A depression and an anticyclone are opposite atmospheric pressure systems that create different weather patterns. A depression (also called a low-pressure system or cyclone) has lower atmospheric pressure at its center, while an anticyclone has higher atmospheric pressure at its center.
In a depression, air rises because of the lower pressure, which causes cooling and condensation—producing clouds, rain, and often stormy weather. The rising air creates a partial vacuum that sucks surrounding air inward, which then spirals upward. In the Northern Hemisphere, this spiral moves counterclockwise; in the Southern Hemisphere, it moves clockwise.
In an anticyclone, air descends from above, which causes warming and drying. Descending air suppresses cloud formation, leading to clear skies and settled weather. The sinking air spreads outward at the surface, creating a clockwise spiral in the Northern Hemisphere and counterclockwise in the Southern Hemisphere.
Weather-wise, depressions bring unsettled conditions—wind, rain, and temperature changes. Anticyclones bring stable weather—sunshine, calm winds, and consistent temperatures. A typical depression might last a few days as it moves across a region, while anticyclones can remain stationary for longer periods, creating prolonged dry or wet spells depending on the season.
Understanding these systems is fundamental to weather forecasting, as they determine whether a location will experience wet or dry, mild or extreme conditions over coming days.