Two economists for major California financial institutions are predicting only slight downturns in that state's economy and both believe the housing industry in the West should be the least affected.

This optimistic forecast -- a sharp contrast to the predictions of a major downturn or even a recession that were made a few months ago -- came from Jerry E. Pohlman and Joseph A. Wahed at the two-day national mortgage banking conference sponsored by the Mortgage Bankers Association of America last week at the Bonaventure Hotel in Los Angeles.

Pohlman, chief economist for California Federal Savings and Loan Association, the nation's largest federal S&L, said that housing starts nationally will total 1.67 million units this year, down 17 percent from last year's 2.01 million starts. But the West -- including California -- will decline only 14 percent, compared to a 22 percent drop in the North Central states.

Wahed, vice president and manager of the economics department of Wells Fargo Bank, said that California will be relatively better off than the rest of the nation thanks to solid growth in the state's three key industries: agriculture, aerospace and tourism.

Mortgage interest rates for conventional loans with 20 percent down payments will go from 10 1/2 percent now to 11 percent "and perhaps a bit higher" by the second half of this year, Pohlman said. He predicted that short-term interest rates -- including the prime rate -- will be in the 12 percent range by mid-year.

Wahed said that the signs of strength in the nation's economy are widespread with retail sales and automobile sales surprisingly strong, business investment in new plant and machinery picking up, housing activity strong despite high interest rates and a general feeling of confidence despite generally had news here and abroad.

Both economists agreed that the rate of price appreciation of houses in California will be about 8 to 10 percent, about the same as the inflation rate, but down sharply from last year's 15 percent and the 20 percent and higher annual rates of the 1976-77 period.