We use Singular Spectrum Analysis (SSA) for precision estimation of time series of total zenith atmospheric delay for a list of European GNSS data stations proceed in Main Astronomical Observatory GNSS processing centre. The series are downloadable at ftp://ftp.mao.kiev.ua/pub/gnss/products/IGS05/. Analysis of the principal components of the series allowed us to clean the series by removing noise out of them. With the capabilities of SSA some gaps in the data were filled out.