WASHINGTON — Rates on 30-year mortgages edged up for a third straight week, rising to the highest level since late December, Freddie Mac reported yesterday.

The giant mortgage company said its nationwide survey showed that rates on 30-year mortgages rose to 6.24 percent, up from 6.23 percent last week.

It was the third consecutive increase and left the 30-year mortgage at the highest level since it stood at 6.26 percent on Dec. 22. Rates had dropped as low as 6.10 percent in mid-January before beginning their latest increase.

Frank Nothaft, chief economist for Freddie Mac, said that the small upward movement in mortgage rates over the past three weeks was likely to be repeated over the rest of this year, leaving the 30-year mortgage up moderately from where it is currently.

"We see this trend continuing throughout 2006, with the 30-year fixed-rate mortgage ending the year at about 6.3 percent as the housing market eases back from last year's record-setting levels toward a somewhat more normal rate of activity," Nothaft said.

Other forecasters think the increase in 30-year mortgages will be slightly faster, especially if the Federal Reserve is forced to push interest rates up more aggressively to battle inflation. Many private economists are predicting the 30-year mortgage will end the year between 6.5 percent and 7 percent.

Freddie Mac reported that rates on other types of mortgages were up as well this week.

Rates on 15-year, fixed-rate mortgages, a popular choice for refinancing a home mortgage, averaged 5.83 percent this week, up from 5.81 percent last week.

One-year adjustable rate mortgages increased to 5.34 percent this week, compared with 5.33 percent last week.

Rates on five-year hybrid adjustable rate mortgages rose to 5.89 percent this week, up from 5.87 percent last week.

The mortgage rates do not include add-on fees known as points. The 30-year and 15-year mortgages both carried a nationwide average fee of 0.6 point. The one-year and five-year adjustable rate mortgages carried an average fee of 0.7 point.

A year ago, 30-year mortgages averaged 5.57 percent, 15-year mortgages stood at 5.10 percent, one-year adjustable-rate mortgages were at 4.11 percent and five-year hybrid adjustable rate mortgages averaged 4.99 percent.