This data release contains SnowModel snow evolution simulation output on a 100-meter (m) geospatial grid for a 311 kilometer (km) × 300 km model domain in Colorado, United States, encompassing the Colorado and Gunnison River Basin headwaters in the Upper Colorado River Basin. Weather Research and Forecasting (WRF) Model convection-permitting and orography-resolving (4-km grid spacing) regional climate simulations provided the atmospheric forcing conditions to drive SnowModel in both a current and future climate scenario. A pair of continuous 13-water-year (2001-13) WRF model simulations was utilized: (1) a current climate control (CTL) simulation forced using ERA-Interim reanalysis, and (2) a future climate simulation using the pseudo-global-warming (PGW) method that uses the ERA-Interim reanalysis for the same period as (1) and adds an ensemble mean climate delta from 100 years in the future for the most extreme Representative Concentration Pathway (RCP) 8.5 scenario. The six SnowModel simulated outputs provided separately as child items in this data release include (1) air temperature (tair), (2) precipitation (prec), (3) precipitation amount falling as snow (spre), (4) snow water equivalent (swed), (5) liquid water supplied to the soil-snow interface from snowmelt (smlt), and (6) liquid water supplied to the soil-snow or soil-air interface either from snowmelt or rainfall (roff). The simulations used to produce these outputs were conducted on a 100-m geospatial grid. Land cover information (file vege.asc) for the simulation was provided by the 2010 North American Land Change Monitoring System and elevation information (file topo.asc) was provided by the U.S. Geological Survey National Elevation Dataset.

This data release contains SnowModel snow evolution simulation output on a 100-meter (m) geospatial grid for a 311 kilometer (km) × 300 km model domain in Colorado, United States, encompassing the Colorado and Gunnison River Basin headwaters in the Upper Colorado River Basin. Weather Research and Forecasting (WRF) Model convection-permitting and orography-resolving (4-km grid spacing) regional climate simulations provided the atmospheric forcing conditions to drive SnowModel in both a current and future climate scenario. A pair of continuous 13-water-year (2001-13) WRF model simulations was utilized: (1) a current climate control (CTL) simulation forced using ERA-Interim reanalysis, and (2) a future climate simulation using the pseudo-global-warming (PGW) method that uses the ERA-Interim reanalysis for the same period as (1) and adds an ensemble mean climate delta from 100 years in the future for the most extreme Representative Concentration Pathway (RCP) 8.5 scenario. The six SnowModel simulated outputs provided separately as child items in this data release include (1) air temperature (tair), (2) precipitation (prec), (3) precipitation amount falling as snow (spre), (4) snow water equivalent (swed), (5) liquid water supplied to the soil-snow interface from snowmelt (smlt), and (6) liquid water supplied to the soil-snow or soil-air interface either from snowmelt or rainfall (roff). The simulations used to produce these outputs were conducted on a 100-m geospatial grid. Land cover information (file vege.asc) for the simulation was provided by the 2010 North American Land Change Monitoring System and elevation information (file topo.asc) was provided by the U.S. Geological Survey National Elevation Dataset.

This data release contains SnowModel snow evolution simulation output from water years 2022 to 2023 (October 1, 2021, through September 30, 2023) on a 100-meter (m) geospatial grid for a 3 kilometer (km) × 2 km model domain near Coal Creek off Coal Bank Pass in the San Juan Mountains in southwest Colorado, USA. The three quantities simulated for this release were snow water equivalent for the standard model configuration (swe_standard), snow water equivalent for an open canopy model configuration (swe_open), and incoming shortwave radiation for the open canopy model configuration (qsin_open). The simulation used to produce these outputs was forced using meteorology from the National Land Data Assimilation System (NLDAS-2). Land cover information for the standard simulation was provided by the North American Land Change Monitoring System and land cover for the open canopy model configuration was set to the grassland land cover type. Elevation information was provided by the U.S. Geological Survey (USGS) National Elevation Dataset. This research was funded by the Department of the Interior South Central Climate Adaptation Science Center.

