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Wildfires in Nagano Prefecture
Detected · VIIRS 375 m · Suomi NPP, NOAA-20, NOAA-21 · last 24 hours · updated 2026-10-11 09:22 UTC
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Fire history, 2012–2025
Detected · VIIRS S-NPP 375 m · 0.01° cells (~1.1 km) · complete years 2012–2025 · built 2026-09-23
Between 2012 and 2025, VIIRS detected fire in 281 km² of Nagano Prefecture at least once. In an average year it detected fire in 27 km², ranking 22nd of 47 regions of Japan.
Year by year
Detected area per year, km². Area of 0.01° cells with at least one detection in the year.
The busiest year was 2023, with 40 km² detected; the quietest was 2017, with 13 km². The 2021–2025 average is 27% higher than the 2012–2016 average.
Through the year
Share of all fire-days 2012–2025 by month. A fire-day is one cell with a detection on one day.
March, April and May together hold 52% of the fire-days in the record. The single busiest day was 30 March 2023, with detections in 8 cells.
Ground that burns again
Of the 281 km² with at least one detection, 8.5% had detections in three or more different years.
| Years with a detection | km² | Share |
|---|---|---|
| 1 year | 220 | 78% |
| 2 years | 37 | 13% |
| 3 to 5 years | 22 | 7.8% |
| 6 to 10 years | 2.0 | 0.7% |
| 11 years or more | 0.0 | 0.0% |
The half-degree square with the most fire-days is centred at 36.25, 138.25 and holds 24% of the region's fire-days.
The figures
Show the table
| Year | Detected km² | Fire-days |
|---|---|---|
| 2012 | 18 | 18 |
| 2013 | 39 | 40 |
| 2014 | 20 | 20 |
| 2015 | 24 | 25 |
| 2016 | 23 | 23 |
| 2017 | 13 | 13 |
| 2018 | 29 | 30 |
| 2019 | 39 | 40 |
| 2020 | 18 | 18 |
| 2021 | 36 | 36 |
| 2022 | 16 | 17 |
| 2023 | 40 | 40 |
| 2024 | 31 | 31 |
| 2025 | 35 | 35 |
Other regions of Japan
- Kumamoto Prefecture142 km² in an average year
- Fukuoka Prefecture100 km² in an average year
- Hokkaidō96 km² in an average year
- Aichi Prefecture94 km² in an average year
- Chiba Prefecture77 km² in an average year
- Ōita Prefecture72 km² in an average year
- How these figures are madeDetected area, cells, and the single-satellite record.
Detected area counts every 0.01° cell with at least one VIIRS detection, so a small fire counts as a whole cell and a fire missed by cloud or between passes is absent. Borders: Natural Earth 1:10m. 2012 begins on 20 January.