NLR Flatirons Campus (M4)
Daily Plots and Raw Data Files
December 30, 2025 to September 14, 2026
Notice: Any publication based in whole or in part on these data sets should conspicuously acknowledge the data source as the National Laboratory of the Rockies using the citation and DOI listed on the bottom of the Flatirons M4 homepage.
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Notice: Data have not been reviewed for accuracy or completeness. Please read the disclaimer.
To determine instrument measurement uncertainty, please download the Excel® uncertainty spreadsheet to compute these values. (5.5 MB XLSX)
Further instrument information, including current serial numbers and calibration factors, are available by clicking the instrument name. Some of these serial numbers can also be clicked for further instrument calibration history and uncertainties.
Irradiance data will always appear on primary axis and meteorological data will always appear on secondary axis.
The selection of an end date only applies to selected or all raw data. Plots and wind roses can only be generated one day at a time using the start date.
Selected data or all raw data has the option of being compressed using the ZIP format. An extraction utility can be obtained from PKWare or WinZip
Selected hourly data will generate hourly data by averaging the input data for the entire day(s), custom data will be ignored. Note: DO NOT use this feature with wind direction measurements, the resulting averages will be bogus.
Selected daily statistics will generate daily totals (for irradiance data) and daily averages (for meteorological data) using the input data for the entire day(s), custom data will be ignored. The daily maximum and minimum (if applicable) will also be generated. Note: Negative values from shortwave irradiance instruments will be set to zero when accumulating daily totals. DO NOT use this feature with wind direction measurements, the resulting averages will be bogus.
The raw data options are the complete raw data record(s) from the datalogger, these are the raw data field IDs.
English conversion only applies to selected data or plot and has no effect on irradiance or custom data.
When selecting raw data or wind rose, all selections (except the date) will be ignored.
The wind rose is generated using average wind speed and direction for the selected level.
The calculate third component option uses the formula: Global = Direct * Cosine(Zenith) + Diffuse to calculate a third component based on the selected two. This option should only be used for pyrheliometers and horizontal pyranometers.
For automated data extraction, please use the MIDC API.