How to Read a Wind Rose Meter
- 1). Determine what location the wind rose represents by reading the legend carefully. A wind rose will indicate statistics for only one location or region.
- 2). Note the time period represented by the wind rose. Determine if the graph presents an entire year's worth of data, one particular month over a period of years, or some other time period. This information is contained in the legend.
- 3). Understand that the typical orientation of a wind rose is with due North at the top. The bars on the wind rose point in radiating directions. If superimposed on the face of a compass, the bars usually pertain to winds coming out of the direction the bar points.
- 4). Relate the colors and thicknesses of the bars to the legend. The bars represent wind speed. Speed can be noted using meters per second, knots or miles per hour.
- 5). Notice that the labels on the concentric circles are percentages. A bar representing a wind speed of 15 miles per hour that reaches a circle with a label of 30 percent, for example, indicates that this wind speed happened 30 percent of the time represented by the graph. A shorter bar representing 20 miles per hour indicates that this wind speed occurred less than 30 percent of the time.
- 6). Identify the size of the empty circle in the middle of the diagram from which the bars radiate. This empty circle generally indicates periods of calm.
