Mortgage rates tumbled to their lowest levels since late May.

The average 30-year fixed rate fell 11 basis points, to 5.59 percent. A basis point is one-hundredth of a percentage point.

This week's average 15-year fixed rate -- a popular option for refinancing -- plunged 14 basis points, to 4.93 percent.

The average jumbo, 30-year fixed slid 5 basis points, to 6.86 percent.

Adjustable-rate mortgages were split. The one-year adjustable-rate mortgage edged up 1 basis point, to 5.18 percent. The popular 5/1 ARM sank 12 basis points, to 5.05 percent.

Mortgage application activity rose a seasonally adjusted 10.9 percent when compared to a week earlier, according to the Mortgage Bankers Association.

For the week ending July 3, applications for new purchase increased 6.7 percent. Refinancing activity jumped 15.2 percent. The numbers included an adjustment for the Fourth of July holiday, according to the MBA.

To find and compare mortgage rates in your area, visit Bankrate's interactive search tool.

-- Chris Kissell