How to read Weather Maps

Master weather maps! Decode symbols, pressure, fronts, and winds to understand forecasts.

How to interpret a synoptic chart In this skills worksheet we will learn how to interpret weather maps chart. The main features of a weather map are: isobars high-pressure and low-pressure cells cold and warm fronts wind patterns areas of rainfall in the last 24hrs Isobars and air pressure Isobars are lines that join places of equal air pressure measured in hectopascals hPa.Isobars are generally drawn either 2 or 4 hecotpascals apart. Isobars show different air pressure across the map. Isobars show the pattern of air pressure around the cells. Air pressure is the weight of the air pressing down on the earth's surface. It varies from place to place and time to time. Variations in pressure is the cause of the changes in our weather. High Pressure (H) Numbers increase towards the middle. When air is cooled, it becomes heavier than the surrounding air and falls. This increases its weight on the earth causing high-pressure cells. Weather - fine, dry stable weather. Wind moves in an anti-clockwise direction. Low Pressure (L) Numbers decrease towards the middle. When air is warmed, it becomes lighter than the surrounding air and tends to rise reducing its weight on the earth's surface, resulting in the formation of low pressure cells. Weather - cloudy, rainy unstable weather. Wind moves in a clockwise direction. Differences in air pressure cause air to move. Falling air in a high-pressure cell causes air to flow outwards from the centre towards surrounding areas of lower pressure. Moving air causes wind - the type of air that moves over us influences our weather, when the air changes our weather changes. Air Pressure Air Masses that affect Australia Cold Fronts and Warm Fronts Cold air and warm air do not mix easily. When winds cause cool or cold air and warm air masses to come into contact there is often a very distinct boundary between them called a front. There are two main types of fronts - Cold Fronts and Warm Fronts Animation Summer and Winter Weather Maps in Australia Summer In summer typical weather patterns include: low pressure over most of Northern Australia (Wet Season) tropical cyclones in the north of Australia high pressure over southern Australia and fine warm settled weather. low pressure cells to the south causing occasional cold fronts that bring storms on hot sunny days. Winter In winter, typical weather maps include: high pressure that has moved north to cover most of Australia bringing fine settled weather to the north. a belt of low pressure over the south of the continent bringing cool to cold weather occasional very cold southerly streams of air from the Southern Ocean. Using the weather maps above identify all the features of a weather map that you can see - Using the weather map above write a weather report for the each of the states for the next 24hrs. Use the following map to answer the questions below. Which TWO urban areas experienced rainfall in the previous 24 hours? Sydney and Cairns Hobart and Adelaide Port Hedland and Cairns Alice Springs and Darwin What is the approximate latitude and longitude of Perth? 32°S 116°E 32°N 111°E 34°S 124°E 28°S 130°W Which of the following weather conditions are likely to be experienced in PortHedland within the next 24 hours? Increasing rainfall and wind speed Decreasing rainfall and temperature Increasing temperature and decreasing rainfall Increasing temperature and decreasing wind speed What is the approximate speed and direction of the wind at Alice Springs? 1–5 km South West 1–5 km North East 6–10 km South West 6–10 km North East Which instrument is used to measure air pressure? Barometer Clinometer Compass Thermometer Which instrument below measures humidity?