Understanding EPW meteorological flag codes

asked 2020-03-03 09:27:04 -0500

dhollman gravatar image

updated 2020-03-08 12:55:44 -0500

The EPW specifications state that the meteorological fields will have one of a specific set of data source & uncertainty flag codes.

(I'm referring to page 52 of this document: https://energyplus.net/sites/default/...)

The data source flag codes are supposed to be: A-F, and ?

The uncertainty flag codes are supposed to be: 0, and 7-9 (values 1-6 not used)

However I'm seeing values that are not in these ranges in some sample files.

Example: TMY3 data for Syracuse, NY (https://bcl.nrel.gov/node/79057)

For the first hour's data the codes are:


It is the last 12 codes which seem to have some inconsistencies with the specifications. Neither an underscore character nor an asterisk seems to be valid...

What does this mean? Am I looking at out of date specifications?


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