The Southern California housing market turned in a mixed month in January, as home-foreclosure and sales numbers signaled continued turbulence but some improvement. There were 8,491 foreclosures in the six-county region, down about 18 percent from the same month last year, according to a reported released Thursday by RealtyTrac, an Irvine real estate data firm. But on a month-to-month basis, the foreclosure rate rose about 7 percent since December. In Los Angeles County, one of every 1,005 homes was in foreclosure during January, “The monthly increase in January foreclosure activity was somewhat expected after a holiday lull,” said Daren Blomquist, vice president at RealtyTrac. “ The six-county region includes Ventura and San Bernardino counties and all areas south. In the greater Valley, Palmdale was the worst performing city, with foreclosures in one of every 302 homes. Its neighbor Lancaster continued to perform poorly as well, with foreclosures in one of every 383 homes. Other Valley communities with high foreclosure rates include West Hills, with one of every 432 homes; North Hills, with one of every 539 homes; and Sylmar, with one of every 541 homes. Among Valley communities with few foreclosures were La Canada-Flintridge, with one of every 3,626 homes; Sherman Oaks, with one of every 1,737; and Thousand Oaks, with one of every 1,636. A separate report by San Diego-based real estate data firm DataQuick found that home sales in Southern California are down even as prices rise – an apparent reflection of a continuing lack of supply. The report said 14,471 homes were sold in January, down about 10 percent from a year earlier and more than 20 percent lower than December. In L.A. County, median home prices continue to rise, jumping 20 percent in the last year to $410,000. Sales dropped 7 percent to 4,913 units.