The GFAs are a set of web-based displays covering the CONUS from the surface up to 42,000 feet mean sea level. Wind, icing, and turbulence forecasts are available in 3,000-foot increments from the surface to 18,000 feet and in 6,000-foot increments between 18,000 feet and 42,000 feet. Turbulence forecasts are also broken into low (below 18,000 feet) and high (above 18,000 feet) graphics. A maximum icing graphic and maximum wind velocity graphic are also available. Data is time-synchronized and available hourly from 14 hours prior, to 15 hours after a selected time. Data for each category is determined by the time period: observations (current time and the prior 14 hours) and forecasts (valid up to 15 hours in the future).