Foreclosure filings fell in 24 of the nation's 42 largest counties from October to November, according to new data from research firm DataQuick

The California-based company released its housing performance report for November, showing marked improvements in home prices, sales and lower foreclosure filings.

Still, the research firm said the fiscal cliff, which could come with mandatory tax increases, is a threat to the housing market, along with the nation's shadow inventory. The report also noted that negative equity tied to existing homeowners is still a threat to future housing activity.

Home price growth was positive in 41 of the 42 largest counties when comparing November to the previous month, DataQuick said.

Sales also increased in 13 of the 42 surveyed counties last month.

When looking at foreclosure activity from the second to third quarter, DataQuick says foreclosures fell in 20 of the 42 reported counties over the previous period.

"While there is evidence that a recovery in housing is underway nationally, the strength of the housing market varies across the country," said Gordon Crawford, vice president of analytics for DataQuick. "In comparison to prior reports, we see that home price growth and foreclosure performance improved, while sales performance worsened."