This data release supports the study by Sexstone and others (2020) and contains simulation output from SnowModel (Liston and Elder, 2006), a well-validated process-based snow modeling system. Simulations are for water years 1984 through 2017 (October 1, 1983 through September 30, 2017) across a 11,200 square kilometer model domain in the San Juan Mountains of southwestern Colorado, United States that encompasses the Rio Grande Basin headwaters (HUC8 13010001). This data release also contains supporting field-based snow and meteorological station observations collected within the model domain during water years 2016 and 2017 that were used to evaluate SnowModel simulations. Sexstone and others (2020) provide details and summarize findings from the SnowModel simulations and supporting observations. SnowModel simulation output provided in this data release are stored in NetCDF files that have spatial (100-meter [m] grid resolution) and temporal (yearly) dimensions. Simulated SnowModel annual snow metrics (water years 1984 through 2017) in the attached NetCDF files include: mean winter (1 October to 31 May) air temperature (T; degrees Celsius [°C]), cumulative winter precipitation (P; millimeters [mm]), peak snow water equivalent (SWE; mm), SWE:P (ratio of peak SWE to winter P; m/m), snow-covered days (days with snow on the ground; days), total snowmelt (surface-water input into the soil that occurs when SWE greater than [>] 0; mm), snowmelt rate (rate the snow melts from peak SWE to melt out; millimeter per day [mm/day]), SM50 (water year day following peak SWE when half of snowpack has melted), peak SWE timing (water year day when peak SWE occurs), melt-out timing (water year day when snow melt out occurs), sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm), sublimation:P (total snow sublimation to winter P ratio; m/m), 1 March SWE (mm), 1 April SWE (mm), 1 May SWE (mm), and 1 June SWE (mm). Supporting observations are provided in this data release in comma separated value (csv) files. Supporting meteorological station observations from three meteorological stations (daily mean values for the previous day) include: air temperature (°C), relative humidity (percent [%]), wind speed (meter per second [m/s]), incoming shortwave radiation (watts per meter squared [W m-2]), net radiation (W m-2), and albedo. Supporting field-based snow observations collected at 73 locations at a daily temporal dimension include: SWE (mm), standard deviation of SWE (mm), snow depth (m), and standard deviation of snow depth (m). An inventory and description of each of the files attached to the data release is provided below. Inventory of data release: URGB_SnowModel_study.xml: FGDC-compliant metadata file for the data release files. melt_doy.nc: NetCDF file of annual melt-out timing (water year day when snow melt out occurs) from SnowModel output . melt_rate.nc: NetCDF file of annual snowmelt rate (rate the snow melts from peak SWE to melt out; mm/day) from SnowModel output. peak_swe.nc: NetCDF file of annual peak SWE (mm) from SnowModel output. peak_swe_doy.nc: NetCDF file of annual peak SWE timing (water year day when peak SWE occurs) from SnowModel output. SM50.nc: NetCDF file of annual SM50 (water year day following peak SWE when half of snowpack has melted) from SnowModel output. snow_days.nc: NetCDF file of annual snow-covered days (days with snow on the ground) from SnowModel output. sub_p.nc: NetCDF file of annual sublimation:P (total snow sublimation to winter P ratio; m/m) from SnowModel output. sum_P_may.nc: NetCDF file of annual cumulative winter P (mm) from SnowModel output. sum_snow_RO.nc: NetCDF file of annual total snowmelt (surface-water input into the soil that occurs when SWE > 0; mm) from SnowModel output. sum_sub.nc: NetCDF file of annual sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm) from SnowModel output. swe_p.nc: NetCDF file of annual

