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    • Regional Snowfall Index (RSI)

    Metadata Updated: September 19, 2023

    The Regional Snowfall Index (RSI) is an index of significant snowstorms that impact the eastern two thirds of the U.S. The RSI ranks snowstorm impacts on a scale from 1 to 5, similar to the Fujita scale for tornadoes or the Saffir-Simpson scale for hurricanes. NCEI has analyzed and assigned RSI values to over 500 storms going as far back as 1900. New storms are added operationally. As such, RSI puts the regional impacts of snowstorms into a century-scale historical perspective. The RSI differs from other indices because it includes population. RSI is based on the spatial extent of the storm, the amount of snowfall, and the juxtaposition of these elements with population. The area and population are cumulative values above regional specific thresholds. For example, the thresholds for the Southeast are 2", 5", 10", and 15" of snowfall while the thresholds for the Northeast are 4", 10", 20", and 30" of snowfall. Population information ties the index to societal impacts. Currently, the index uses population based on the 2000 Census. The RSI is an evolution of the Northeast Snowfall Impact Scale (NESIS) which NCDC (the precursor to NCEI) began producing operationally in 2005. While NESIS was developed for storms that had a major impact in the Northeast, it includes the impact of snow on other regions as well. It can be thought of as a quasi-national index that is calibrated to Northeast snowstorms. By contrast, the RSI is a regional index; a separate index is produced for each of the six NCDC climate regions in the eastern two-thirds of the nation. The indices are calculated in a similar fashion to NESIS, but our experience has led us to propose a change in the methodology. The new indices require region-specific parameters and thresholds for the calculations. For details on how RSI is calculated, see Squires et al. 2011.

    Access & Use Information

    License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

    Downloads & Resources

    Dates

    Metadata Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) January 1, 2011 (publication), June 1, 2014 (revision)
    Frequency Of Update asNeeded

    Metadata Source

    Harvested from ncdc

    Other Data Resources

    Graphic Preview

    RSI map example for snowstorm events.

    Additional Metadata

    Resource Type Dataset
    Metadata Date June 23, 2023
    Metadata Created Date October 28, 2022
    Metadata Updated Date September 19, 2023
    Reference Date(s) January 1, 2011 (publication), June 1, 2014 (revision)
    Responsible Party DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce (Point of Contact)
    Contact Email
    Guid gov.noaa.ncdc:C00465
    Category Tag 16E15F51 D96E 4051 9124 75665Abdc6Ff ["Transportation","Physical Data"]
    Access Constraints Cite as: Squires, Michael F.; Lawrimore, Jay H. (2011): Regional Snowfall Index [indicate subset used]. NOAA National Centers for Environmental Information. https://doi.org/10.25921/r2cd-th81 [indicate access date], Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives., Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose.
    Bbox East Long -65.0
    Bbox North Lat 50.0
    Bbox South Lat 30.0
    Bbox West Long -100.0
    Coupled Resource
    Frequency Of Update asNeeded
    Graphic Preview Description RSI map example for snowstorm events.
    Graphic Preview File https://www.ncei.noaa.gov/pub/data/metadata/images/C00465_RSI-image.jpg
    Graphic Preview Type PNG
    Harvest Object Id 1e414772-7ed8-4b3a-8b95-084cf8e9e349
    Harvest Source Id 2cb3ef77-1683-4c2a-9119-dc65e50917c6
    Harvest Source Title ncdc
    Licence
    Lineage RSI values are a function of the area affected by the snowstorm, the amount of snow, and the number of people living in the path of the storm. For a full description of how the Index was calculated, please view the documentation.
    Metadata Language eng; USA
    Metadata Type geospatial
    Old Spatial {"type": "Polygon", "coordinates": [[[-100.0, 30.0], [-65.0, 30.0], [-65.0, 50.0], [-100.0, 50.0], [-100.0, 30.0]]]}
    Progress onGoing
    Spatial Data Service Type
    Spatial Reference System
    Spatial Harvester True
    Temporal Extent Begin 1900-01-01

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