For the data download portal, we provide access to the same source of data sets that the dashboard reads from to display. This is to provide a level of quality assurance. Additionally, we provide a link to the original source of data if possible.

While we attempt to keep all data here up to date, there may be discrepencies between the original source of data and what we have here. This is especially true of the research based hydrological input/output data, for example, as that data is updated manually, once a year, and intermittently throughout the year as technical issues are discovered. We will do our best to maintain the data here and keep it fresh, and appreciate your patience.

Each data file is named in a descriptive manner, which is described below:

[Lake abbreviation] = one of "superior", "miHuron", "clair", "erie", or "ontario" unless otherwise specified.

• Download all available data in a ZIP folder
• Water Levels
  • 1860-1917 Coordinated
    • [Lake abbreviation][Start Year].csv - Monthly Series in gridded format
    • [Lake abbreviation][Start Year]"Ann".csv - Annual Series
    • [Lake abbreviation][Start Year]"HLOC".csv - Annual Summary Data (HLOC - "H"igh "L"ow "O"pen "C"lose, like stocks, but for water levels)
  • 1918-Present Coordinated, same as 1860-1917 data with the addition of:
    • [Lake abbreviation][Start Year]"Avg".txt - contains the period of record average from the start year (i.e. 1918) to present. Start year is repeated in the second comma delimited item in the file.
    • [Lake abbreviation]"Dailies".csv - contains the aggregated daily averages from US Coordinated gauges for the current month. Updated daily.
    • [Lake abbreviation]"PrelimMo".csv - contains the aggregated monthly average from US Coordinated gauges for the current month. Updated daily.
    • [Lake abbreviation]"PrelimCDaily".csv - contains the provisional daily averages for the current month derived from all 'C'oordinated gauges. Read from the current conditions PDF here. Updated daily.
    • [Lake abbreviation]"PrelimCMo".csv - contains the provisional average for the current month derived from all 'C'oordinated gauges.
  • Master Gauge Levels
    • [Lake abbreviation]"Mog".csv - Monthly Master Gauge Data
    • [Lake abbreviation]"Anng".csv - Annual Master Gauge Data
    • [Lake abbreviation]"MogHL".csv - Annual summary data for master gauges (HLOC)
  • Miscellaneous Data
    • quinnObs.csv - Michigan-Huron 1819 - 1859 Observations from Quinn and Sellinger (1990)
  • Records
    • [Lake abbreviation]"LWD" - Low Water (Chart) Datum, with year telling the dashboard where to start drawing the line.
    • [Lake abbreviation]"LT"[Max, Mean, or Min] - The per month record maxes, mins, and per month means for each lake. 12 lines long, starting with January, ending with December (Original source numbers here in meters, and here in feet).
    • Files with "AT" in their names contain the 'A'll 'T'ime record high and low for the specified lake. The beginning of the relevant period of record, typically 1918, is the second item in the file.
• Monthly Forecasts
  • "coordinated" folder contains coordinated forecasts. The word "Coordinated" follows the lake abbreviation; "3Mo", "6Mo", or "Fore" desginate archived 3, 6 month, and current 0-6 month out forecasts respectively.
  • [Lake abbreviation, no ontario]"AHPS"[3 or 6].csv - Archived 3 and 6 month out forecasts from AHPS from the beginning of the month; the first forecast to be released each month.
  • [Lake abbreviation, no ontario]"CurrAHPS".csv - The current 0-9 month forecast from AHPS, updated daily.
• Long Term/Multi-Decadal Water Level Forecasts
  • "lofgren"[Lake abbreviation of Sup, Mih, Stc, or Eri][Base, CGCM3, or GFDL20][AE for Alternative Energy or Delta as in the Delta Method]"Fore".csv - model output from Lofgren et al. as described here.
  • [Lake abbreviation, no clair][AK, HH, MKS]"Proj".csv - model output/lake level projections from, respectively, Angel and Kunkel (2010), Hayhoe et al. (2010), and MacKay and Seglenieks (2012) as described here.
• Peleoclimate Reconstructions
  • Baedke and Thompson (2000) for Lake Michigan-Huron
  • Johnston et al. (2012) for Lake Superior
  • Wiles et al. (2009) for Lake Erie
  • Quinn and Sellinger (2006) for Lake Michigan-Huron
  • More info here.
• Percent Ice Coverage Data
  • [Lake abbreviation]"IceData".csv - contains the compiled ice data from 1973 to present via the CIS and NIC. More info here.
  • "cw/[Lake abbreviation]GLIC.csv" - contains ice concentration data from 2008 - present via the Great Lakes CoastWatch statistics page here.
• Hydrological Input/Output Data (plus water temperatures, cloud cover, and wind)
  • Precipitation, evaporation, runoff, Net Basin Supplies (NBS), percent cloud cover, river flows and diversions, air and water temperatures, and wind speeds - these folders and their files follow a similar naming convention to the water levels files mentioned above, with some additional descriptors depending on the variable, namely:
    • Whether the data are for a variable measured over the 'lake', 'land', or entire 'basin' of the respective lake.
    • Whether the data are measured in 'mm' over the lake surface or cubic meters per second ('cms', for those variables dealing with water volumes)
    • For temperatures, whether the data are for the average 'max'imum, 'min'imum, or 'mean' air temperature over a particular month, and whether the temperatures are 'mod'elled (water temps).
    Additionally, in certain variables' folders there are some other folders with data from different organizations, namely:
    • NOAA CO-OPS (COOPS folder in precip) - the files here all start with 'PCP-', followed by an 'A' for Annual or 'M' for Monthly, which is then followed by a dash and a 5 character string. The first two indicate whether the data are for over lake (LK), land (LD), or basin (BS), and the last three indicate whether the data are for lake Superior (SUP), Michigan (MIC), Huron (HUR), St. Clair (STC), Erie (ERI), or Ontario (ONT), or the entire basin (BAS).
    • USACE - Detroit District - has a folder in precip and nbs (residual NBS), with a naming convention similar to the water levels files.
    • GLSEA - Great Lakes Surface Environmental Analysis Average Water Temperature Data (original data linked to here) - found in the temps folder. These data were updated for the dashboard on 2018/10/4 for the years 1995-2017 using 1024 resolution data from the Great Lakes CoastWatch page. Data previously displayed on the dashboard are available in the folder "archive_1e".
  • sourceSpreadsheets - folder contains the MS Excel Workbooks used to create the text files in the other folders. The most up to date forms of these workbooks are found here.
  • basinWideData - folder contains monthly and annual (1950-Latest Available Year) Precip, Evap, Runoff, and NBS Data covering all lakes (as in, the total sums between all lakes for the variables)
  • PME - 'P'recip 'M'inus 'E'vap - folder contains monthly and annual time series of precipitation minus evaporation for each lake, along with the sources (folder with that name inside) that contain the source precip and evap files, plus the MS Excel workbooks to calculate the series.
  • L2SWBM - Large Lake Statistical Water Balance Model monthly 95% credible interval estimates of precipitation, evaporation, runoff, Net Basin Supplies (NBS), connecting channel flows, diversions, and change in storage. Find out more about the L2SWBM, along with downloads of the model and outputs.
  UPDATE 2016/08/16: Partial update of the datasets here. These data include the NBS and their components for each Great Lake and St. Clair, PME, and channel flows and diversions, with the exception of the isolated Niagara River and NYSBC flows. The previous set of Hydro IO data for the dashboard have been archived in the folder dashboard_1e
  
