The short-term length-of-day chart is very noisy, and has some seasonal components as well. The IERS Bulletin A has a table of DUT1 values for the next year, pl

The short-term length-of-day chart is very noisy, and has some seasonal components as well. The IERS Bulletin A has a table of DUT1 values for the next year, plus a formula for longer-term projections. (LoD is the rate of change of DUT1.) If you ignore the seasonal components, it is a simple linear formula, multiplying the Julian day number by a LoD factor. Last time I looked this longer-term LoD factor was 320μs short of 24 hours, which suggests the next leap second will be in about 5 years time (2027) and will be a negative leap second. There was a short period towards the start of this year when it looked like the LoD was increasing, but that was only temporary. The decrease in LoD has been fairly consistent (apart from the occasional pause like earlier this year) for a few years, starting when the LoD was more like 1ms slower than 24h, so it was a while before the wider time-keeping community realised something weird is happening. I am collecting various links and notes and bits of code on this and related topics at https://dotat.at/writing/time.html https://dotat.at/writing/time.html