Looking at the spectrograms and glitchgrams on the summary pages for January 2nd there seems to be some interesting behaviour from about 10 - 35 Hz at LHO. The noise drops in this band over the course of the day and glitches in this band become less frequent as well. It does not seem to correlate to wind speed or ground motion, at least not in an obvious way. Looking at the ground motion BLRMS page of the summary pages, there do seem to be some spikes between 4 - 6 UTC, in multiple bands. However these spikes are relatively short-lived and the noise in the spectrograms starts before that. I've attached a few images showing noise and glitches from the band of interest.. The plots are also visible on the summary pages.
The last lock loss on 1 Jan was due to PSL issues (see alog). The low frequency noise reported here seems to be correlated with unusual noise in PSL ISS and also shows up in IMC frequency noise. The attached pdf shows apparently normal behavior on 1 Jan for PSL ISS, IMC frequency noise, and strain followed by excess noise in all three on 2 Jan. While things appear to have calmed down on 3 Jan (so far), there appears to be a PSL glitch that shows up in the strain channel.
