Reliable weather data is available through several major repositories:
These are the most common files, created by statistically selecting the 12 most "typical" months from a multi-year period (often 10–30 years). The Weather Files
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. Reliable weather data is available through several major