Undersized Fire Mapping Project

Undersized Fire Mapping Project (UFMP) consistently maps the location, extent and severity of selected small fires occurring in the United States from 1984 to present. These fires do not meet the minimum size requirements of at least 500 acres for the eastern states and Puerto Rico and 1,000 acres for the western states, Hawaii, and Alaska for the Monitoring Trends in Burn Severity (MTBS) Program and do not occur on National Park Service (NPS) lands. Provided data are only available for fires mapped to meet other Department of Interior and Forest Service objectives within specific temporal and spatial extents. NPS small fires are available on the Burn Severity Portal. The UFMP and NPS burn extent and severity products are published to augment the data that are available from the MTBS Program and shared with the user community on the Burn Severity Portal. These data products complement the temporally and spatially comprehensive data provided by the MTBS Program and help support a variety of policy and resource management information needs.

Like MTBS protocols, pre- and post-fire imagery are selected to match the assessment approach based upon landscape/vegetation type. Please review the Mapping Methods | MTBS page for details on this mapping approach.


1 - 12 months after fire containment

Learn More about Home | MTBS


Data Available



The Undersized Fire Mapping Project serves four primary user groups

  1. Field management units
  2. National and regional offices
  3. Existing databases from other comparable scaled programs
  4. Research and academic entities interested in fire severity

Mapping Method

Mapping Method

Burn Severity layers are created by first calculating spectral indices from pre- and post-fire satellite imagery that are sensitive to changes caused by fire. The two images are then subtracted showing the difference between them which is then thresholded into burn severity classes.


  • Pre- and post-fire satellite imagery
  • Burn area boundary shapefile
  • Differenced Normalized Burn Ratio (dNBR) and Relativized dNBR (continuous)
  • 6-class thematic thresholded dNBR
  • Metadata
  • Visualization products