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Any forecaster will happily tell you, computers make drawing a weather map a snap! Reading a weather map has become a lot easier, too.

Weather maps have been around for the better part of two centuries, and for much of that time, they were the only way to visualize a lot of what was going on — or what forecasters thought was going on — in the atmosphere. But even now, when satellite images of actual storms and fronts are available, often a television forecaster and a newspaper weather page will display a simplified weather map to make clear to viewers and readers what’s going on.

The typical stripped-down version of a weather map highlights a few features of the weather picture across the nation. As Figure 2-2 illustrates, centers of high pressure and low pressure are designated simply by a large “H” or “L” on the map. Cold fronts lead with arrows ahead of them and warm fronts with semicircles along their leading edge. Areas of precipitation are often designated with hatch-marks or shaded sections. Some temperature readings often are included, and occasional arrows will point out the directions of surface winds. Chapter 3 goes into more detail about these weather features.

FIGURE 2-2: A typical weather map showing features and symbols that are common to most simplified maps used in televised forecasts today.