Low-pressure systems are associated with clouds and precipitation that minimize temperature changes throughout the day, whereas high-pressure systems normally associate with dry weather and mostly clear skies with larger diurnal temperature changes due to greater radiation at night and greater sunshine during the day.

The pressure of a given amount of gas is directly proportional to the temperature at a given volume. When the temperature of a system goes up, the pressure also goes up, and vice versa. The relationship between pressure and temperature of a gas is stated by the Gay-Lussac’s law.

Gay Lussac’s Law – states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature. If you heat a gas you give the molecules more energy so they move faster. This means more impacts on the walls of the container and an increase in the pressure.

Pressure is directly proportional to the temperature when the volume is held constant for a given amount of gas. It is also known as Gay-Lussac law.

The temperature of the gas is proportional to the average kinetic energy of its molecules. Faster moving particles will collide with the container walls more frequently and with greater force. This causes the force on the walls of the container to increase and so the pressure increases.

When it cools, it compresses. This directly affects the air pressure in your tires. For every increase of 10 degrees in temperature, your air pressure will increase by approximately 1 psi. Conversely, for every drop of 10 degrees in temperature, your air pressure will decrease by approximately 1 psi.

Pressure and Temperature. Air pressure depends on the weather conditions; it changes with altitude as well as with the rise and fall of temperature. The less the molecules of air are compressed, the lower the pressure. An area of low pressure occurs when the air pressure is lower with respect to its surroundings.

The most basic change in pressure is the twice daily rise and fall in due to the heating from the sun. Each day, around 4 a.m./p.m. the pressure is at its lowest and near its peak around 10 a.m./p.m. The magnitude of the daily cycle is greatest near the equator decreasing toward the poles.

High air pressure produces clear sky, dry and stable weather. In a low pressure zone, wind is circulated inwards and upwards rapidly. As a result, air rises and cools; clouds and precipitate are formed. Low air pressure produces unstable weather conditions like rain or storms.

The pressure exerted by air on all bodies at all times in all directions is called air pressure. When air moves at high speeds, it creates a low pressure area. The air inside a balloon exerts pressure in all directions, and makes it blow up. Air opposes the motion of a moving object.

1)The 3 main factors that affect barometric (air) pressure are:

• Temperature.
• Altitude or Elevation.
• Moisture ow water vapour.

In terms of climatology, high pressure forms at the horse latitudes, or torrid zone, between the latitudes of 20 and 40 degrees from the equator, as a result of air that has been uplifted at the equator.

A barometer reading of 30 inches (Hg) is considered normal. Strong high pressure could register as high as 30.70 inches, whereas low pressure associated with a hurricane can dip below 27.30 inches (Hurricane Andrew had a measured surface pressure of 27.23 just before its landfall in Miami Dade County).

Inch of mercury

As a general rule of thumb, lows have a pressure of around 1,000 millibars (29.54 inches of mercury).