The input datasets are daily precipitation and minimum and maximum temperature for a period of 64 years for warming scenarios of 0 degrees to 8 degrees Celsius, by 0.5-degree increments for the Squannacook River watershed in Massachusetts. The source of the data is the Stochastic Weather Generator (SWG; Steinschneider and Najibi, 2022) and includes 100 ensembles from the SWG. The daily time-series, space-delimited files cover three subwatersheds within the Squannacook River watershed in a format readable by the Precipitation Runoff-Modeling System (PRMS; https://www.usgs.gov/software/precipitation-runoff-modeling-system-prms). The input files were input to PRMS, along with the model control and parameter files, to generate the output files. The output files are daily time-series in comma-delimited format of the resulting discharges for the Squannacook River at the mouth of the river and at the Squannacook River near West Groton, Massachusetts streamgage for each of the ensembles of each of the warming scenarios.

The datasets are streamflow characteristics computed from the 1 million ensembles of the Stochastic Watershed Model for each warming scenario of 0 to 8 degrees Celsius in 0.5-degree intervals for the Squannacook River at West Groton, Massachusetts streamgage location. Each value in the files represents a streamflow characteristic computed from an ensemble that covers a period of 64 years of daily streamflows computed by the Stochastic Watershed Model. The Stochastic Watershed Model was developed at Tufts University (Shabestanipour and others, 2022). The streamflow characteristics include the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year recurrence interval of the annual maximum daily streamflow and the 7-day low flow with a 2- and 10-year recurrence interval. There is one file for each streamflow characteristic. Shabestanipour, G., Broudeur, Z., Farmer, W., Steinschneider, S., Vogel, R., and Lamontagne, J., 2022, Stochastic watershed model ensembles for long-range planning—Verification and validation: Water Resources Research, v. 59, no. 2, 20 p., accessed January 3, 2024 at https://doi.org/10.1029/2022WR032201.

The datasets are gridded daily precipitation and minimum and maximum temperature for a period of 64 years for warming scenarios of 0 to 8 degrees Celsius, by 0.5 degrees for the Nashua River watershed in Massachusetts. The data are output from a Stochastic Weather Generator developed at Cornell University (Steinschneider and Najibi, 2022) and includes 100 ensembles of each warming scenario. The data files are in NetCDF format (https://www.unidata.ucar.edu/software/netcdf/). Steinschneider, S., and Najibi, N., 2022, A weather-regime based stochastic weather generator for climate scenario development across Massachusetts—Technical documentation: Ithaca, N.Y., Cornell University, [Department of] Biological and Environmental Engineering report, 47 p., accessed February 16, 2023, at https://eea-nescaum-dataservices-assets-prd.s3.amazonaws.com/cms/GUIDELINES/FinalTechnicalDocumentation_WGEN_20220405.pdf

This data release provides a set of Hydrological Simulation Program--Fortran (HSPF) model files representing 5 EPA-selected future climate change scenarios for the Upper Charles River Basin in Massachusetts. Output from these models are intended for use as input to EPA Watershed Management Optimization Support Tool (WMOST) modeling. Climate scenarios, based on 2036-2065 changes from 1975-2004 for Representative Concentration Pathways (RCP) 4.5 and 8.5, model the effects of air temperature and precipitation changes (in degrees F for air temperature, in percent for precipitation) made to the input historical meteorological time series for 1975-2004. Meteorological data are from Boston Airport (Boston, MA), T.F. Green Airport (Providence, RI), and Worcester Regional Airport (Worcester, MA). Each set of climate scenario model files are derived from the original calibrated model files created by the Charles River Watershed Association to develop Total Maximum Daily Loads (TMDLs) for nutrients, and modified by USGS to support WMOST modeling (refer to Source Input fields in this metadata file).

This data release provides a set of Hydrological Simulation Program--Fortran (HSPF) model files representing 5 EPA-selected future climate change scenarios for each of three river basins: Blackstone in Massachusetts and Rhode Island, Pawcatuck in Rhode Island, and Ispwich in Massachusetts. Output from these models are intended for use as input to EPA Watershed Management Optimization Support Tool (WMOST) modeling. Climate scenarios, based on 2036-2065 change from 1975-2004 Representative Concentration Pathways (RCP) 4.5 and 8.5, model effects of air temperature and precipitation changes (in degrees F for air temperature, in percent for precipitation) made to the input historical meteorological time series 1975-2004. Blackstone meteorological data are from T.F. Green Airport (Providence) and Worcester Regional Airport (Worcester), Pawcatuck meteorological data are from T.F. Green Airport (Providence), and Ipswich meteorological data are from 30 local National Weather Service Stations (1975-1995) and Boston Logan Airport (1996-2004). Each set of climate scenario model files are derived from the original calibrated model files developed to support WMOST modeling (refer to Source Input fields in this metadata file).

