Average monthly wind velocity
These maps show the average monthly wind velocity distribution across Australia.
Product code: IDCJCM0047
These maps show the average monthly wind velocity over Australia. The maps have been generated using data from the Bureaus MESOLaps_PT125 (MESOscale Limited Area Prediction System Point 125) model using the 00 UTC analysis and the 10 metre zonal (u) and meridional (v) wind components.
For example, 00 UTC would mean that for Perth(WST) this would be at 8:00am local time, but for Melbourne(EST) it would be 10:00am local time.
Wind velocity is a meteorological observation that includes both direction and speed. These maps show the average monthly wind speed and wind direction across Australia. Shading indicates wind speed, and the direction of arrows indicates direction the wind is blowing to. For example an arrow pointing upwards is blowing from the South to the North. Note that the size of the arrows is constant and does not represent wind speed.
From a large-scale perspective, wind direction and wind speed are produced by the rotation of the earth and large scale pressure differences. On a broad scale, Australia is dominated by westerlies in southern parts of the continent and easterlies (trade winds) in the northern parts. Seasonal variation in surface wind fields are due to movement of the Intertropical Convergence Zone (ITCZ) and the Subtropical Ridge (STR). During the southern hemisphere winter, when the sub tropical ridge is located further equatorward, a greater extent of the Australian continent is subject to westerly winds than in summer.
On regional and local scales wind speed and direction are affected by terrain, vegetation and meteorological factors such as the monsoon regime, tropical cyclones, sea/mountain breezes, frontal systems and convective activity. Given that the model resolution is 0.125 degrees (approximately 12.5km), very localised effects will not be fully resolved.
These maps are based on data processed by a computer model. Current conditions need to be accurately represented in the model (in the form of "analysis" fields) before the model can be used to forecast future weather. Analysis fields are created using data from the world's national meteorological services (from ground stations, upper air observations, satellites, ships, buoys). These data are fed into computers, checked for accuracy, and mapped onto a three-dimensional grid. It is these analysis fields which were used to develop the wind maps.
- About the maps - metadata and related information.