Anticyclones are the regions of huge atmospheric pressure, which is relative to the air in the various surrounding regions.
These are known for the huge diameter that they have. They are also referred to the high-pressure systems. Anticyclones appear on all the weather charts in the form of concentric and spaced isobars.
The center of the anticyclones has characteristic patterns of circulation of air, with the subsiding air as well as the horizontal divergence of air towards the surface.
“Anticyclone” has been derived from the circular flow of the air within a system. Anticyclonic circulation is known to have local circulations, which is opposite to the rotation of the earth.
Light winds are known to circulate around the center of high pressure in clockwise directions towards the Northern Hemisphere and anticlockwise towards the Southern Hemisphere.
The air starts getting compressed as it is descending, which is responsible for adiabatic warming.
Here, the drier and warmer air suppresses the formation of clouds. This is why the anticyclones are associated with good weather in summer and cold and foggy weather during the winter season.
The temperate latitudes experience calm and settled weather after an anticyclone.
Anticyclones have slow and steady moving features. The mid-latitude anticyclones are divided into the cold and warm anticyclones. Subtropical anticyclones are generally warmer.
Weather Conditions During Anticyclones
Since anticyclones are associated with high pressure, they are responsible for bringing dry and unsettled weather, though it is mostly dependent on the weather of an area.
The cold anticyclones normally form over the polar regions. Since the temperature condition is extremely low here, the air is not only cold but also dense.
Inversions can develop at these low altitudes and anticyclones form, which, in turn, prevent the build-up of the clouds.
In this case, a cumulus cloud that has been growing since the daytime will stop immediately and will start spreading into a huge layer of stratocumulus clouds.
During the night when temperatures fall, freezing frosts do not form.
The warm anticyclones normally form over the areas of subtropical and tropical climates. Here the temperatures remain warm both at night and during the day.
This can also restrict the formation of clouds, and if at all clouds form, they will be broken into stratocumulus and cumulus clouds.
The anticyclone glooms are known to form when the air in a particular area is moist and warm and fog forms under calm and stable conditions.
Weather tends to remain in this manner until the sun burns it away. However, during the winter season, fog and low stratus can persist for many days and can even stay for weeks if the cases are extreme.
Few or little clouds characterize summer anticyclones. Cases, when there is no cloud cover, plus the sun is extremely strong, it will be sweltering during the day.
Light winds blow and cooling of the grounds at night can result in the morning mist.
Warm air rising from the ground is moist, and it can lead to heavy thunderstorms or hail storms.
Cloudless skies characterize the anticyclones during the winter season. Here, temperature drop stands responsible for making the nights cool and days warm. In addition, frost and fog form at night.
The systems of high pressure are known for the tiny pressure gradients, and the air pressure tends to change rapidly.
This, in turn, means that the winds will be gentle and comfortable. As soon as the air starts sinking, the areas warm up, which will lead to dry and warm weather.
Anticyclones are larger than the areas of depression, and they can produce long periods of settled and calm weather.
They are responsible for blocking the path of depression, and hence, slow down a bad weather condition. These are referred to as the Blocking Highs.
To wrap it up, areas of high pressure are capable of forming anywhere and anytime, and it can change the weather to a great extent.
In this case, the meteorologists or the weather forecasters are responsible for informing you about the changes in the weather conditions so that you can brace yourselves.