This product uses the Federal Emergency Management Agency’s National Risk Index dataset API or downloadable datasets but is not endorsed by FEMA. The Federal Government or FEMA cannot vouch for the data or analyses derived from these data after the data have been retrieved from the Agency's website(s).
National Risk Index Counties (ArcGIS Feature Service): https://services.arcgis.com/XG15cJAlne2vxtgt/arcgis/rest/services/National_Risk_Index_Counties/FeatureServer/0
FEMA National Risk Index data are retrieved from that service when you look up an address.
Data provided by NOAA IBTrACS (International Best Track Archive for Climate Stewardship), accessed when you look up an address from https://www.ncei.noaa.gov/products/international-best-track-archive
Seasonal tropical cyclone impact probabilities are from Colorado State University when a county forecast is available, from https://tropical.colostate.edu/TC_impact.html .
Historical tornado paths (1950–2024) match FEMA’s Resilience Analysis and Planning Tool layer, sourced from NOAA Storm Prediction Center SVRGIS; see https://www.spc.noaa.gov/wcm/ and FEMA RAPT .
Flood zones are from the FEMA National Flood Hazard Layer, from https://www.fema.gov/flood-maps/national-flood-hazard-layer .
Nearby rivers, streams, lakes, and reservoirs are from the USGS National Hydrography Dataset, from https://www.usgs.gov/national-hydrography/national-hydrography-dataset .
Named flood sources and Map-view tiles include data from OpenStreetMap, © OpenStreetMap contributors, https://www.openstreetmap.org/copyright .
Satellite map view uses Esri World Imagery. See Esri’s data attributions at https://www.esri.com/en-us/legal/terms/data-attributions . Elevation uses USGS 3DEP lidar hillshade, elevation color from Mapzen Terrain Tiles on AWS Open Data, and National Hydrography Dataset streams, rivers, and lakes.
1% annual-chance 1-hour rainfall intensity is from NOAA Atlas 14, from https://hdsc.nws.noaa.gov/pfds/ .
Height Above Nearest Drainage in the contiguous U.S. is from the National Flood Interoperability Experiment CONUS HAND rasters (Oak Ridge National Laboratory), from https://web.corral.tacc.utexas.edu/nfiedata/ . Elsewhere it is from the Alaska Satellite Facility Global HAND dataset, produced from the Copernicus WorldDEM-30 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018, from https://gis.asf.alaska.edu/arcgis/rest/services/GlobalHAND/GLO30_HAND/ImageServer .
Hydrologic soil groups are from the USDA NRCS Soil Survey Geographic Database (SSURGO), from https://www.nrcs.usda.gov/resources/data-and-reports/soil-survey-geographic-database-ssurgo .
Historic wildfire perimeters are from NIFC Interagency Fire Perimeter History, from https://data-nifc.opendata.arcgis.com/datasets/nifc::interagencyfireperimeterhistory-all-years-view .
Recent wildfire perimeters are from WFIGS Interagency Fire Perimeters, from https://data-nifc.opendata.arcgis.com/datasets/nifc::wfigs-interagency-fire-perimeters .
Nearby fuel treatments are from USDA Forest Service FACTS Hazardous Fuel Treatment Reduction polygons, from https://apps.fs.usda.gov/arcx/rest/services/EDW/EDW_HazardousFuelsTreatments_01/MapServer/15 . Prescribed-fire perimeters from the NIFC and WFIGS layers above are included in that 2-mile search.
Structure wildfire risk, annual burn probability, and Community Wildfire Risk Reduction Zones are from USDA Forest Service Wildfire Risk to Communities landscape-wide risk rasters (2nd ed.), cataloged as RDS-2020-0016-2 (https://doi.org/10.2737/RDS-2020-0016-2 ). Overview: https://www.wildfirerisk.org/ . How to cite: Scott, Joe H.; Dillon, Gregory K.; Jaffe, Melissa R.; Vogler, Kevin C.; Olszewski, Julia H.; Callahan, Michael N.; Karau, Eva C.; Lazarz, Mitchell T.; Short, Karen C.; Riley, Karin L.; Finney, Mark A.; Grenfell, Isaac C. 2024. Wildfire Risk to Communities: Spatial datasets of landscape-wide wildfire risk components for the United States. 2nd Edition. Fort Collins, CO: Forest Service Research Data Archive.
California Fire Hazard Severity Zones are from CAL FIRE, from https://osfm.fire.ca.gov/what-we-do/community-wildfire-preparedness-and-mitigation/fire-hazard-severity-zones .
Red-flag warning counts are from the Iowa Environmental Mesonet VTEC archive, from https://mesonet.agron.iastate.edu/ .
Basic wind speed is from the ASCE 7 Hazard Tool, from https://ascehazardtool.org/ .
Peak ground acceleration is from the USGS National Seismic Hazard Model, from https://earthquake.usgs.gov/nshmp/ .
Tropical weather outlook graphics and tropical cyclone public advisories are from the NOAA National Hurricane Center, from https://www.nhc.noaa.gov/ .
Hurricane storm surge exposure is from the National Hurricane Center National Storm Surge Risk Maps (SLOSH Maximum of Maximums inundation at high tide, above ground), from https://www.nhc.noaa.gov/nationalsurge/ .