Tom White mentioned about a sample weather data set in his Book(Hadoop: the definitive guide).
http://hadoopbook.com/code.html
Data is available for more than 100 years.
I used wget
in linux to pull the data. For the year 2007 itself the data size is 27 GB.
It is hosted as an FTP
link. So, you can download with any FTP utility.
ftp://ftp.ncdc.noaa.gov/pub/data/noaa/
For complete details please check my blog:
http://myjourneythroughhadoop.blogspot.in/2013/07/how-to-download-weather-data-for-your.html