This data release provides a set of Hydrological Simulation Program--Fortran (HSPF) model files representing 5 EPA-selected future climate change scenarios for each of two river basins: Taunton and Sudbury, in Massachusetts. Output from these models are intended for use as input to EPA Watershed Management Optimization Support Tool (WMOST) modeling. Climate scenarios, based on 2036-2065 change from 1975-2004 Representative Concentration Pathways (RCP) 4.5 and 8.5, model effects of air temperature and precipitation changes (in degrees F for air temperature, in percent for precipitation) made to the input historical meteorological time series 1975-2004. Taunton meteorological data is from T.F. Green Airport and the Sudbury meteorological data is from Worcester Regional Airport. Each set of climate scenario model files are derived from the original calibrated model files developed to support WMOST modeling (refer to Source Input fields in this metadata file).

This data release provides a set of Hydrological Simulation Program--Fortran (HSPF) model files representing five EPA-selected future climate change scenarios for the Farmington River Basin in Massachusetts and Connecticut. Output from these models are intended for use as input to EPA Watershed Management Optimization Support Tool (WMOST) modeling. Climate scenarios, based on 2036-2065 changes from 1975-2004 for Representative Concentration Pathways (RCP) 4.5 and 8.5, model the effects of air temperature and precipitation changes (in degrees F for air temperature, in percent for precipitation) made to the input historical meteorological time series for 1975-2004. Meteorological data are from the following climate stations in Connecticut: Hartford Airport, Burlington, and Norfolk. Each set of climate scenario model files are derived from the original calibrated model files created by EPA and the Connecticut Department of Energy and Environmental Protection Bureau of Water Management to evaluate nutrient sources and loadings to Long Island Sound and assessment of impacts of Best-Management Practices (BMP), and later extended by U.S. Geological Survey (USGS) to support WMOST modeling (refer to Source Input fields in this metadata file).

The U.S. Geological Survey in cooperation with the Federal Emergency Management Agency has conducted a study to evaluate potential changes to1-percent annual exceedance probability streamflows. The study was conducted using the Precipitation Runoff Modeling System (PRMS). Climate inputs to the model of temperature and precipitation were scaled to anticipated changes that could occur in 2030, 2050, and 2100 based on global climate models. The output from the models were used to characterize the 1-percent AEP streamflows for the years 2030, 2050, and 2100 and compare the results to baseline conditions, 1950-2015. The data include the model input and output and spatial data for model referencing. Scripts for processing PRMS output to obtain final results are also provided.

This data release contains the model input and output data, and supporting files, from hydrologic simulations of streamflow conditions in the upper Klamath River Basin using the Precipitation-Runoff Modeling System (PRMS). The model was calibrated for the portion of the basin draining into Upper Klamath Lake. It simulates daily streamflow, snow, solar radiation, evapotranspiration, surface-water, and groundwater processes within the basin. The model calibration period spanned water years 2000 through 2015, and the model validation period spanned water years 1984 through 1999. The model was calibrated and validated using measured streamflow, snowpack, evapotranspiration, and solar radiation data sets.

This model application data release provides the data processing and model code used to generate predictions of daily stream water temperature across the contiguous United States from 1979-2021. We used a recurrent graph convolutional network (RGCN) algorithm to make daily stream temperature predictions. Stream water temperature observations, along with forcing data consisting of daily meteorological information, a stream distance matrix, and static stream characteristics were used to predict daily stream temperature summaries (minimum, mean, and maximum) for 57,810 stream segments across the contiguous United States. This model application data release is organized as follows: • data_processing_code.zip contains the instructions and code needed to assemble inputs to the model. This directory contains a README.txt file that describes all major processing steps and outputs of this code. • model_code.zip contains code to process the outputs from data_processing_code.zip into model-ready data structures and implements the modeling algorithm. This directory contains a README.txt file that describes all model-ready input files, major processing steps, and an overview of the modeling steps. • national_temperature_metadata.xml describes the top-level files contained in this model application data release (model outputs and supporting reach-level metadata). • The model outputs are contained in a Parquet database, where chunks of data are stored in regional and subregional (HUC2 and HUC4) nested folders titled huc2={HUC2 ID}.zip}. Each HUC2 can be downloaded separately. • data_access_pattern.R gives an example of how to extract and use the stream temperature predictions in this data release. • reach_metadata.csv contains reach-level metadata that describes how the reach was used in the model (training or testing) and how the reach was classified (groundwater, atmospheric, reservoir, thermoelectric) for evaluation purposes. The methods and results from this modeling effort are described in: Diaz, J., Oliver, S.K., Gorski, G. 2025. Evaluation of daily stream temperature predictions across the contiguous United States using a spatiotemporal aware machine learning algorithm. Environmental Modelling & Software, https://doi.org/10.1016/j.envsoft.2025.106655.