A Red Flag Warning is a forecast product issued by a weather service when a defined combination of conditions is expected to occur within roughly the next day: typically sustained wind or frequent gusts above a threshold, relative humidity below a threshold, and dry fuels, all persisting for a minimum number of hours; the thresholds are set locally, and dry lightning can trigger one on its own. A Fire Weather Watch is the same assertion at longer lead and lower confidence. Three things the warning does not say are worth stating plainly: it does not say a fire exists, it does not say where one would start, and its thresholds are regional, so warnings are not comparable between areas. What it does say is that if an ignition occurs during the window, spread will be rapid and control difficult. The confusion this resolves is reading a warning as a prediction of fire. After this Concept you can state exactly which claim a Red Flag Warning makes and which claims it deliberately does not.
In fire weather forecasting, a red flag warning is a forecast product issued when meteorological conditions — strong, gusty winds combined with very dry fuels, or thunderstorms with little to no acco…