For the weather variable, all of the suboptions that I have tried (i.e. temperature, wind speed) work except current conditions. This is my code:
${weather http://weather.noaa.gov/pub/data/observations/metar/stations/ KSZT weather}
Replacing weather with cloud_cover does not fix it.
Occasionally, after restarting conky it will work for a while but this isn't a consistent fix and it doesn't work 99% of the time. There is no error message or relevant output from conky, it just doesn't show the current conditions.
This is certainly a low priority bug. But it is frustrating that it occasionally works- which makes me think it is fixable.
Oh, I had better give version info:
Conky 1.9.0 compiled Thu May 24 15:31:18 UTC 2012 for Linux 2.6.24-31-server (x86_64)