This is a very big weak in terms of economic data and its relationship with bond market trading levels.  In a nutshell, yields dropped sharply into a new, lower range in late March.  Gains were then erased at a medium-fast pace in April, but rates found a ceiling just before re-entering 2019's previous range.  We've had just over a week of sideways-to-slightly-stronger trading since holding that line, but we're still close enough to the ceiling to worry that it might be broken.

If there is a lineup of economic data with the power to break the ceiling in bonds, it's this week's.  That said, data usually cuts both ways.  If it happened to be much weaker than expected, that could help us break below nearby technical levels.  In terms of 10yr yields, the most notable would be 2.47% on the positive side, with 2.55% and 2.62% being defensive ceilings overhead.

There are economic reports every day this week, but the most significant on Wednesday and Friday (ISM PMI indices on either day and NFP on Friday).  Wednesday gets another boost in importance from the 2pm Fed announcement.  This one stands the chance to be highly informative given the relatively surprising announcement that came out on March 20th. 

The data has been generally stronger since then and EU/China econ data has been stable or improving.    The Fed would be within its rights to say it's less concerned than it was in March.  The other option would be for the Fed to simply clam-up and make minimal changes to official announcement.  In that case, the post-meeting press conference would become doubly important.