Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
Horizontal Infrared Radiation is equivalent to 'surface thermal radiation' value available for all NWP models. If you need to look this up quickly, feel free to check out http://weatherdownloader.oikolab.com/ (disclaimer - I run this tool), based on ERA5 data from ECMWF. This should fit well under the free tier and you can download up to 6 months of data without signing up.
The parameters are named 'surface_thermal_radiation' and 'total_cloud_cover' (for the opaque sky cover).
