An anticyclone is a weather phenomenon defined as a large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere as viewed from above. Effects of surface-based anticyclones include clearing skies as well as cooler, drier air. Fog can also form overnight within a region of higher pressure.
An anticyclone just below Southern Australia near Tasmania.
Hadley cell circulation tends to create anticyclonic patterns in the Horse latitudes, depositing drier air and contributing to the world's great deserts.
The subtropical ridge shows up as a large area of black (dryness) on this water vapor satellite image from September 2000.
Golden Gate Bridge in fog
Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere, the troposphere, just below the stratosphere. Weather refers to day-to-day temperature, precipitation, and other atmospheric conditions, whereas climate is the term for the averaging of atmospheric conditions over longer periods of time. When used without qualification, "weather" is generally understood to mean the weather of Earth.
Cumulonimbus cloud surrounded by stratocumulus
New Orleans, Louisiana, after being struck by Hurricane Katrina. Katrina was a Category 3 hurricane when it struck although it had been a category 5 hurricane in the Gulf of Mexico.
Jupiter's Great Red Spot in February 1979, photographed by the uncrewed Voyager 1 NASA space probe.
Aurora Borealis