Full Range Urban Area Heat Anomalies - USA 2025

Notice: this is the latest Urban Area Heat Island Anomalies image service. This layer contains the relative degrees Fahrenheit difference between any given pixel and the mean heat value for the urban area in which it is located, for every city in the contiguous United States, Alaska, Hawaii, and Puerto Rico. The Heat Anomalies is also reclassified into a Heat Severity raster also published on this site. This 30-meter raster was derived from Landsat 8 imagery band 10 (ground-level thermal sensor) from the summer of 2025. It was developed by the Trust for Public Land’s Geospatial Team, which specializes in nationwide spatial analysis to help communities and governments strategically identify, prioritize, and deliver parks, trails, and conservation plans to support their park access, public health, and climate resilience goals. To explore other versions of the data, visit the links below: There are no other versions of this layer published Federal statistics over a 30-year period show extreme heat is the leading cause of weather-related deaths in the United States. Extreme heat exacerbated by urban heat islands can lead to increased respiratory difficulties, heat exhaustion, and heat stroke. These heat impacts significantly affect the most vulnerable—children, the elderly, and those with preexisting conditions. The purpose of this layer is to show where certain areas of urban areas are hotter or cooler than the average temperature for that same urban area as a whole. Please note that each value is calculated relative to the local average for the urban area it is in. This means that there will sometimes be discontinuities along urban area boundaries. TPL has also developed a version of the data which uses municipality boundaries to calculate local averages, rather than urban area boundaries, which may be helpful for more fine-grained analysis. However, note that this data therefore has a greater number of discontinuities along municipality boundaries. That version can be found here: City Anomalies. Trust for Public Land uses analyses like this to help communities identify priority areas for park creation, tree canopy expansion, and other nature-based solutions that reduce heat risk and improve public health. Learn more about TPL’s broader climate program. This dataset represents a snapshot in time. It will be updated yearly, but is static between updates. It does not take into account changes in heat during a single day, for example, from building shadows moving. The thermal readings detected by the Landsat 8 sensor are surface-level, whether that surface is the ground or the top of a building. Although there is strong correlation between surface temperature and air temperature, they are not the same. We believe that this is useful at the national level, and for cities that don’t have the ability to conduct their own hyper local temperature survey. Where local data is available, it may be more accurate than this dataset. Dataset Summary This dataset was developed using proprietary Python code developed at The Trust for Public Land, running on the EarthDaily (formerly Descartes Labs) platform through their Python API. The EarthDaily platform allows for extremely fast retrieval and processing of imagery, which makes it possible to produce heat island data for all cities in the United States in a relatively short amount of time. TPL’s Geospatial Team has more than 20 years of experience building national datasets, custom decision-support tools, and spatial analyses used by governments, nonprofits, and planners across the country. What can you do with this layer? This layer has query, identify, and export image services available. Since it is served as an image service, it is not necessary to download the data; the service itself is data that can be used directly in any Esri geoprocessing tool that accepts raster data as input. Common applications include stand-alone urban heat island analysis, park and green infrastructure planning, and public health risk assessment. In order to click on the image service and see the raw pixel values in a map viewer, you must be signed in to ArcGIS Online, then Enable Pop-Ups and Configure Pop-Ups. Using the Urban Heat Island (UHI) Image Services The data is made available as an ArcGIS Online hosted tiled image service layer. The service does not have a processing template and can be used directly in web maps, ArcGIS Pro or QGIS. The service returns actual pixel values so you can apply your own renderer to the imagery. Common applications include stand-alone urban heat island analysis, park and green infrastructure planning, and public health risk assessment. A typical operation at this point is to clip out your area of interest. To do this, add your polygon shapefile or feature class to the map view, and use the Clip Raster tool to export your area of interest as a geoTIFF raster (file extension ".tif"). In the environments tab for the Clip Raster tool, click the dropdown for "Extent" and select "Same as Layer:", and select the name of your polygon. If you then need to convert the output raster to a polygon shapefile or feature class, run the Raster to Polygon tool, and select "Value" as the field. Other Sources of Heat Island Information Please see these websites for valuable information on heat islands and to learn about exciting new heat island research being led by scientists across the country: EPA’s Heat Island Resource Center Dr. Ladd Keith, University of Arizona Dr. Ben McMahan, University of Arizona Dr. Jeremy Hoffman, Science Museum of Virginia Dr. Hunter Jones, NOAA Daphne Lundi, Senior Policy Advisor, NYC Mayor's Office of Recovery and Resiliency About the Trust for Public Land Geospatial Team Trust for Public Land’s planning and GIS (geographic information systems) service uses cutting-edge research, innovative mapping technologies, and groundbreaking planning practices to help communities and governments strategically identify, prioritize, and deliver parks, trails, and conservation plans. Their work spans national datasets, regional modeling, and community-scale decision support, with a focus on producing actionable, policy-relevant insights. Disclaimer/Feedback With nearly 2,600 urban areas represented, checking each urban areas's heat island raster for quality assurance would be prohibitively time-consuming, so The Trust for Public Land checked a statistically significant sample size for data quality. The sample passed all quality checks, with about 98.5% of the output cities error-free, but there could be instances where the user finds errors in the data. These errors will most likely take the form of a line of discontinuity where there is no city boundary; this type of error is caused by large temperature differences in two adjacent Landsat scenes, so the discontinuity occurs along scene boundaries (see figure below). Trust for Public Land would appreciate feedback on these errors so that future versions of the national UHI dataset can be improved. TPL also works with partners to refine and apply geospatial data for local planning and analysis. Contact [e-mail] with feedback.