deviations from this general movement, the overarching trend in North America remains the west-to-east progression of weather systems.