Developing analysis · Record 002
Chileno Fire,
Marin County.
A dated record of changing official figures, source disagreement and what can—and cannot—be concluded from the public incident record.
Editorial review: 24 September 2026 · Version 3
Latest reviewed snapshot
What is documented.
CAL FIRE’s active-incidents index reviewed on 24 September lists the Chileno Fire at 341 acres and 95% containment. It began on 20 September 2026 near Chileno Valley Road and Bordessa Road, west of Petaluma, in Marin County.
The incident detail page identifies Marin County Fire Department as the agency having jurisdiction.
The cause remains listed as under investigation. No public cause conclusion is stated in the reviewed CAL FIRE sources.
Evolution of knowledge
Two official views, different timestamps.
At review time, CAL FIRE’s index and its individual Chileno Fire detail page do not show the same incident figures. That difference is preserved here rather than silently choosing one and erasing the other.
Latest statewide summary reviewed on 22 September; the dedicated incident page remains an older snapshot.
Earlier snapshot on the dedicated page, last updated 20 September at 6:09 PM.
The most likely explanation is normal update lag between official publishing surfaces, but the source pages do not explicitly state the reason. Tecnobosque therefore records the discrepancy as a provenance issue, not as an error diagnosis.
Source chronology
How the public record changed.
CAL FIRE lists this as the start date and time.
Dedicated status update identifies the incident as active.
Latest timestamp still visible on the dedicated incident page at this review.
Statewide active-index snapshot preserved from Version 1.
Active-index snapshot preserved from Version 2.
Latest CAL FIRE active-incidents index value at editorial review.
Evidence discipline
What remains unknown.
- A reconciled official explanation for the difference between the incident index and detail page.
- A final technical cause finding.
- A complete timestamped perimeter sequence suitable for spatial growth analysis.
- Incident-specific weather observations aligned with each mapped growth interval.
- A final assessment of smoke exposure and downstream air-quality impacts.
Provenance
Sources and release.
- CAL FIRE — active incidents index ↗Source for the newer statewide summary values visible at review time.
- CAL FIRE — Chileno Fire incident page ↗Source for start time, location, jurisdiction, cause state and the earlier dedicated-page snapshot.
Version 1 · 21 September 2026: initial developing record, official-source comparison, chronology and evidence gaps.