Temperature is a weather variable that measures how warm or cold the air is at a given location and time. In Technosylva products, temperature is used with wind, relative humidity, precipitation, and fuel moisture to characterize the fire environment and support wildfire behavior and risk modeling.
Why Temperature Matters for Wildfire
Temperature influences how quickly fuels dry and how readily they ignite. Higher air temperatures increase evaporation from vegetation, litter, and duff, reducing fuel moisture and making fuels more receptive to ignition. Temperature also interacts with relative humidity: when temperatures rise and RH drops, fine fuels can dry rapidly and support faster fire spread.
Temperature alone does not determine fire behavior, but it is an important part of the weather conditions that shape ignition potential, flame length, rate of spread, and suppression difficulty. The most concerning wildfire conditions occur when high temperatures coincide with low RH, strong winds, and critically dry fuels.
How to Interpret Temperature
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Cool temperatures: Fuels generally retain more moisture, especially when RH is also high. Ignition potential and spread rates are typically lower, although wind and fuel conditions can still support fire activity.
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Warm temperatures: Fine fuels dry more quickly, particularly during extended dry periods. Fire activity becomes more likely when warm temperatures combine with low RH and receptive fuels.
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Hot temperatures: Fuels can reach critically low moisture levels more quickly. When paired with low RH and wind, hot conditions can support rapid fire growth, higher flame lengths, and more difficult suppression.
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Temperature/RH crossover: Temperature/RH crossover may be used as an operational field heuristic for elevated fire activity when the air temperature in °C is greater than or equal to the RH percentage (such as 30°C and 30% RH).
Temperature in Technosylva Products
In Wildfire Analyst (WFA), temperature is delivered as a forecasted weather variable across the forecast horizon. It is used directly in fire behavior modeling and as an input to derived fire danger and fuel moisture metrics.
Temperature is also an input to metrics and models such as Fire Potential Index Composite (FPIC): Temperature influences the fuel moisture and fire activity components used to assess fire potential.