Hydrologic Conditions MapperHydrologic Conditions Mapper
  •   July 2025 Hydrologic Conditions
  •   June 2025 Hydrologic Conditions
  •   May 2025 Hydrologic Conditions
  •   April 2025 Hydrologic Conditions
  •   March 2025 Hydrologic Conditions
  •   February 2025 Hydrologic Conditions
  •   January 2025 Hydrologic Conditions
  •   December 2024 Hydrologic Conditions
  •   November 2024 Hydrologic Conditions
  •   October 2024 Hydrologic Conditions
  •   September 2024 Hydrologic Conditions
  •   August 2024 Hydrologic Conditions
  •   July 2024 Hydrologic Conditions
  •   June 2024 Hydrologic Conditions
  •   May 2024 Hydrologic Conditions
  •   April 2024 Hydrologic Conditions
  •   March 2024 Hydrologic Conditions
  •   February 2024 Hydrologic Conditions
  •   January 2024 Hydrologic Conditions
  •   December 2023 Hydrologic Conditions
  •   November 2023 Hydrologic Conditions
  •   October 2023 Hydrologic Conditions
  •   September 2023 Hydrologic Conditions
  •   August 2023 Hydrologic Conditions
  •   July 2023 Hydrologic Conditions
  •   June 2023 Hydrologic Conditions
  •   May 2023 Hydrologic Conditions
  •   April 2023 Hydrologic Conditions
  •   March 2023 Hydrologic Conditions
  •   February 2023 Hydrologic Conditions
  •   January 2023 Hydrologic Conditions
  •   December 2022 Hydrologic Conditions
  •   November 2022 Hydrologic Conditions
  •   October 2022 Hydrologic Conditions
  •   September 2022 Hydrologic Conditions
  •   August 2022 Hydrologic Conditions
  •   July 2022 Hydrologic Conditions
  •   June 2022 Hydrologic Conditions
  •   May 2022 Hydrologic Conditions
  •   April 2022 Hydrologic Conditions
  •   March 2022 Hydrologic Conditions
  •   February 2022 Hydrologic Conditions
  •   January 2022 Hydrologic Conditions
  •   December 2021 Hydrologic Conditions
  •   November 2021 Hydrologic Conditions
  •   October 2021 Hydrologic Conditions
  •   September 2021 Hydrologic Conditions
  •   August 2021 Hydrologic Conditions
  •   July 2021 Hydrologic Conditions
  •   June 2021 Hydrologic Conditions
  •   May 2021 Hydrologic Conditions
  •   September 2018 Hydrologic Conditions
  •   August 2018 Hydrologic Conditions
  •   July 2018 Hydrologic Conditions
  •   June 2018 Hydrologic Conditions
  •   May 2018 Hydrologic Conditions
  •   April 2018 Hydrologic Conditions
  •   March 2018 Hydrologic Conditions
  •   February 2018 Hydrologic Conditions
  •   January 2018 Hydrologic Conditions
  •   December 2017 Hydrologic Conditions
  •   November 2017 Hydrologic Conditions
  •   October 2017 Hydrologic Conditions
  •   September 2017 Hydrologic Conditions
  •   August 2017 Hydrologic Conditions
  •   July 2017 Hydrologic Conditions
  •   June 2017 Hydrologic Conditions
  •   May 2017 Hydrologic Conditions
  •   April 2017 Hydrologic Conditions
  •   March 2017 Hydrologic Conditions
  •   February 2017 Hydrologic Conditions
  •   January 2017 Hydrologic Conditions
  •   December 2016 Hydrologic Conditions
  •   November 2016 Hydrologic Conditions
  •   October 2016 Hydrologic Conditions
  •   September 2016 Hydrologic Conditions
  •   August 2016 Hydrologic Conditions
  •   July 2016 Hydrologic Conditions
  •   June 2016 Hydrologic Conditions
  •   May 2016 Hydrologic Conditions
  •   April 2016 Hydrologic Conditions
  •   March 2016 Hydrologic Conditions
  •   February 2016 Hydrologic Conditions
  •   January 2016 Hydrologic Conditions
  •   December 2015 Hydrologic Conditions
  •   November 2015 Hydrologic Conditions
  •   October 2015 Hydrologic Conditions
  •   Seasonal Streamflow Conditions
  •   Seasonal Groundwater Conditions



      KML   Table (.csv)   Table (.pdf)

    Hydrologic Conditions Mapper

    • About This Application
    • Disclaimers

    There are five selectable monthly "data views" available by selecting a blue widget at the top of the page: (1) Streamflow conditions (2) Groundwater conditions (3) Precipitation (4) Precipitation departure from normal (5) NYC Water Supply System Status. In addition, historical monthly conditions reports and seasonal condition maps are also available by by clicking the green widgets. Seasons are defined as: "Winter": (January, February, March), "Spring": (April, May, June), "Summer": (July, August, September), "Autumn": (October, November, December). Hovering over a widget shows its title.

    NOTE: Click here for a definition of percent exceedence.

    Accessing the data:
    • Click on a drainage basin, groundwater well, or a county for a popup with detailed information and links.
    • To download data, click the the download button in the legend window.
    Changing Data Display: Initial page load defaults to "Streamflow Conditions" data view
    • Toggle the data view by selecting a widget from the header bar.
    • In the legend window, use the dropdown button to change the month you want to display.

    USGS Software User Rights Notice

    Software and related material (data and (or) documentation), contained in or furnished in connection with a software distribution, are made available by the U.S. Geological Survey (USGS) to be used in the public interest and in the advancement of science, subject to the following restrictions and understandings.

    Because the software and related material are free and provided "as is," the authors, the USGS, and the United States Government have made no warranty, express or implied, as to accuracy or completeness and are not obligated to provide the user with any support, consulting, training or assistance of any kind with regard to the use, operation, and performance of this software nor to provide the user with any updates, revisions, new versions or "bug fixes".

    The user assumes all risk for any damages whatsoever resulting from loss of use, data, or profits arising in connection with the access, use, quality, or performance of this software.

    • DOI Privacy Policy
    • Legal
    • Accessibility
    • Site Map
    • Contact USGS

    • U.S. Department of the Interior
    • DOI Inspector General
    • White House
    • E-gov
    • Open Government
    • No Fear Act
    • FOIA
    • Follow
    • Twitter
    • Facebook
    • Google+
    • GitHub
    • Flickr
    • YouTube
    • Instagram