Consumer prices for the two months ending in September increased more than three times as rapidly in the Washington area as they did across the rest of the country.

The Bureau of Labor Statistics reported yesterday that area prices climbed by 1.8 percent during August and September, a rate equal to approximately 11.6 percent on an annual basis. In contrast, prices nationwide rose only .5 percent during the same two months, or slightly more than 6 percent on an annual basis.

Much of the increase in Washington reflected higher costs for home financing and apparel -- particularly clothing for women and girls, which rose a staggering 15.7 percent.

The difference between the national increase in prices and the rise in area prices continued a zigzag pattern that has persisted throughout the year. Prices in the Washington area have either lagged behind or skipped ahead of prices nationally. Over the year, however, the differences are not great.

Prices have risen 5.4 percent in the area since last September, while they increased 5 percent nationwide.

"It's trying to balance out," said Jesse Thomas, an economist for the Bureau of Labor Statistics.

The increase in Washington area housing costs mainly reflected changes in financing and maintenance rather than any escalation in the home prices.

Financing costs climbed 6.6 percent here while, nationally, they declined and helped hold down the cost of housing. Thomas said he expected that the difference in financing costs reflected a time lag rather than real major differences.

The local index for apparel rose 4.7 percent, which BLS attributed in large part to the introduction of the fall line for women and girls. While those prices rose 15.7 percent, the prices of men's and boys' apparel rose only .5 percent. "That would be an unusual spread," said one retail industry analyst who expected the figure would be adjusted.

In contrast, the national index showed the price of women's apparel rising 2.8 percent from August to September, while the price of men's apparel rose 1.5 percent.

The cost of gas and electricity rose 3.5 percent in this area over two months, compared with a national increase of only 1.2 percent from August to September.

Other costs that climbed steeply in the Washington area were medical costs, which increased 4.1 percent from July to September to a level that is 14.8 percent above last year's costs. Food prices rose only .6 pecent, with price declines for fresh fruits, fish, sugar and sweets declining.