  A popular derivation of the apparent temperature of the particle transverse
momentum spectra and its inconsistency are considered. An improved formula for
the apparent temperature is discussed. It is shown that recent results on
transverse mass spectra of $J/\psi$ and $\psi^{\prime}$ mesons support a
hypothesis of statistical production of charmonia at hadronization and suggest
the early thermal freeze-out of these mesons. Using the apparent temperature
formula the collective transverse velocity of the hadronizing quark gluon
plasma is extracted to be $<v_T > \approx 0.2$. Predictions for transverse mass
spectra of hidden and open charm mesons along with bottomonium at SPS and RHIC
energies are discussed.
