The Weather Files -

Reliable weather data is available through several major repositories:

A widely cited repository for updated TMYx files and climate change data. The Weather Files

Tools like the WeatherShift™ tool use climate model projections to adjust historical files for future decades (e.g., 2050 or 2080). Reliable weather data is available through several major

Many countries provide localized data, such as the Building Performance site for Aotearoa New Zealand. An In-Depth Look at Weather Files - ClimateData.ca The Weather Files

Direct and diffuse solar intensity, critical for calculating heat gain.

A primary source for thousands of international weather locations.

The .epw (EnergyPlus Weather) format is a global standard developed by the U.S. Department of Energy . Other common versions include TMY3 and IWEC files.