This data release supports the study by Sexstone and others (2020) and contains simulation output from SnowModel (Liston and Elder, 2006), a well-validated process-based snow modeling system. Simulations are for water years 1984 through 2017 (October 1, 1983 through September 30, 2017) across a 11,200 square kilometer model domain in the San Juan Mountains of southwestern Colorado, United States that encompasses the Rio Grande Basin headwaters (HUC8 13010001). This data release also contains supporting field-based snow and meteorological station observations collected within the model domain during water years 2016 and 2017 that were used to evaluate SnowModel simulations. Sexstone and others (2020) provide details and summarize findings from the SnowModel simulations and supporting observations. SnowModel simulation output provided in this data release are stored in NetCDF files that have spatial (100-meter [m] grid resolution) and temporal (yearly) dimensions. Simulated SnowModel annual snow metrics (water years 1984 through 2017) in the attached NetCDF files include: mean winter (1 October to 31 May) air temperature (T; degrees Celsius [°C]), cumulative winter precipitation (P; millimeters [mm]), peak snow water equivalent (SWE; mm), SWE:P (ratio of peak SWE to winter P; m/m), snow-covered days (days with snow on the ground; days), total snowmelt (surface-water input into the soil that occurs when SWE greater than [>] 0; mm), snowmelt rate (rate the snow melts from peak SWE to melt out; millimeter per day [mm/day]), SM50 (water year day following peak SWE when half of snowpack has melted), peak SWE timing (water year day when peak SWE occurs), melt-out timing (water year day when snow melt out occurs), sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm), sublimation:P (total snow sublimation to winter P ratio; m/m), 1 March SWE (mm), 1 April SWE (mm), 1 May SWE (mm), and 1 June SWE (mm). Supporting observations are provided in this data release in comma separated value (csv) files. Supporting meteorological station observations from three meteorological stations (daily mean values for the previous day) include: air temperature (°C), relative humidity (percent [%]), wind speed (meter per second [m/s]), incoming shortwave radiation (watts per meter squared [W m-2]), net radiation (W m-2), and albedo. Supporting field-based snow observations collected at 73 locations at a daily temporal dimension include: SWE (mm), standard deviation of SWE (mm), snow depth (m), and standard deviation of snow depth (m). An inventory and description of each of the files attached to the data release is provided below. Inventory of data release: URGB_SnowModel_study.xml: FGDC-compliant metadata file for the data release files. melt_doy.nc: NetCDF file of annual melt-out timing (water year day when snow melt out occurs) from SnowModel output . melt_rate.nc: NetCDF file of annual snowmelt rate (rate the snow melts from peak SWE to melt out; mm/day) from SnowModel output. peak_swe.nc: NetCDF file of annual peak SWE (mm) from SnowModel output. peak_swe_doy.nc: NetCDF file of annual peak SWE timing (water year day when peak SWE occurs) from SnowModel output. SM50.nc: NetCDF file of annual SM50 (water year day following peak SWE when half of snowpack has melted) from SnowModel output. snow_days.nc: NetCDF file of annual snow-covered days (days with snow on the ground) from SnowModel output. sub_p.nc: NetCDF file of annual sublimation:P (total snow sublimation to winter P ratio; m/m) from SnowModel output. sum_P_may.nc: NetCDF file of annual cumulative winter P (mm) from SnowModel output. sum_snow_RO.nc: NetCDF file of annual total snowmelt (surface-water input into the soil that occurs when SWE > 0; mm) from SnowModel output. sum_sub.nc: NetCDF file of annual sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm) from SnowModel output. swe_p.nc: NetCDF file of annual

