This website provides access to a historical archive of SNODAS data products for Colorado water supply basins. Snow Data Assimilation System (SNODAS) data from the National Operational Hydrologic Remote Sensing Center (NOHRSC) are processed daily to calculate Snow Water Equivalent (SWE) and Snow Coverage statistics for water supply basins in Colorado. Snow Water Equivalent is the estimate of the depth of liquid water contained within the snowpack. Snow coverage is a percent of the basin land surface covered by snow (water bodies in the basin are ignored). The national SNODAS gridded dataset has been processed to provide data products for Colorado. Mean SWE is displayed in the map using a legend similar to the National Weather Service. The SNODAS Tools website provides access to an archive of daily products.
Development of the SNODAS Tools was funded by the Colorado Water Conservation Board. The tools were developed by the Open Water Foundation.
Project resources are available on the OWF SNODAS project website
This website is under development with a scheduled completion date of June 30, 2017. It is likely that changes in the site's functionality and access to data will occur until then.
Contact: Joe Busto, email@example.com
Steve Malers, firstname.lastname@example.org
Website version 1.0.6 (2017-04-24)
The national SNODAS data are available from the Snow Data Assimilation System (SNODAS) and can be viewed at National Operational Hydrologic Remote Sensing Center (NOHRSC). The SNODAS data are processed into statistical data products by the CDSS SNODAS Tools.
The output consists of comma-separated-value (CSV) files ByDate (basin data for each day) and ByBasin (historical period for each basin). Data files can be downloaded by accessing the following URL resources. The zip file contains a shapefile with daily statistics in the attribute table (attribute names have been truncated to adhere to shapefile limit).
Latest Date Example: http://projects.openwaterfoundation.org/owf-proj-co-cwcb-2016-snodas/prototype/SnowpackStatisticsByDate/SnowpackStatisticsByDate_LatestDate.csv
Latest Date Example: http://projects.openwaterfoundation.org/owf-proj-co-cwcb-2016-snodas/prototype/SnowpackStatisticsByDate/SnowpackStatisticsByDate_LatestDate.geojson
Latest Date Example: http://projects.openwaterfoundation.org/owf-proj-co-cwcb-2016-snodas/prototype/SnowpackStatisticsByDate/SnowpackStatisticsByDate_LatestDate.zip
http://projects.openwaterfoundation.org/owf-proj-co-cwcb-2016-snodas/prototype/json/CO_boundary.geojson (State of Colorado rectangular boundary)
json/SNODAS_CO_BasinBoundaries.geojson (basin boundaries, same as daily boundaries)
StaticData/SNODAS_CO_BasinBoundaries.zip (input basin boundary layer shapefile)
StaticData/Watershed_Connectivity_v3.xlsx (input basin connectivity for total basin calculations)
Refer to the SNODAS Tools User Manual and SNODAS Tools Developer Manual for more information.
SNODAS data are processed into data products using QGIS and Python software as follows:
A summary of the analysis steps are described in the SNODAS Tools User Manual. More detailed explanation is provided in the SNODAS Tools Developer Manual.