This is more of a "heads-up" alert as there haven't been any major changes in prices in the past few hours.  Instead, Treasury yields have trickled gently to the highest levels of the day with the 10yr up 2.4bps at 4.587.  MBS are been at their lowest levels of the day for about 30 minutes, and just far enough from AM rate sheet print times for some lenders to consider negative reprices.  

The best way to use this alert is as a cue to lock if you were already planning on locking today.  If you were not, again, there's nothing new and threatening happening right now--just a slow trickle of additional weakness.