This data release supports the study by Sexstone and others (2020) and contains simulation output from SnowModel (Liston and Elder, 2006), a well-validated process-based snow modeling system. Simulations are for water years 1984 through 2017 (October 1, 1983 through September 30, 2017) across a 11,200 square kilometer model domain in the San Juan Mountains of southwestern Colorado, United States that encompasses the Rio Grande Basin headwaters (HUC8 13010001). This data release also contains supporting field-based snow and meteorological station observations collected within the model domain during water years 2016 and 2017 that were used to evaluate SnowModel simulations. Sexstone and others (2020) provide details and summarize findings from the SnowModel simulations and supporting observations. SnowModel simulation output provided in this data release are stored in NetCDF files that have spatial (100-meter [m] grid resolution) and temporal (yearly) dimensions. Simulated SnowModel annual snow metrics (water years 1984 through 2017) in the attached NetCDF files include: mean winter (1 October to 31 May) air temperature (T; degrees Celsius [°C]), cumulative winter precipitation (P; millimeters [mm]), peak snow water equivalent (SWE; mm), SWE:P (ratio of peak SWE to winter P; m/m), snow-covered days (days with snow on the ground; days), total snowmelt (surface-water input into the soil that occurs when SWE greater than [>] 0; mm), snowmelt rate (rate the snow melts from peak SWE to melt out; millimeter per day [mm/day]), SM50 (water year day following peak SWE when half of snowpack has melted), peak SWE timing (water year day when peak SWE occurs), melt-out timing (water year day when snow melt out occurs), sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm), sublimation:P (total snow sublimation to winter P ratio; m/m), 1 March SWE (mm), 1 April SWE (mm), 1 May SWE (mm), and 1 June SWE (mm). Supporting observations are provided in this data release in comma separated value (csv) files. Supporting meteorological station observations from three meteorological stations (daily mean values for the previous day) include: air temperature (°C), relative humidity (percent [%]), wind speed (meter per second [m/s]), incoming shortwave radiation (watts per meter squared [W m-2]), net radiation (W m-2), and albedo. Supporting field-based snow observations collected at 73 locations at a daily temporal dimension include: SWE (mm), standard deviation of SWE (mm), snow depth (m), and standard deviation of snow depth (m). An inventory and description of each of the files attached to the data release is provided below. Inventory of data release: URGB_SnowModel_study.xml: FGDC-compliant metadata file for the data release files. melt_doy.nc: NetCDF file of annual melt-out timing (water year day when snow melt out occurs) from SnowModel output . melt_rate.nc: NetCDF file of annual snowmelt rate (rate the snow melts from peak SWE to melt out; mm/day) from SnowModel output. peak_swe.nc: NetCDF file of annual peak SWE (mm) from SnowModel output. peak_swe_doy.nc: NetCDF file of annual peak SWE timing (water year day when peak SWE occurs) from SnowModel output. SM50.nc: NetCDF file of annual SM50 (water year day following peak SWE when half of snowpack has melted) from SnowModel output. snow_days.nc: NetCDF file of annual snow-covered days (days with snow on the ground) from SnowModel output. sub_p.nc: NetCDF file of annual sublimation:P (total snow sublimation to winter P ratio; m/m) from SnowModel output. sum_P_may.nc: NetCDF file of annual cumulative winter P (mm) from SnowModel output. sum_snow_RO.nc: NetCDF file of annual total snowmelt (surface-water input into the soil that occurs when SWE > 0; mm) from SnowModel output. sum_sub.nc: NetCDF file of annual sublimation (total snow sublimation including surface, canopy, and blowing snow components; mm) from SnowModel output. swe_p.nc: NetCDF file of annual

This data release contains historical SnowModel (Liston and Elder, 2006) output for the Crown of the Continent and surrounding areas in Montana, USA; and Alberta and British Columbia, Canada from September 1, 1981 through August 31, 2020. Fifteen daily variables were simulated or derived for this release: (1) snow water equivalent (swed), (2) liquid precipitation (rpre), (3) solid precipitation (spre), (4) albedo (albd), (5) glacial ice melt (glmt), (6) total precipitation (prec), (7) runoff (roff), (8) snow covered area (sca), (9) snow density (sden), (10) snowmelt (smlt), (11) snow depth (snod), (12) snow sublimation (ssub), (13) air temperature (tair), (14) wind speed (wspd), and (15) wind direction (wdir). The simulation used to produce these outputs was conducted on a 30 m geospatial grid and was forced using meteorology from a recently completed (2023) 4 kilometer reanalysis product using the Weather Research and Forecasting (WRF) model covering the conterminous United States (CONUS404, Rasmussen and others, 2023a; 2023b). Land cover information for the simulation was provided by the 2016 National Land Cover Database (Jin and others, 2019) and 30 m elevation information was provided by the National Elevation Dataset (Gesch and others, 2018).

