Hello,
NREL provides access to data measured at the National Wind Technology center since 1996 on the website below. You can use the website to download average hourly data for single years.
For a description of the SAM's SRW file format, please see the "Weather File Formats" topic in SAM's Help system (under Weather Data in the table of contents). You can also use one of the SRW files in the wind resource library that comes with SAM as a model for developing your own files.
www.nrel.gov/midc/nwtc_m2/
Best regards,
Paul.