  As the data from the GLERL Monthly Hydrometeorological Database (GLM-HMD, as described here) are updated, bugs are discovered, and more, you may want to look at differences between the first set (or dashboard edition) of data here and the current one. To do so on the GLD, follow these instructions:
  1. Download this file
  2. Load the GLD
  3. Once you have clicked past the introductory dialog boxes, go to (in the dashboard) File -> Load Inventory State
  4. Find the file you downloaded, select it.
  5. Wait about 10 seconds or so. You'll see the plots 'reboot'.
  You will find the 1st edition Hydro IO data sets in the data menu under Research -> Hydrologic input/output -> Your variable of interest. The 1st edition of that dataset (for the dashboard) will have the signifier "(1e)" next to it, both on the menu and in the data tip. Change the color of a data set (for easier visual comparison) by clicking on the color icon in the bottom legend for that series, selecting the fill color, and then selecting the color of your choice.
• Oscillation/Pattern Indices - [Oscillation/Pattern Abbreviation][Monthly, Annual]Data.csv. Data are not automatically updated, so for the most up to date data, please see the links provided below:
  • Abbreviation Used - Definition
  • ao - Arctic Oscillation
  • aao - Antarctic Oscillation
  • mei - Multivariate ENSO Index
  • nao - North Atlantic Oscillation
  • oni - Oceanic Niño Index
  • pdo - Pacific Decadal Oscillation
  • pna - Pacific/North American Pattern
  • pe - Polar/Eurasia Pattern
  • soi - Southern Oscillation Index
  • wp - West Pacific Pattern

Please note (2016/01/05): the data provided and linked to here are the only datasets vetted for display on the dashboard products by NOAA-GLERL and CILER.