This data release contains inputs for and outputs from hydrologic simulations for the Hawai‘i (HI) domain using the Precipitation Runoff Modeling System (PRMS) version 5.2.1.1 and the USGS National Hydrologic Model infrastructure (NHM, Regan and others, 2018). Historical simulations using the Daymet Version 4 gridded estimates of daily weather parameters (Thornton and others, 2020) were produced for the period 1980–2021. These data document the PRMS climate input data files for these simulations. Input files for the simulations include the PRMS parameter file and control file. The main landing page provides additional information and data dictionaries (parameters_data_dictionary.csv and control_data_dictionary.csv) that describe the parameter and control file values. Daymet forcings include precipitation and minimum and maximum temperature at a daily time-step. Available USGS measured streamflow data are included for 196 USGS streamgage locations from 1980–2021 (U.S. Geological Survey, 2022). CONTENTS OF THIS CHILD PAGE: 1. Precip.day = daily total precipitation climate-by-hydrologic response unit (CBH) file 2. Tmax.day = maximum daily temperature CBH file 3. Tmin.day = minimum daily temperature CBH file. 4. sf_data = daily measured USGS streamflow data 5. PRMS Version 5.2.1.1 = PRMS executable 6. HI_precalibration.param = PRMS parameter file for the HI domain precalibration release 7. HI_precalibration.control = PRMS control file for the HI domain precalibration release 8. HI_byHRU.param = PRMS parameter file for the HI domain byHRU release 9. HI_byHRU.control = PRMS control file for the HI domain byHRU release 10. HI_byPOIobs.param = PRMS parameter file for the HI domain byPOIobs release 11. HI_byPOIobs.control = PRMS control file for the HI domain byPOIobs release 12. HI_NHM_PRMS.bat = batch file that can be edited to run the model.

This data release contains 16 variables from the National Hydrologic Model Infrastructure with the Precipitation-Runoff Modeling System (NHM-PRMS) modeling application forced with Daymet version 4 (Rosa and others, 2025) from 1980 through 2021 that are summarized to a monthly time step and a twelve-digit hydrologic unit code for the spatial extent of Hawaii. The following fluxes and storages are included: total monthly precipitation, evapotranspiration, lateral flow, surface runoff, quickflow, interflow, recharge, groundwater flow, and the average monthly snow water equivalent, interflow storage, groundwater storage, total storage, and soil moisture. These data can be found in the “HI_huc12_monthly_nhmprms_daymet_1980_2021.nc” file. Additionally, two supplementary files are also included in this data release. The first file (“HI_weights_hru_to_huc12_nhmprms_daymet.csv”) contains the spatial weights or fraction that is used to “weight” the modeling output in the area-weighting process. The second file (“HI_summed_weights_per_huc12_nhmprms_daymet.csv”) contains the total fractional area within each twelve-digit hydrologic unit code that is covered by the modeling output and is important for filtering results in the data file (where a fractional coverage may be less than one). In the version 2.0 data release update, a new variable was added to the “HI_huc12_monthly_nhmprms_daymet_1980_2021.nc” file. Additionally, several new netCDF files were added that contain data summarizations from a different production run (output data referenced as "byPOIobs") within the model application data release by Rosa and others (2025). Two of the three files added contain daily estimates of soil moisture fraction ("HI_byPOIobs_huc12_daily_soil_moisture_fraction_nhmprms_daymet_1980_2021.nc") and daily estimates of snow water equivalent ("HI_byPOIobs_huc12_daily_pkwater_equiv_nhmprms_daymet_1980_2021.nc") at the twelve-digit hydrologic unit code spatial regions. The third file added contains monthly estimates of 16 variables from the "byPOIobs" modeling application production run ("HI_byPOIobs_huc12_monthly_nhmprms_daymet_1980_2021.nc"). See the file, “revision_history_nhmprms_daymet_PR.txt” for a full description of the revisions.

