Mortgage rates fell significantly yesterday, extending a reaction to the Federal Reserve's announcement and press conference from Wednesday.  The Fed was essentially much more concerned with risks to the economic outlook than investors expected them to be.  When the Fed is concerned, they tend to not be hiking rates and if things get bad enough, they may also consider buying bonds with some of the cash they have on hand from previous bond buying exploits.

All of the above was very good for rates, but it also put very big emphasis on the upcoming economic data to shed light on just how justified the Fed's concern may be.  Today's economic data ended up being so good that it wouldn't have been a surprise to see the Fed pop out from behind the curtain this afternoon and say "just kidding!"  In other words, the Fed was super worried, and the data suggested no cause for concern.

Seeing as how the Fed's concern was good for a big move lower in rates, it's no surprise that the disarming of those concerns (even if only temporarily) is good for an equal and opposite reaction.  By the end of the day, rates had completely erased yesterday's gains.  While that's unpleasant in and of itself, apart from the past 3 days, today's rates would still be the best we've seen in nearly a year.

MND's Daily Rate Survey
52 Week
30 Yr FRM4.53%4.43%+0.104.37%5.05%
15 Yr FRM4.12%4.04%+0.083.74%4.53%
FHA 30 Year Fixed4.18%4.12%+0.064.12%4.62%
Jumbo 30 Year Fixed4.35%4.28%+0.074.28%4.81%
5/1 Yr ARM4.40%4.35%+0.053.37%4.75%