Exploring California hotspots
Use the California preset to find recent satellite observations, then narrow the selection and check official incident information separately.
Start with the circle’s actual coverage
The California preset is a 650 km radius circle centered at 37.2, −119.7 (latitude, longitude in decimal degrees). It is not the California state boundary. Counts can include points outside California and should not be described as a statewide incident total.
Refine a question about a place
- Choose 6, 12 or 24 hours. These windows select observation acquisition times in UTC. Start with 24 hours for context, then try a shorter window to focus on more recent observations in the retrieved file. A smaller count alone does not establish that incident activity has decreased.
- Narrow the geography. Choose Custom area, enter the place’s latitude and longitude, and reduce the radius. The map’s pan and zoom controls change the view, not the selected search area.
- Inspect time and confidence. Select a point or use Inspect in the observation list. Read Observed at, coordinates, VIIRS confidence and any FRP value in MW. Confidence describes detection quality; it is not an incident severity rating.
- Check state and coverage before export. Note the fetched time, observation range and any snapshot, replay, stale-data or rejected-row label. Export shown CSV downloads the plotted subset, up to the newest 1,000 matching records, with source provenance. Keep those qualifications when sharing it.
The app uses one Suomi NPP VIIRS source file. Read how to interpret hotspot points and counts before comparing selections.
Cross-check official incident information
Open CAL FIRE’s official incident information separately and check the relevant incident’s location, dates and updates. A cluster of satellite detections is not an official incident record; several points can relate to one incident. The two sources should not be expected to have equal counts.
This explorer does not provide a complete incident or evacuation map. Missing detections do not establish safety. Follow the responsible local authorities for evacuation instructions.
Keep the original source in view
Compare the chosen observation times and sensor with the NASA FIRMS viewer. Check official downloads and current source notices if coverage or dates appear different.
Return to the California map or explore the distinct Brazil workflow.