Foreclosures in the Sun Belt remained high, while filings related to rising unemployment rates may be growing, according to a midyear foreclosure rate report by online foreclosure marketplace RealtyTrac.

“Foreclosure activity continued its upward trajectory nationwide and in the majority of metro areas in the first half of the year, but there are some significant differences beginning to show up in the data,” said James J. Saccacio, chief executive officer of RealtyTrac, in a release from the company.

Saccacio went onto say that cities such as Provo, Utah, and Boise, Idaho, which have maintained lower foreclosure rates up to now, saw foreclosure rates jump in the past six months, an indication that increasing unemployment rates are beginning to impact foreclosures.

The report denoted that foreclosure rates in the sun belt remained among the highest in the nation. The company said 35 of the 50 highest metropolitan foreclosure rates were in cities in California, Florida, Nevada and Arizona.

According to the report, Las Vegas has the country’s highest foreclosure rate for cities with a population of more than 200,000; the city saw 7.45% of its housing units, or one in every 13 homes foreclosed upon in the first six months of 2009. That’s a 22% increase from the previous 6 month period, according to RealtyTrac.

The Cape Coral-Fort Myers metro area in Florida had the second-highest foreclosure rate, with 7.2% of its homes foreclosed upon in the first half of this year.

Some cities saw foreclosure rates decline during the first six months of 2009, including Stockton, Calif., which saw its rate fall nearly 4% from the previous six-month period. Detroit’s foreclosure rate also fell 8% when compared to the rate during the last six months of 2008. Foreclosures in Cleveland also declined by 11%, compared to the previous 6 months, according to the report.