As a result, the dollar index is languishing near a five-week low, and stock markets globally are getting a tailwind.
Beyond the near-sure-thing of a Fed cut this month, markets are hungry for clues about possible reductions next year, and that will be a key focus for Chair Jerome Powell's post-meeting press conference.
But it's not the only lead on the longer-term rates outlook, after President Donald Trump earlier this week presented White House economic adviser Kevin Hassett as a potential Fed Chair when Powell's term ends in May.
An FT report said bond investors expressed concerns to the Treasury over the possibility of Hassett as head of the central bank, predicting he would aggressively cut rates to align with Trump's preference for significantly easier policy settings.
Fed officials are in a blackout period ahead of the meeting, but markets - as always - need to be on alert for social media posts by Trump.
In Europe today, ECB chief economist Philip Lane chairs a session at a conference on fiscal policy.
The most significant data point in the region is UK home prices for November.