This readme file describes the data associated with the journal article entitled “Accounting for groundwater in stream fish thermal habitat responses to climate change” published in the journal, Ecological Applications. The data is contained in a single Microsoft Excel file entitled “SnyderEtal_Data”. The file contains two individual worksheets: “SiteData” and “TemperatureData”. The “SiteData” worksheet describes the names and locations of sites where temperature data were collected. There are a total of 78 sites located on nine individual streams within Shenandoah National Park, Virginia. The worksheet consists of four fields (columns) described below: Field Name Description Site Number The number (arbitrary) assigned to individual stream reaches where temperature data was collected Stream name The name of the stream associated with each individual site number Longitude Longitude in decimal degrees of site location Latitude Latitude in decimal degrees of site location The “TemperatureData” worksheet contains daily mean air and water temperature data that forms the basis of primary inferences described in the article. The worksheet consists of five fields (columns) described below: Field Name Site Number Description The number (arbitrary) assigned to individual stream reaches where temperature data was collected. Date Sampling date for individual temperature measurements or predictions AirTemp_observed Air temperature in degrees Celsius observed for each site on each sampling date. Note, air temperature measurements were only collected at 27 of the 78 sites. AirTemp_Predicted Air temperature in degrees Celsius predicted for each site on each sampling date using multiple linear regression (see journal article for details). Air temperatures were predicted for all 78 sites. WaterTemp Water temperature in degrees Celsius observed for each site on each sampling date. Water temperature measurements were collected for all 78 sites.