Across the continental United States, the BlueSky Smoke Modeling Framework provides hourly forest fire emissions forecasts and calculates the concentrations of hazardous compounds 72 hours in advance. Though a traditional computational model itself, the BlueSky Framework pulls together the results from a number of different independent models for fire and fuel information, combustion of fuel, and speciated emissions calculations to produce its operational forecasts of fire-related emissions and smoke dispersals. One aspect of forest fire emissions that is of particular concern is small particulate matter, particularly microscopic particles with diameters less than 2.5 micrometers. These particles, known as PM2.5, are small enough to penetrate lung tissue and cause serious health problems in high concentrations. To assess the skill of the BlueSky Gateway, a system that uses the BlueSky Framework and the Community MultiScale Air Quality (CMAQ) model to forecast PM2.5 surface concentrations, Strand et al. compared the modeled estimates for two Californian forest wildfire events against observations.