Washington area consumer prices declined by one-tenth of one percent from September to November, the second time in 12 months that prices have dropped, the Bureau of Labor Statistics reported yesterday.

While prices were declining here, they rose approximately 0.6 percent nationally over the same two-month period, BLS figures showed.

The bureau calculates the local CPI every two months, but national reports are issued monthly.

A dip in housing costs was a major factor in the decline of prices in the Washington area, as it was nationally. Food and beverage prices also dropped locally by 0.9 percent; much of the decrease was due to lower prices for fresh fruit, beef and fresh milk.

The contrast between local and national prices continued a year-long pattern in which prices in the D.C. area have either lagged behind or skipped ahead of prices nationally. Two months ago, for instance, the consumer price index in the D.C. area increased more than three times as rapidly as the national index.

Over the year, the differences have been less pronounced, but price increases in the Washington area have been slightly less. For the 12 months ended November 1982, prices rose by 4.6 percent nationally and 3.9 percent locally, Bureau of Labor Statistics economist Jesse Thomas said.

The other drop in consumer prices during the past 12 months was from March to May, when Washington area prices fell two-tenths of one percent.

During the two months just ended, housing costs in the Washington area declined by 0.4 percent. Lower mortgage costs and lower prices for electricity and furniture offset price increases for housing purchases, natural gas and rentals.

Apparel and upkeep costs, medical costs and the cost of many types of entertainment rose. College tuition and the prices of school books, toys, hobbies and cigarettes also went up here during the two-month period.