A Colorful Story: Taking Stock of the Colors Used by the NWS in Public-Facing Forecast Products

Colors are a core part of risk communication from the weather enterprise: with the full rainbow used to display rainfall and severe weather on radar, air temperatures across a region, the likelihood of tropical storm force winds, and more. With their importance in mind, it is imperative that we understand how colors are currently used in forecast graphics produced by the National Weather Service (NWS), particularly by the National Centers for Environmental Protection (NCEP), the River Forecasting Centers, and local NWS Weather Forecast Offices. To address this knowledge gap, we created an inventory of graphics produced by the NWS and cataloged the ways in which these products use color along several different dimensions, including scale type (rainbow, monochromatic, etc.), colors used, color hex codes, hazard being communicated, colorblind friendliness, and more. Results from this cataloging highlight consistencies and inconsistencies in the use of color and trends in color use by the NWS. These findings are then put in the context of recommendations from literature ranging from risk communication theory to weather communication to graphic design and color theory. These findings indicate the extent to which current NWS products follow theory-based recommendations for color use and how colors can be used effectively in future products.