Time-of-Day Analysis
Definition
A statistical tool in wildfire arson investigation that compares the time-of-report distribution for suspected arson fires against confirmed accidental fires in the same region, exploiting the empirical finding that intentional wildfire ignitions cluster in mid-morning to early afternoon on high-danger days.
- Compares
- Time-of-report for suspected arson vs confirmed accidental fires
- Scope
- Same region, wildfire ignitions
- Pattern exploited
- Intentional ignitions cluster mid-morning to early afternoon
- Condition
- Most useful on high-danger days
Common questions
Can time-of-day analysis alone prove a specific fire was arson?+
No. It is a statistical, population-level pattern used to support suspicion or prioritise investigative resources across a series of fires; it cannot establish that any single fire was intentionally set without corroborating scene and forensic evidence.
Why do intentional wildfire ignitions cluster mid-morning to early afternoon?+
That window tends to combine daylight access for the person setting the fire with the day's rising temperature and falling humidity, conditions that also make a fire easier to establish and spread once ignited.
Related terms
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- Heel of a Fire
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- Ignition-Point Clustering Analysis
- A spatial statistical analysis applied to a series of suspected wildfire arson incidents, examining whether the geographic distribution of identified ignition points...
- Multiple Origin Areas
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- Negative-Corpus Argument
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- Pour Pattern
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- Trailer Evidence
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- Undetermined Cause
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