The MAX6577 temperature sensor appears to exhibit both Gaussian and burst noise.  The Gaussian noise is desirable since it improves the temperature measurement precision with appropriate filtering, but the burst noise is slightly problematic.  The burst noise produces abrupt 10 mC to 20 mC steps in the temperature measurement which result in 2 ppb to 5 ppb perturbations of the frequency correction.  These perturbations produce bursts of minor offset drift.

These sudden shifts need to be mitigated to reduce tracking error in NTP and PTP clients.