NEW YORK (AP) — While no one is ready to call the bottom of the worst housing collapse in decades, there were glimmers this week that the severity is waning.

The decline in home prices is starting to ease and in some cities values are starting to rise again. Existing home sales rose slightly from June to July, and the glut of newly built homes on the market fell to a five-month low last month.

"The bottom of the housing downturn is coming into view," said Moody's Economy.com chief economist Mark Zandi.

But there are still very serious risks to any housing turnaround. Mortgage rates are above 6 percent when they should be below, based on historical trends. Fannie Mae and Freddie Mac, which together hold or guarantee half the U.S. mortgage debt, could need a government bailout. And a slowing economy and rising unemployment could scare off homebuyers.