The rise in foreclosure filings for August over July was more than double the historic increase between these two months, said Attom Data Solutions.

"There is often a seasonal monthly increase in foreclosure activity in August paralleling the seasonal slowdown in the overall real estate market, but the 14% month-over-month increase nationwide this August is more than twice the average 6% seasonal increase in August over the previous 10 years — the highest in fact since a 37% month-over-month increase in August 2007," said Attom Data Solutions Senior Vice President Daren Blomquist in a press release.

"While this seasonal increase is certainly not enough to set off alarm bells nationwide, especially given that foreclosure activity was down annually for the 23rd consecutive month in August, there is cause for concern in a few local markets where foreclosure activity has consistently been trending higher on an annual basis this year."

There were 75,115 properties with some sort of foreclosure filing (including default notices, scheduled auctions and bank repossessions) in August, compared with 66,112 in July and 95,132 in August 2016.

The five states with the most foreclosure activity were Florida with 8,237 filings, California with 7,479, New Jersey with 5,721, Illinois with 5,137 and Ohio with 4,540.

Bucking the national trend, five states saw year-over-year increases in foreclosure filings: Alaska, up 100%; Wyoming, up 79%; Louisiana, up 59%; Vermont, up 12%; and Mississippi, up 9%. The District of Columbia had a 67% year-over-year increase in foreclosures.

New Jersey had the highest rate of filings, with one in every 625 homes. It was followed by Delaware, Illinois, Maryland and Florida.

The Houston market was showing signs of trouble even before Hurricane Harvey, with nearly 5,000 homes starting the process year-to-date, up 28% over the same period in 2016, Attom said. In comparison, foreclosure starts nationwide were down 19% since the start of the year.

There was a 44% year-over-year increase in August in the number of properties with a foreclosure filing in Houston. Of the 217 metro areas analyzed by Attom, 35 had an increase in foreclosure filings compared with August 2016, including Cleveland, up 48%; Baton Rouge, La., up 52%; and New Orleans, up 20%.