A recent LEED MV plan review comment asked "please indicate the proposed calibration method to account for the local weather conditions during the performance period."

This raises the question for me - are model results significantly impacted by the difference between historic weather data and performance-period data?

When I'm engaged in Measurement and Verification, I can install a weather station that records data for performance period to allow for calibration. (http://www.gsd.harvard.edu/research/gsdsquare/Publications/BuildingSimulation2009.GundHallModel.pdf)

But for an investment-grade energy audit with historic bills, I'm not sure where to turn for all the variables needed to construct a weather file.

Anyone on this list have a recommendation?

(I'm specifically looking for NYC, 2009, weather data for an eQUEST model.)

Aaron Dahlstrom , PE, LEED(r) AP