This data release contains historical SnowModel (Liston and Elder, 2006) output for the Crown of the Continent and surrounding areas in Montana, USA; and Alberta and British Columbia, Canada from September 1, 1981 through August 31, 2020. Fifteen daily variables were simulated or derived for this release: (1) snow water equivalent (swed), (2) liquid precipitation (rpre), (3) solid precipitation (spre), (4) albedo (albd), (5) glacial ice melt (glmt), (6) total precipitation (prec), (7) runoff (roff), (8) snow covered area (sca), (9) snow density (sden), (10) snowmelt (smlt), (11) snow depth (snod), (12) snow sublimation (ssub), (13) air temperature (tair), (14) wind speed (wspd), and (15) wind direction (wdir). The simulation used to produce these outputs was conducted on a 30 m geospatial grid and was forced using meteorology from a recently completed (2023) 4 kilometer reanalysis product using the Weather Research and Forecasting (WRF) model covering the conterminous United States (CONUS404, Rasmussen and others, 2023a; 2023b). Land cover information for the simulation was provided by the 2016 National Land Cover Database (Jin and others, 2019) and 30 m elevation information was provided by the National Elevation Dataset (Gesch and others, 2018).

This data release contains historical SnowModel (Liston and Elder, 2006) output for the Crown of the Continent and surrounding areas in Montana and Idaho, USA; and Alberta and British Columbia, Canada from September 1, 1981 through August 31, 2020. Fifteen daily variables were simulated or derived for this release: (1) snow water equivalent (swed), (2) liquid precipitation (rpre), (3) solid precipitation (spre), (4) albedo (albd), (5) glacial ice melt (glmt), (6) total precipitation (prec), (7) runoff (roff), (8) snow covered area (sca), (9) snow density (sden), (10) snowmelt (smlt), (11) snow depth (snod), (12) snow sublimation (ssub), (13) air temperature (tair), (14) wind speed (wspd), and (15) wind direction (wdir). Daily variables were also summarized to monthly means or sums, and daily swed was also summarized to annual peak swed. Monthly summaries were further summarized to U.S. Geological Survey 12-digit Hydrologic Units. The simulation used to produce these outputs was conducted on a 90 m geospatial grid and was forced using meteorology from a recently completed (2023) 4 kilometer reanalysis product using the Weather Research and Forecasting (WRF) model covering the conterminous United States (CONUS404, Rasmussen and others, 2023a; 2023b). Land cover information for the simulation was provided by the 2016 National Land Cover Database (Jin and others, 2019) and 90 m elevation information was provided by the National Elevation Dataset (Gesch and others, 2018).

This data release contains historical SnowModel (Liston and Elder, 2006) output for the Crown of the Continent and surrounding areas in Montana and Idaho, USA; and Alberta and British Columbia, Canada from September 1, 1981 through August 31, 2020. Fifteen daily variables were simulated or derived for this release: (1) snow water equivalent (swed), (2) liquid precipitation (rpre), (3) solid precipitation (spre), (4) albedo (albd), (5) glacial ice melt (glmt), (6) total precipitation (prec), (7) runoff (roff), (8) snow covered area (sca), (9) snow density (sden), (10) snowmelt (smlt), (11) snow depth (snod), (12) snow sublimation (ssub), (13) air temperature (tair), (14) wind speed (wspd), and (15) wind direction (wdir). Daily variables were also summarized to monthly means or sums, and daily swed was also summarized to annual peak swed. Monthly summaries were further summarized to U.S. Geological Survey 12-digit Hydrologic Units. The simulation used to produce these outputs was conducted on a 90 m geospatial grid and was forced using meteorology from a recently completed (2023) 4 kilometer reanalysis product using the Weather Research and Forecasting (WRF) model covering the conterminous United States (CONUS404, Rasmussen and others, 2023a; 2023b). Land cover information for the simulation was provided by the 2016 National Land Cover Database (Jin and others, 2019) and 90 m elevation information was provided by the National Elevation Dataset (Gesch and others, 2018).