2023年2月24日 · Barometric pressure is measured either in millibars (mb) or inches of mercury (Hg). Readings below 29.80 Hg are often considered as low barometric pressure, whiles readings above 30.20 Hg are considered high; readings within the range of 29.9 Hg to 30.2 Hg are considered normal.

2024年9月12日 · When barometric pressure is high, the air is heavy and dense and stays close to the earth's surface, allowing the sun to shine. Low pressure allows the air to rise and form clouds, and produce rain, or snow if it is cold enough.

2018年3月13日 · Barometric pressure, an indicator of the weight of column of air, ranges from an historic high of 32.01 inches to an all-time low of 25.9 inches. Electronic barometers now are available in addition to older-style units that use a needle and dial to track pressure changes.

Simply put, a barometer acts like a balance that ‘balances' the weight of the atmosphere (or air around you) against the weight of a mercury column. If the air pressure is high, the mercury will rise. At low air pressure, the mercury goes down.

What is high or low barometric pressure? Adjusted to sea level, a pressure reading above 30.2 inHg is considered to be high pressure, and below 29.8 inHg is considered low.

2024年7月17日 · In high-pressure systems, the air sinks toward the Earth and warms upward, leading to dry and fair weather. In general, a mercury barometer can let you know if your immediate future will see clearing or stormy skies—or little change at all—based only on atmospheric pressure. Here is how to read a barometer and interpret barometric readings:

2024年2月27日 · The general rule of barometric pressure is simple: high pressure typically portends hot, dry weather while low pressure portends cool, damp weather. Here's why: High pressure means that the atmosphere is filled with heavy, dense air.

2023年9月21日 · High atmospheric pressure, typically associated with fair weather conditions, occurs when the air is denser due to the greater weight of air molecules above a given location. Low atmospheric pressure, on the other hand, is characterized by lighter air masses and is often associated with changing weather patterns, storms, or unstable conditions.

2019年7月3日 · A barometer is a widely used weather instrument that measures atmospheric pressure (also known as air pressure or barometric pressure) -- the weight of the air in the atmosphere. It is one of the basic sensors included in weather stations.

2022年7月3日 · Air pressure pushes down on the surface of the mercury, making some rise up the tube. The greater the air pressure, the higher the mercury rises. You can read the pressure off a scale marked onto the glass. At sea level, the atmosphere will push down on a pool of mercury and make it rise up in a tube to a height of approximately 760mm (roughly ...