Homeowners who've been sitting around wondering whether they should refinance their mortgages may have missed their best opportunity of the year.

The average rate on 30-year fixed-rate mortgages jumped this week to 7.19 percent, the highest level in nearly four months, Freddie Mac, the mortgage company, said Thursday. Rates also rose on 15-year mortgages and one-year adjustable-rate mortgages.The increase in the 30-year rate, from 7.09 percent, brought the average to the highest level since the week ended Nov. 13. Seven weeks ago, the rate sank to a four-year low of 6.89 percent as Asian financial turmoil encouraged investment in the United States.

However, in the past two weeks, investors have become concerned that the Asian crisis won't dampen U.S. growth as much as thought. That implies inflation pressures could worsen, which in turn reduces the chance the Federal Reserve will cut short-term interest rates.

Though economists don't expect rates to go too much higher, they said that at year-end, it may turn out that the lowest rates of the year occurred in January and February.

"I think what you'll see is rates increasing a little bit more, but not much more," said economist Keith Leg-gitt of the American Bankers Association. "There's still a possibility rates could decline but my thinking is that opportunity has passed."

He said homeowners who secured mortgages 11 months ago, when the weekly average hit 8.18 percent, still may benefit from refinancing, just not as much as they would have if they had refinanced seven weeks ago.

"It's still a good environment for refinancing . . . (and) to go out and buy a home," he said.

However, the rise in rates already seems to have taken the edge off a boomlet in mortgage refinancing. According to the Mortgage Bankers of America, re-fi-nanc-ings accounted for 51.3 percent of mortgage applications last week. That's down 3.7 percentage points from the previous week.

Fifteen-year mortgages, a popular option for refinancing, averaged 6.80 percent this week, a four-month high and up from 6.69 percent last week.

On one-year adjustable-rate mortgages, lenders were asking an average initial rate of 5.70 percent, up from 5.65 percent and the highest in nine months.

The rates do not include add-on fees known as points.