Negative values of relative humidity in CFSR I recently started using the Climate Forecast System Reanalysis (CFSR) 6-hourly products (http://rda.ucar.edu/datasets/ds093.0/), and I noticed many values of relative humidity are negative. Is this an error in the dataset? If not, how should I interpret negative values?
I am also getting negative relative humidity from the GFS (Global Forecast System): 36-hour predicted atmosphere dataset (Provider: NOAA/NCEP/EMC, their website: http://www.emc.ncep.noaa.gov/index.php?branch=GFS)

I found this link that answers as to why relative humidity is possible in their dataset: 

http://ftp.cpc.ncep.noaa.gov/wd51we/reanal/random_notes/negative.h2o

This might apply to the one you have access too. 

Let me know if this helps.