What aspect of wildfire behavior is influenced by changes in weather conditions?

Changes in weather conditions significantly impact fire spread rates and intensity. Weather factors such as temperature, humidity, wind speed, and precipitation are critical in determining how a wildfire behaves. For instance, higher temperatures and lower humidity levels can increase the flammability of fuels, causing fires to spread more rapidly and intensively. Wind can carry embers to new locations, which can also lead to increased rates of spread.

The initial ignition points are important, but they are not solely influenced by weather; they can also depend on human activity, natural causes, or fuel availability. Likewise, while weather conditions affect firefighting efforts, they don't directly dictate how long those efforts will last. The effectiveness of fire retardants is also influenced by weather, but more so by the conditions during application and the characteristics of the fire rather than the overall behavior changes that occur in response to varying weather. Thus, fire spread rates and intensity is the aspect directly tied to changes in weather, making it the primary focus in understanding wildfire behavior.