WASHINGTON – Unemployment rates galloped higher in most U.S. metropolitan areas in July when compared to a year earlier, with 11 areas recording jobless rates of 10 percent or more, the Labor Department reported on Wednesday.

All told, 338 of the 369 areas in the survey said their unemployment rates had increased from July 2007, and the number reporting jobless rates of at least 7 percent more than doubled to 90 from 29, the Labor Department said.

In July, the national unemployment rate was 5.7 percent, seasonally adjusted. The Labor department said without the smoothing out for seasonal factors, it was 6.0 percent in July compared to 4.9 percent a year earlier.

None of the metropolitan data reported by the Labor Department is seasonally adjusted.

El Centro, California, had the highest unemployment rate of 23.3 percent, followed by Yuma, Arizona, at 20 percent.

The lowest rates were found in South Dakota's Sioux Falls, at 2.4 percent, and Rapid City, at 2.5 percent. Idaho's Idaho Falls also had an unemployment rate of 2.5 percent.

In terms of the number of jobs, 188 metropolitan areas reported increases from July 2007, while 110 reported decreases and 12 had no change.

Texas had the largest gains, with the job market in the Dallas area swelling by 68,000 positions and in Houston by 57,100.

The largest year-over-year drops in employment were centered in California's Los Angeles area, which lost 45,000 jobs, and Riverside area, which shed 26,000 positions.

(Reporting by Lisa Lambert; Editing by Tom Hals)