This metadata record documents a set of 116 comma delimited files and a data dictionary describing the inputs for the U.S. Geological Survey Precipitation Runoff Modeling System (PRMS) which is used to drive the National Hydrologic Model (NHM) for the Hawaiian domain. The National Hydrologic Model database contains parameters for hydrologic response units (HRUs) and stream segments needed to run the NHM. These parameters are generated using python scripts to process input datasets such as digital elevation models, soil maps, and land cover classifications. Many of the parameters were left at their default model value as they would need to be calibrated as part of the PRMS model development process. Please refer to the Supplemental Information and the Process Description elements of this metadata record for more details on the source datasets and scripts used to generate these parameters.

The U.S. Geological Survey (USGS), in cooperation with the State of Hawaiʻi Department of Transportation, estimated flood magnitudes for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEP) for unregulated streamgages in Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi, using data through water year 2020. Regression equations which can be used to estimate flood magnitude and associated frequency at ungaged streams were developed. The methods and results of the study are published in a separate report (https://doi.org/10.3133/sir20235014). This data release contains the tabular data that are listed as appendices (appendices A, B, and D) in the larger work: Magnitude and Frequency of Floods on Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi, State of Hawaiʻi, Based on Data through Water Year 2020.

The Geospatial Fabric is a dataset of spatial modeling units for use within the National Hydrologic Model that covers the conterminous United States (CONUS), Alaska, and most major river basins that flow in from Canada. This U.S. Geological Survey (USGS) data release consists of the geospatial fabric features and other related datasets created to expand the National Hydrologic Model to Hawaii. These datasets are found as child items to this landing page: 1) Data Layers for the Geospatial Fabric for National Hydrologic Modeling, Hawaii Domain, 2) GIS (Geographic Information Systems) Features of the Geospatial Fabric for National Hydrologic Modeling, Hawaii Domain, 3) Parameter Database for the National Hydrologic Modeling, Hawaii Domain, and 4) Topographic derivative datasets for the Geospatial Fabric for National Hydrologic Modeling, Hawaii Domain. See each item for more details.

This U.S. Geological Survey (USGS) data release record consists of topographic data themes that cover the Hawaiian Geospatial Fabric (HIGF) domain. The 30-meter (m) raster data sets included under Topographic Derivatives are: digital elevation (dem.tif) , topographic wetness index (TWI, twi.tif), slope (rise over run, slope.tif), aspect (asp.tif), flow accumulation (fac.tif), and flow direction (fdr.tif). All file formats are in GeoTIFF (Geographic Tagged Imaged Format).

The SWAT_Hanalei folder contains the input files needed to run the Soil & Water Assessment Tool (SWAT) model for the Hanalei watershed, the calibration data files, and a README_SWAT_Hanalei.txt document that describes the contents of this archive and how to run the model.

This data release contains inputs and outputs for hydrologic simulations of the conterminous United States (CONUS) using the National Hydrologic Model (NHM) application of the Precipitation Runoff Modeling System (PRMS) in ASCII and binary format and explanatory graphics in pdf format. These simulations were developed to provide estimates of water availability for historical conditions for the period October 1, 1980 to September 30, 2016 for five different calibration configurations; the first three years of the simulation should be considered the initialization period and should not be used for subsequent analysis. The five versions of model parameters and associated model output included in this data release are described in table 1 and in the Supplemental Information section of this metadata record. Table 2 provides information about the baseline datasets used for model calibration for each of the five parameter configurations. Figure 1 shows a schematic of the multi-step calibration procedure used to develop the model parameters. Table 3 describes the 36 model output variables that are included in the five attached folders. Five .tar folders are named according to the simulation configuration in table 1 and include the 36-model output variable files. Table 4 provides information about the 8,274 streamgage locations that are included in the NHM-PRMS. The NHM-PRMS parameter and control files for each of the five simulations are located on the child pages associated with this data release. The PRMS climate forcing input files for the simulations are in the DAYMET_CBH.zip folder. Summary files by streamgage of measured and simulated streamflow for the byHRU, byHRU_musk, and byHRU_musk_obs simulations are in the Streamgage_location_simulations_5999.zip folder. Any time series data in the model output files prior to the October 1, 1983 start date should be considered part of the model initialization period and should not be used. Please refer to the Supplemental Information element of this metadata record for more information about the model calibration, inputs, outputs, and summaries included in this data release.