VSmoke-Web is a web-based implementation of VSmoke (Lavdas, 1996) and is designed to assist with planning prescribed burns in the Southern United States. VSmoke is a simple gaussian smoke dispersion model that calculates isopleths of surface smoke concentration. Output from the model represents peak hourly concentrations of PM2.5 or visibility (under development). Contour values and their colors correspond to the PM 2.5 thresholds for the Air Quality Index (AQI) and reflect potential health impacts ranging from moderate to hazardous (Visit AirNow for mode AQI info). Burn location can be set by clicking on the map or by entering the Latitude and Longitude. Note that the Latitude and Longitude should be entered in decimal degrees (30.38,-84.37) or degrees+decimal minutes (30 22.80, -84 22.20 - note the space between degree and minute values).