As AQ pointed out this AM, in the midst of low volume and little, if anything to drive the markets, any given trading has the potential to move prices more than it otherwise would on a normal volume day.  The evidence of this chopatility is readily apparent looking at today's trading in and of itself.

That blue line is the S&P by the way, and yes, it is currently trading over it's long term resistance at 1110.00.  Whether or not it will mean much to the markets if it closes over resistance today remains to be seen.  But likely, unless volume picks up, the outlook on stocks, like bonds, can be slightly dismissive ahead of the FOMC meeting and announcement.

A bit wider of a view lends some perspective to the shape of today's volatility.  Choppy today?  Yes...  Out of line with recent trends and ranges?  No.

Be aware, as always, that some lenders reprice for the worse when MBS are at their lows regardless of any mitigating context from low volume or lack of data.  So with the 4.5 down 2 ticks on the day at 101-06, it's not out of the realm of possibility for the odd reprice.  And the closer prices move to 101-00, the more likely that becomes. 

But notice the strong showing of support at 100-30 in the 2 day chart.  It wouldn't be until prices approached or broke those levels that widespread and more substantial reprices would become a risk.  This isn't necessarily a comfortable environment to keep floating deals floating, I know.  But if anything changes about the bigger picture on the week, we'll let you know ASAP.