MBS Day Ahead: Short Week Begins With Bonds Testing Boundaries

After being closed for Labor Day yesterday, the bond market is noticeably weaker to start the new week.  In the overnight session alone, yields rose enough to being 10yr yields up to an important technical ceiling at 1.375.  This matches the intraday high from 2 weeks ago and is just under the 1.379 high from 4 weeks ago. 

Incidentally all 3 visits to this ceiling have occurred on Treasury auction days.  To whatever extent “supply” concerns are behind the weakness, extra pressure is being added this morning from corporate bond issuance.  If bonds follow their…