Washington area consumer prices rose 0.9 percent during December and January, with housing and food accounting for most of the increase.

Prices rose during those two months at an annual rate of 5.6 percent, according to the Labor Department's Bureau of Labor Statistics. The rate was high compared to a 3.9 percent rate for the nation during the same two months but low in comparison to the inflation that has been characteristic of the area in recent years and in comparison to the two-month increase of 1.4 percent for October and November.

Approximately 80 percent of the increase reflected the higher food and housing costs. Food and beverage costs rose 1.6 percent, with most of the increase caused by higher vegetable prices. Freezing weather and an insect infestation in lettuce fields in California affected those prices.

Other factors in the food price increase were higher prices for fish, pork, cola drinks, coffee, restaurant meals and alcoholic beverages.

The rise in housing costs reflected higher prices for out-of-town lodging, natural gas, electricity and furniture--increases that were only partially offset by a decline in mortgage interest costs.

Transportation costs rose as a result of higher charges for most types of public transportation, including air fares, even though gasoline prices declined. Automobile financing charges and the costs of used cars also went down.

Other prices that went up included the costs of medical care, which rose 1.7 percent, and entertainment.

Lower prices were registered for most clothing items, according to the BLS. In December, when retailers make most of their money for the entire year, sales were flat. Figures are not available yet for January sales, but severe weather kept shoppers away during part of the month.

Prices in the metropolitan Baltimore area rose 0.5 percent in December and January. There, higher prices for housing, transportation, food and medical care were all factors. The cost of clothing and entertainment fell in the two-month period.