An area is considered to have high barometric pressure when it has greater atmospheric pressure than the surrounding area. Normal barometric pressure is between 980 millibars and 1,050 millibars. High pressure systems are also referred to as anticyclones.Know More
High pressure systems move in a clockwise motion in the Northern Hemisphere and counterclockwise in the Southern Hemisphere because of the Coriolis effect. The Coriolis effect is a result of Earth's rotation.
Low barometric pressure describes an area that has lower pressure than the surrounding area. Low pressure systems often bring high winds and warm air, leading to precipitation, clouds and potentially severe storms.Learn more about Weather Forecasts
In the United States, Hurricane Ivan impacted the area along the Gulf of Mexico, including Alabama, Florida, Louisiana and Texas. The effects of Hurricane Ivan reached as far north as Virginia and the Delaware River. Hurricanes: Science and Society indicates that Ivan finally dissipated over Texas.Full Answer >
The amount of sunlight striking an area, the geographic location of an area, the air pressure surrounding an area and the amount of water in the atmosphere all influence the local weather. Each of these components interacts with the other components, and they may exacerbate or moderate each other.Full Answer >
According to About.com, areas of low pressure within the Earth's atmosphere are caused by unequal heating across the surface and the pressure gradient force. Incoming solar radiation largely concentrates at the equator, resulting in warmer air at the lower latitudes. This warm air has a lower barometric pressure than the cooler, denser air near the poles, and the differences between these types of air create the pressure gradient force.Full Answer >
Temperature affects air pressure by causing the air to either become more or less dense, which expands or lowers its pressure. Warm air is less dense than cold air, and as air becomes less dense, its pressure increases.Full Answer >