Question

How does a falling barometer indicate bad weather is ahead?

Answer 1

Hint : Reading a barometer is very easy if we know what is indicated by different atmospheric pressure values. The difference in temperature of air creates wind and develops pressure systems. In general, if there is a drop in air pressure, we can say a storm is on the way, and then, the barometer gives low readings.

Complete Step-by-step solution:
A barometer is a tool which measures the atmospheric pressure and gives forecasts about how the weather is ahead. So, atmospheric pressure is also referred to as barometric pressure. An increasing value of barometer measurement indicates atmospheric pressure, and a falling measurement of a barometer indicates that the atmospheric pressure is decreasing.
Weather forecasters often refer to areas of high pressure or low pressure moving towards particular regions to describe the forecast conditions for those areas. As air rises in low pressure systems, it cools and often condenses into clouds and precipitation, leading to storms and rains. In high pressure systems, the air sinks towards the Earth and warms upwards, leading to dry and fair weather.
Normal pressure – If the barometer reading remains in between and in Hg, this is generally considered as normal, and it indicates that a steady weather is ahead.
High pressure – When a barometer gives a reading over inHg, this is considered as high, and high pressure indicates clear skies and pleasant weather.
Low pressure – when reading of the barometer is lower than inHg, this is considered as low air pressure, which is associated with warm air and rainstorm.
So, clearly, a falling barometer indicates bad weather is ahead.

Note:
How poorer the weather becomes is the difference between the high and low pressure system. The larger the difference, the larger the volatility is there within the atmosphere, and therefore the stronger the storms. The smaller the difference, the less seemingly we are to check rain or storms.