Rising mortgage rates hit home sales and prices hard in expensive Northeast cities in the first three months of 1989, but booming West Coast markets weathered the storm, a real estate trade group said today.

California accounted for the top five appreciation rates in the nation. Home prices in Orange County shot up 30.2% to a median of $237,900. In Los Angeles, prices rose 26.3% to $201,000; San Diego, 21.9% to $163,900, and Riverside-San Bernardino, 21.6% to $116,000.

New York area prices-the fifth highest in the nation after San Francisco, Orange County, Honolulu and Los Angeles-sank 2.8% to $181,700. Boston, New Haven and Hartford-the sixth, seventh and eighth most pricey cities-posted appreciation rates of 0.9%, minus 1.3% and minus 0.5%, respectively.