To anyone with a pedigree in mortgage banking, the headline to this story should make little sense -- mortgage rates, after all, tend to do better as economic distress heightens. Investors typically flock to Treasuries, pushing yields (and by extension, mortgages rates) downward. But these are not exactly normal times, and the spread between Treasuries and mortgages has been anything but what would usually be expected. As a result, mortgage rates soared this week, according to data released Thursday by Freddie Mac (FRE). The company's weekly rate survey found that a 30-year fixed-rate mortgage averaged 6.09 percent with an average 0.7 point for the week ending Sept. 25, up sharply from last week when it averaged 5.78 percent. Last year at this time, the 30-year FRM averaged 6.42 percent -- so, despite the jump, rates remain low in historical terms. Adjustable rate mortgages soared, as well. Five-year Treasury-indexed hybrid ARMs averaged 6.02 percent this week, with an average 0.6 point, up 35 basis points from last week; while one-year Treasury-indexed ARMs average 5.16 percent, up 13 basis points. "Mortgage rates followed Treasury bond yields higher this week amid market uncertainty over the current state of the economy," said Frank Nothaft, Freddie Mac vice president and chief economist. "Compared with last Thursday, 10-year Treasury yields are up about 0.3 percentage points, and 30-year fixed-rate loans moved up about the same amount. The largest jump in rates came on Friday, Bankrate.com's Holden Lewis reported Thursday; that was one day after a near-panic seized up credit markets and details of a Treasury bailout first emerged. While rates continued to rise Monday, according to Lewis, they have pretty much leveled off since that time. Disclosure: The author held no relevant positions when this story was published. Indirect holdings may exist via mutual fund investments. HW reporters and writers follow a strict disclosure policy, the first in the mortgage trade.