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Hello everyone. You like weather dont you? But when you watch the news you see all these words like presure and ceiling and you do not have a clue what there talking about. Well here is a perfect guide to the six main things you need to know when your watching the weather and learning about it.

Wind

Wind is the horizontal movement of air in relation to the earth's surface. Wind direction tells where the wind is blowing from. For example, a "north wind" is coming from the north and is blowing towards the south. There are four components of wind that are measured: direction, speed, character (i.e. whether it's a gust or a squall) and shifts.

Gust

A sudden significant increase in, or rapid variation of wind speed. Usually a gust lasts less than twenty seconds.

Relative Humidity

Relative humidity is a percentage of water vapour per area at a specific temperature. Relative humidity is calculated at all times of the year, but the humidex is usually only given in the warmer months from May to September.

Relative humidity can be calculated using various methods and instruments. It is a calculation to find out how many grams of water vapour can be held at a given temperature. Usually, the warmer the air, the higher its capacity for holding water vapour. Each specific temperature has a holding limit for water, and the actual amount of water held in the air at the time of measurement can be represented as a percentage.

For example, if a parcel of air at 20ºC has a limit or capacity of 16 grams of water vapour and 16 grams of water vapour is measured, the air's holding capacity is at its maximum and the relative humidity (RH) of the air is said to be 100%. Take the same air with 8 grams of water vapour and your RH is 50%.

Dewpoint

The dewpoint is a measure of atmospheric moisture. It is the temperature at which air must be cooled in order to reach saturation (assuming that air pressure and moisture content are constant). As the surface of the earth cools at night, warm moist air near the ground is chilled and water vapour in the air condenses into droplets on the grass and other objects. Dew is particularly heavy on clear nights, when the earth cools rapidly. When a blanket of cloud insulates the earth, the cooling rate is slower. The greater the difference between the temperature and the dew point, the drier the air.

Pressure

The force per unit area exerted by the weight of the atmosphere above a point on or above the earth's surface. Also known as atmospheric pressure or barometric pressure.

Visibility

Visibility is defined as the greatest distance an object can be seen and identified. It is usually a visual estimate and is reported as prevailing visibility -- the maximum visibility common to one half or more of the horizon circle. When visibility is uniform in all directions, prevailing visibility and visibility are the same. When visibility is not uniform in all directions, you can determine prevailing visibility by dividing the horizon circle into sectors of visibility. Estimate the highest visibility common to one half or more of the horizon circle.

The maximum visibility on a clear day is 11 kilometres (7 miles), after which a flat ground horizon will fall away to a point that surface conditions cannot be observed. In order to report visibility beyond this distance visibility markers are used. These markers are measured and could include mountains/hills, tree lines and microwave towers. The visibility is determined by the weather observer at an airport or weather station. The observer reports how far away objects can be identified without obstruction.

Ceiling

Ceiling is a measurement primarily used by the aviation industry. The ceiling is the height of the lowest layer of broken or overcast clouds. Ceiling is reported in feet, which is the standard for the aviation industry.